Term
| What is the most diverse plant division |
|
Definition
|
|
Term
| Alternation of Generations |
|
Definition
| A sequence in a life cycle in which a haploid, gamete-producing phase is followed by a diploid, spore-producing phrase; the spores of the latter reinitiate the haploid phase |
|
|
Term
| Describe the gametophyte phase in plance |
|
Definition
| (haploid) -Microscopic in flowering plants -Produce gametes by mitosis |
|
|
Term
| Describe the sporophyte phase in plants |
|
Definition
| (diploid)-In flowering plants, large, independent, recognizable “plant” -Produces spores by meiosis |
|
|
Term
|
Definition
| plants that die after producing seeds during their first year of life |
|
|
Term
|
Definition
| plants that do not reproduce the first year but may the following year |
|
|
Term
|
Definition
| plants that live for more than 2 years, often producing seed every year after maturity |
|
|
Term
| What are the four essential processes of plant growth and development |
|
Definition
| Cell division, growth, cell specialization, and apoptosis |
|
|
Term
| What is the shoot apical merristem |
|
Definition
Rapidly dividing cells at shoot tips and branchs -Produces shoot system
(Stems, branches, leaves and other organ systems) |
|
|
Term
| What is the root apical merristem |
|
Definition
Rapidly dividing cells at root tips
-Produces root system (Roots and root branches) |
|
|
Term
| What do SAM and RAM lay down and what do these produce |
|
Definition
| SAM and RAM lay down additional meristematic tissues (primary meristems) that produce specialized primary tissues |
|
|
Term
| What are the three types of primary merristem |
|
Definition
| Protoderm, Procambium, and Ground meristem |
|
|
Term
| What does the protoderm generate |
|
Definition
|
|
Term
| What does the procambium produce |
|
Definition
| It produces vascular tissues (primary xylem and phloem) |
|
|
Term
| What does the ground meristem produce |
|
Definition
| it produces ground tissues, (cortex, pith) |
|
|
Term
| What does the secondary meristemm do |
|
Definition
| the secondary meristem (or lateral meristems) surround the established stem of a plant and cause it to grow laterally (i.e. larger in girth/diameter) |
|
|
Term
| What are the two types of secondary meristem |
|
Definition
| Vascular cambium and Cork cambium |
|
|
Term
| What is the purpose of the stem cells contained in the plant meristems |
|
Definition
| Plant meristems contain stem cells that remain undifferentiated but can produce new cells capable of differentiating into specialized tissues. Plant stem cell divides to produce one cell that remains unspecialized and another cell that is capable of differentiating into various types of specialized cells |
|
|
Term
| What are two things that growth in plants involves |
|
Definition
| producing new cells and cell expansion |
|
|
Term
| When does cell expansion occur and what does it allow for |
|
Definition
| Expansion occurs when water enters the central vacuole by osmosis. It allows for rapid plant growth |
|
|
Term
| What purpose do leaves play in plants |
|
Definition
| They are the main photosynthetic systems and the site of gas exchange (thus they are susceptable to water loss, and drying). |
|
|
Term
|
Definition
| only one blade, advantageous in shade by providing maximal light absorption |
|
|
Term
| Describe complex or compound leaves |
|
Definition
| dissected into leaflets, common in hot environments for heat dissipation |
|
|
Term
| What kind of venation do eudicot leaves have |
|
Definition
| pinnate or palmate venation |
|
|
Term
| Describe pinnate or palmate venation |
|
Definition
| Netted veins w/ branching patterns provide more support to the leaf |
|
|
Term
| What type of venation do monocot leaves have |
|
Definition
|
|
Term
| What are some leaf surface and their purposes |
|
Definition
Waxy cuticle on epidermis helps avoid desiccation and filter UV radiation, reduce microbe and animal attack
Guard cells regulate stomatal opening and closing. Trichomes offer protection from excessive light, ultraviolet radiation, extreme air temperature, or attack by herbivores |
|
|
Term
| What are some functions of the stem in plants |
|
Definition
They provide support for the plant body
They carry nutrients throughout plant (in vascular tissues). They serve as a defense system to protect against predators and infection. They produce leaves, branches, and flowers. They hold leaves up. They may function in storage and photosynthesis. |
|
|
Term
| What purpose do nodes serve in stems |
|
Definition
| They are attachment for leaves and branches |
|
|
Term
| What purpose do buds serve in stems |
|
Definition
| They contain meristematic tissue, areas of growth (stems, leaves flowers). |
|
|
Term
| What is primary vascular tissue derived from |
|
Definition
| Its derived from primary meristem (procambium) |
|
|
Term
| What is secondary vascular tissue derived from |
|
Definition
| Its derived from secondary meristem (vascular cambium) |
|
|
Term
| What is the purpose of the xylem in plants and where is it located |
|
Definition
| The xylem is primarily responsible for the transport of water and dissolved minerals from roots upward in plant body. It is in vascular bundles, located towards the center of the stem |
|
|
Term
| What is the purpose of the phloem in plants |
|
Definition
| The phloem is primarily responsible for the transport of organic nutrients (dissolved sugars) from leaves or roots to other areas of the plant (flow can occur in both directions, depending on time of year) |
|
|
Term
| How are vascular bundles arranged in monocots |
|
Definition
| They are scattered throughout |
|
|
Term
| How are vascular bundles arranged in dicots |
|
Definition
| They are arranged as a cylinder with pith – parenchyma cells inside the ring |
|
|
Term
| What is primary xylem composed of |
|
Definition
| Unspecialized parenchyma cells, stiff fibers for structural support (sclerenchyma cells), and tracheids and vessel elements (dead cells) conduct water and dissolved minerals |
|
|
Term
| What is primary phloem composed of |
|
Definition
| Sieve elements (living cells), companion cells (also living) aid seive element function, and parenchyma cells |
|
|
Term
|
Definition
Rhizomes- underground stems
Stolons- aboveground creeping stem
Tubers (potatoes) and bulbs (onions, irises, tulips) are underground modified stems that store food |
|
|
Term
| In the zone of elongation how are the cells extended |
|
Definition
| The cells are extend by water uptake |
|
|
Term
| What happens in the zone of maturation |
|
Definition
| There is root cell differentiation and tissue specialization. This zone is identified by presence of root hairs (water and mineral uptake) absent from older regions. |
|
|
Term
| What kind of roots do eudicots often have |
|
Definition
| they often have taproots(one main root with many branches) |
|
|
Term
| What kind of roots do monocots often have |
|
Definition
| fibrous roots (no main root, many equivalent branches from base of stem) |
|
|
Term
|
Definition
| originate from stem, support the plant |
|
|
Term
|
Definition
| broad supporting structures in shallowly rooted trees |
|
|
Term
|
Definition
| upward directed appendage, allows for gas exchange |
|
|
Term
| Give examples of some fleshy storage roots |
|
Definition
|
|
Term
| Define electrical signals as they relate to plants |
|
Definition
| they are action potentials particularly important in rapid plant movements |
|
|
Term
| Define chemical signals as they relate to plants |
|
Definition
| chemical hormones control plant cell, tissue and organ development and allow plants to respond to environmental stimuli |
|
|
Term
| Give some examples of external environmental stimuli |
|
Definition
-Light, atmospheric gases (CO2 and water vapor), temperature, touch, wind, gravity, water, rocks, and soil stimuli
-Herbivores, pathogens, organic chemicals from neighboring plants, and beneficial or harmful soil organisms
–Agricultural chemicals including hormones |
|
|
Term
| Define plant signal transduction |
|
Definition
| Process in which a cell perceives a signal, switching on an intercellular pathway that leads to cellular response |
|
|
Term
| Signal Transduction involves |
|
Definition
| Receptors or sensors, messengers or second messengers, and effectors |
|
|
Term
| Define auxins and their importance to plants |
|
Definition
| the “Master” plant hormone; It influences plant structure, development, and behavior in many ways like:– Apical-basal polarity of plant body - Important in the development of vascular tissues - Alter pattern of growth and development in response to environment |
|
|
Term
|
Definition
| Auxin is produced primarily in apical shoot tips and young leaves. Its directionally transported. May enter cells by diffusion. AUX1 plasma membrane protein (auxin influx carrier) at apical cell end. PIN proteins transport auxin out (auxin efflux carriers) at basal or lateral surfaces of cells. Polar transport – auxin flows down in shoots and into roots. Differences in localization of carriers explains variation in auxin concentration within plants |
|
|
Term
| What did some of the first experiments of phototropism reveal |
|
Definition
| shoots of seedlings left uncovered grew toward the light |
|
|
Term
| What did experiments performed by Went and Briggs reveal |
|
Definition
| They revealed the Role of Auxin in Phototropism |
|
|
Term
| What are some effects of auxin in plants |
|
Definition
Seedless fruit production (Stimulates flower ovaries to mature into fruits),
Retardation of premature fruit drop,
Used as commercial rooting compound, Pinching topmost shoots alters new outgrowth, produces bushy plants |
|
|
Term
| What are some other important plant hormones besides auxin |
|
Definition
| Cytokinins, Gibberellins, and Ethylene |
|
|
Term
|
Definition
| promote cell division in plant shoots and roots |
|
|
Term
|
Definition
| influence various developmental processes, including stem elongation, germination, dormancy, flowering and leaf and fruit maturation and senescence. |
|
|
Term
|
Definition
| stimulates or regulates the ripening of fruit, the opening of flowers, and the abscission (or shedding) of leaves |
|
|
Term
| What do stress hormones do |
|
Definition
| They help plants respond to environmental stresses such as flooding, drought, high salinity, cold, heat, and attack by microorganisms and herbivores |
|
|
Term
| List some stress hormones |
|
Definition
| Abscisic acid, Brassinosteroids, Salicylic acid (SA), Systemin, Jasmonic acid, and Nitric oxide (NO) |
|
|
Term
| What are some defenses plants have against herbivore attack |
|
Definition
They have a wide variety of chemical defenses. Plant response to jasmonic acid can cause synthesis of chemicals that are repulsive to herbivore
Chemical signals can also cause release of chemicals attract predators of their attackers and/or cause defensive response in neighboring plants. |
|
|
Term
| Give some examples of systemic acquired resistance (SAR) |
|
Definition
| Localized response can result in the production of alarm signals that travel to noninfected regions of a plant and induce widespread resistance to diverse pathogens, Jasmonic acid (May cause production of defensive enzymes or tannins (toxic to certain microorganisms)), and Volatile compounds may be transmitted to nearby plants, initiating defense response. |
|
|
Term
|
Definition
| Growth in response to the force of gravity |
|
|
Term
| What part of the plant is negatively gravatropic |
|
Definition
|
|
Term
| What part of the plant is positively gravatropic |
|
Definition
|
|
Term
|
Definition
| Statoliths are starch-heavy plastids contained in Statocytes |
|
|
Term
| What is the purpose of statoliths |
|
Definition
| Heavy statoliths sink, causing changes in calcium ion messengers, inducing lateral auxin transport. This changes direction of root or shoot growth. |
|
|
Term
|
Definition
| touch responses in plants |
|
|
Term
| What happens when roots encounter rocks as they grow down |
|
Definition
| Touch response temporarily supersedes their response to gravity. Roots grow horizontally until they get around the barrier, then downward growth in response to gravity resumes |
|
|
Term
| What are "nastic responses" or “thigmonasty" |
|
Definition
| These are more rapid responses caused by changes in water content of cells. Ex. The leaves with pulvinus to become limp when touched. Electrical impulse transmitted, causes pumping of ions, loss of plant cell turgor pressure. |
|
|
Term
| How do photoreceptors respond to light |
|
Definition
| Photoreceptors respond to light absorption by switching on signal transduction |
|
|
Term
| What are some results of photoreceptor's response to light |
|
Definition
| These responses result in sun tracking, phototropism, flowering and seed germination |
|
|
Term
| What are phytochromes involved in |
|
Definition
| They are involed in timing of germination and flowering |
|
|
Term
| What do blue-light receptors do |
|
Definition
| Cryptochromes help young seedlings determine if light environment bright enough for photosynthesis. If not, seedlings continue to elongate |
|
|
Term
| What are some classifications of plants according to how their flowering responds to night length |
|
Definition
| Flowering plants can be classified as long-day, short-day, or day-neutral. |
|
|
Term
| Define the flowering of long-day plants |
|
Definition
| flower in spring or early summer, when the night period is shorter (and thus the day length is longer) than a defined period |
|
|
Term
| Define the flowering of short-day plants |
|
Definition
| flower only when the night length is longer than a defined period such as in late summer, fall, or winter, when days are short |
|
|
Term
| Define the flowering of day-neutral plants |
|
Definition
| flower regardless of the night length, as long as day length meets the minimal requirements for plant growth |
|
|
Term
| What are photochromes and what are they effected by |
|
Definition
| Photochromes are red- and far-red-light receptors. They are effected by photoperiodism |
|
|
Term
| What are the 2 conformations that photochromes flip back and forth between. |
|
Definition
|
|
Term
| Describe the P(fr)(the active) conformation |
|
Definition
The P(fr) conformation only absorbs far-red light and activates cellular responses - Moves from cytoplasm to nucleus, impacting gene regulation
– Absorption of far red light causes conversion to P(r) (inactive) |
|
|
Term
| What happens when P(fr) is left in the dark |
|
Definition
| When left in the dark (or exposed to far red light), Pfr transforms to red light absorbing Pr (inactive) |
|
|
Term
| What are some characteristics of the P(r)conformation |
|
Definition
| Pr can only absorb red light and cannot activate cellular responses. Red Light converts Pr to Pfr |
|
|
Term
|
Definition
| beneficial substance metabolized by or incorporated into an organism |
|
|
Term
| Why would deficiency symptoms arise in plants |
|
Definition
| Deficiency symptoms may develop in plants that receive too little required nutrients |
|
|
Term
| What might plants do when there are not enough nutrients |
|
Definition
Scarcity of nutrients may- select for adaptations that help in acquisition,
– or trigger adaptive changes that aid in nutrient acquisition. |
|
|
Term
| Define essential nutrients |
|
Definition
| substances needed by plants in order to complete their reproductive cycle |
|
|
Term
|
Definition
| required in amounts of at least 1g/kg of plant dry matter |
|
|
Term
| Define micronutrients or trace elements |
|
Definition
| Those required in amounts at or less than 0.1g/kg |
|
|
Term
| Where does most plant dry mass originate from |
|
Definition
| Most plant dry mass originates from CO2 (carbon fixation) |
|
|
Term
| Why do plants often not obtain enough CO2 for maximal photosynthesis |
|
Definition
| Modern atmospheric CO2 is only 350 µl/L (0.035% of atmospheric content). 1,000 µl/L of CO2 is required to saturate photosynthesis. Oxygen can compete with CO2 causing photorespiration |
|
|
Term
| What percent of the mass of a plant does water account for |
|
Definition
| Typically 90% of weight of living plants |
|
|
Term
| Why is water essential in plants |
|
Definition
| Because it is used: -As a nutrient, source of most hydrogens and some oxygens in organic compounds (“reduced” carbon compounds). It is important for metabolic biochemical reactions (eg, hydrolysis). Its a solvent for other mineral nutrients. Its the main transport medium in plants |
|
|
Term
| List some plant macronutrients |
|
Definition
| nitrogen, potassium, calcium, magnesium, phosphorus, and sulfur |
|
|
Term
| List some plant micronutrients |
|
Definition
| chlorine, iron, manganese, boron, zinc, sodium, copper, molybdenum, and nickel |
|
|
Term
| List some defenciency symptoms in plants that resulting from lack of essential nutrients |
|
Definition
| Failure to reproduce, tissue death, and changes in leaf color, and Chlorosis – yellowing of leaves |
|
|
Term
| What element frequently limits plant growth, is required in large amounts for synthesis of amino acids, nucleotides, alkaloids, and many others and is the largest component in plants by weight after carbon, oxygen, and hydrogen |
|
Definition
|
|
Term
| What type of nitrogen can plants use |
|
Definition
| Although Earth’s atmosphere is 78% nitrogen (N2), plants can’t use this form. Nitrogen must occur in a “fixed” form such as ammonia (NH3), ammonium ion (NH4+) or nitrate ion (NO3-), Microorganisms oxidize ammonia to nitrate |
|
|
Term
| What is the most common form of nitrogen used by plants |
|
Definition
| Nitrate is the most common form most fixed nitrogen enters plants. Plasma membrane transporter proteins import nitrate into root cells. It is transported in xylem and can be stored in vacuoles |
|
|
Term
| How can new fixed nitrogen be added to the soil |
|
Definition
| New fixed nitrogen can be added by lightning, fire, air pollution and biological and industrial fixation |
|
|
Term
| Where does much of the fixed nitrogen in the soil come from |
|
Definition
| Much of fixed nitrogen in soil is recycled from compounds in other organisms |
|
|
Term
|
Definition
| atmospheric N2 combined with H to give NH3 |
|
|
Term
| List some organisms which fix nitrogen |
|
Definition
| It occurs by many types of cyanobacteria, other nonphotosynthetic bacteria also fix nitrogen. Symbionts transfer nitrogen directly to plant cells. |
|
|
Term
| What is needed to fix nitrogen |
|
Definition
| All nitrogen-fixing prokaryotes utilize large amounts of ATP and nitrogenase to fix nitrogen |
|
|
Term
| List two types of divine revelation |
|
Definition
| General Revelation and Special Revelation |
|
|
Term
| What are some things we should not do when integrating our faith with our religion |
|
Definition
| We should avoid shameful interactions (ad hominem attacks) with those of differing positions. We should not Abandon attempts to reconcile special and general revelation. We should not jumping to shallow, poorly considered conclusions |
|
|
Term
| How should we study biology |
|
Definition
| We must humbly realize the fallen-ness of our faculties, in terms of interpreting BOTH general revelation and special revelation, and in terms of our abilities to properly knit together the two. |
|
|
Term
| What should we persue tenaciously when studying biology |
|
Definition
|
|
Term
| What are some Christian views of Creation days |
|
Definition
| The 6-day view, the Day-Age view, The Analogical Days, and the Framework view |
|
|
Term
| What do all the Christian view of Creation days have in common |
|
Definition
| All reject unguided evolutionary mechanisms as the ultimate source of biological diversity |
|
|
Term
| Describe the 6 day Creation view |
|
Definition
| The view most often associated with a young earth, Earth viewed as 4-5000 years old. The most straightforward reading of the Genesis text. |
|
|
Term
| Describe the Day Age View |
|
Definition
| In Genesis the word used, “Yom” means age rather than literal 24-hr day. Scientific evidence of old earth suggests a different reading of Genesis. While the sequence of events is as layed out in Genesis is a historical account, the days are not 24-hour periods. |
|
|
Term
| Describe the Analogical Days View |
|
Definition
| Days are God’s work days, not identical to our work days (only analogous). Days are not of known length, may overlap or represent a logical rather than chronological breakdown of God’s creative activities. |
|
|
Term
| Describe the Framework View |
|
Definition
| This view is similar to analogical day view.Creation week is a metaphor, a poetic vehicle to communicate historical creation activities. Length of actual days is unspecified, and order and timing of events is viewed as unimportant. |
|
|
Term
| What does the proposed geological timescale predict the age of the earth to be |
|
Definition
| 4.55 billion year history |
|
|
Term
| How is the Sedimentary rock strata arranged |
|
Definition
| Sedimentary rock strata show distinctive assemblies of fossil organisms. Simpler organisms in deeper strata, more complex organisms in higher strata |
|
|
Term
| Give examples of radiometric dating of fossils |
|
Definition
Carbon 14- ratio of C12 to C14. (Assumes that production of C14 in upper atmosphere is constant.)
Potassium 40- Volcanic rock, ratio of potassium 40 to argon 40. |
|
|
Term
| What are some limits of radiometric dating |
|
Definition
| Limits- often require assumption about initial amounts present in a material; assume constant rates of radioactive decay. |
|
|
Term
| Define biological evolution |
|
Definition
| A heritable change in one or more characteristics of a population or species across many generations |
|
|
Term
| From a genetic perspective what does biological evolution involve |
|
Definition
| From a genetic perspective, involves changes in allele frequencies over time |
|
|
Term
|
Definition
| Viewed on a smaller scale, relating to genetic or phenotypic changes within a population over time |
|
|
Term
|
Definition
| •Viewed on a larger scale relating to formation of new species or groups of species= MACROEVOLUTION |
|
|
Term
|
Definition
| Group of related organisms that share a distinctive form, function. -Among species that reproduce sexually, members of the same species are capable of interbreeding to produce viable and fertile offspring |
|
|
Term
| Tell a little about Charles Darwin |
|
Definition
| He was a British naturalist born in 1809. He developed a theory of evolution, presented in 1858 at a meeting of the Linnaean society and published the ideas in 1859 (“The Origin of Species”) |
|
|
Term
| Who independently came up with a similar theory to Darwins |
|
Definition
| Alfred Russell Wallace independently came up with a similar theory, presented it alongside Darwin |
|
|
Term
| Who were some prominent Greek thinkers who influenced Darwin |
|
Definition
|
|
Term
| Describe Plato's idea of essentialism as is relates to evolution |
|
Definition
Variations of the ideal, “real” form
Evolution would not occur in a world of perfectly adapted creatures |
|
|
Term
| Descibe Aristotles view of Creation |
|
Definition
| an ordered “ladder of life” with each rung occupied. No room for change. |
|
|
Term
| Describe Natural Theology |
|
Definition
The Creator’s plan could be understood by studying nature. Adaptations of organisms were evidence that creatures were designed for a particular purpose.
Classification allowed an appreciation of the hierarchical steps on the ladder of life. |
|
|
Term
| Tell a little bit about Linneaus |
|
Definition
| Father of taxonomy. Came up with Classifications (Kingdom, Phylum, Class, Order, Family, Genus, Species) were not attempts to establish evolutionary relationships. Rather, “Deus creavit, Linnaeus disposuit” (God creates, Linneaus arranges) |
|
|
Term
|
Definition
| "Catastrophism" Interpreted fossil strata as a record of life’s history. Speculated that boundaries between fossil strata corresponded to the time of historical catastrophic events. Catastrophic events caused mass extinctions. Changes in species from one stratum to the next reflected immigration of organisms from other areas. |
|
|
Term
| Tell a little bit about James Hutton and Charles Lyel |
|
Definition
| Profound geological change due to slow, continuous processes that continue to operate in the world. Canyons form by slow erosion, fossil bearing strata slowly accumulate over time. Suggested old earth. |
|
|
Term
| Tell a little bit about Lamarck and his beliefs |
|
Definition
| (A drive toward complexity) Developed an early evolutionary model (1809) Organisms have the tendency to adapt and change in response to their environment. A continuous line of descent from simple ancient organisms to more complex modern organisms. Organs or structures not used deteriorate, organs or structures that aid in survival are retained and strengthened Adaptive changes in an organism are heritable (passed on to offspring) |
|
|
Term
| Tell a little bit about Thomas Malthus |
|
Definition
| a Anglican minister and “doomsday” economist. He suggested that unchecked population growth would inevitably lead to famine, disease and a ceaseless struggle for existence |
|
|
Term
| Describe selective breeding |
|
Definition
| Many traits are transmitted from parents to offspring. Selective breeding procedures designed to modify traits in domesticated species. Selected characteristics chosen by breeders, allowed to produce offspring |
|
|
Term
| Darwin thinking was influenced by the remarkable accomplishments of what kind of breeders |
|
Definition
| Darwin thinking influenced by the remarkable accomplishments of pigeon breeders. Might “natural” forces alter the features of living organisms over time? |
|
|
Term
| What was Darwin convinced of after reading Lyell’s Principles of Geology |
|
Definition
| After reading Lyell’s Principles of Geology, Darwin became convinced of the uniformitarian view of an ancient and changing earth |
|
|
Term
| What were some of Darwin's observations of the Voyage of the Beagle |
|
Definition
| South American flora and fauna were distinct from that found in Europe. Temperate South American flora and fauna were more similar to tropical South American flora and fauna than organisms in similar temperate climates in Europe. South American flora and fauna resembled fossil organisms in S. America. He was truck by distinctive traits of island species that provided them ways to better exploit their native environment |
|
|
Term
| What did Darwin see in Galapagos Island finches |
|
Definition
| He saw similarities in species yet noted that differences that provided them with specialized feeding strategies |
|
|
Term
| What was Darwin's conclusion after the Voyage of the Beagle |
|
Definition
| Descent with modification |
|
|
Term
| Describe descent with modification |
|
Definition
| Two separated populations of a species could diverge as each adapted to local conditions. Or, if environmental conditions change dramatically, a species’ characteristics could change over time. Over many generations, divergence could become pronounced enough to generate new species. |
|
|
Term
| What was Darwin's controversial assertion |
|
Definition
| Going far enough back in time, all species related through ancestral connections. |
|
|
Term
| If all individuals survive to reproduce to the extent they are capable of, populations would tend to grow exponentially. Environmental resources are often limited. What did Darwin conclude from this |
|
Definition
Reproductive activity can lead to a struggle for existence- not all individuals will survive this struggle.
It then makes sense that populations tend to remain stable in size over time (exponential increases are not typical) |
|
|
Term
| Variation in many observable traits abounds in populations of organisms. Much of this variation is heritable. What did Darwin conclude from this |
|
Definition
| Survival is not random, but may depend upon how well adapted an organism is to compete for resources. Best fit individuals will leave more offspring , Natural Selection. Populations will gradually change under the influence of natural selective pressures, will become better adapted for prevailing conditions. |
|
|
Term
|
Definition
| survival is not random, but may depend upon how well adapted an organism is to compete for resources. Best fit individuals will leave more offspring |
|
|
Term
| Did Darwin’s theory preceded Mendel’s genetics work |
|
Definition
| Yes, at the time of Darwins theory there was no conception of mechanism of inheritance. |
|
|
Term
| Genetics has allowed us to understand the relationship between what two things |
|
Definition
|
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Term
| Much of what we know about the history of life on Earth comes from |
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Definition
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Term
| What are some broad patterns of the fossil record |
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Definition
| Simpler forms in lower strata, more complex forms in upper strata. Fossils show that many changes suddenly appear; gradual changes are relatively rare. Punctuated equilibrium. |
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Term
| What two things describe the sudden apperance of fossils |
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Definition
• Fossils show that many changes suddenly appear; gradual changes are relatively rare. Punctuated equilibrium.
The Cambrian “explosion” and the lack ransitional forms |
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Term
| Do truly novel features of organisms often appear |
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Definition
| No, truly novel features of organisms appear infrequently. Most changes in fossil organisms involve alterations of structures that already exist in organisms from lower strata. |
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Term
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Definition
Suggested to be a “Transitional form” between fish and tetrapods; provides link between earlier and later forms. Had broad skull, flexible neck, eyes on top, primitive wrist and 5 fingers
Eye position would allow peeking above water to look for prey |
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Term
| What hypothesis was developed from the fact that fossil evidence suggests that, 200 mya, some oysters underwent shell changes. Smaller, curved shells were superseded by larger, flatter shells |
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Definition
| Flatter shells are more stable in disruptive water currents and so were better adapted if water currents became stronger |
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Term
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Definition
| Study of the geographical distribution of extinct and modern species |
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Term
| Define convergent evolution |
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Definition
| 2 different species from different proposed ancestral lineages show similar characteristics, occupy similar environments |
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Term
| What are some examples of proposed convergent traits |
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Definition
-Giant anteater and echidna both have long snouts and tongues to feed on ants
-Aerial rootlets for clinging in English ivy and wintercreeper
-Overall body form of dolphins and fish
-Antifreeze proteins in different very cold water fish |
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Term
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Definition
| Similarities between organisms attributed to common evolutionary ancestor. Many different categories of homology have been used to establish relationships between species. |
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Term
| Define anatomical homology |
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Definition
| Homologous physical structures are structures in different species proposed to be derived from a common ancestor |
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Term
| Gives some examples of anatomical homology |
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Definition
Same set of bones in the limbs of modern vertebrates proposed to have undergone evolutionary change to be used for many different purposes
-Vestigial structures are anatomical structures that have highly reduced or no apparent current function (but resemble functional structures of presumed ancestors)
-Ear wiggling muscles, tail bone, appendix in humans
- Pelvic bones in some snakes, whales |
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Term
| Define developmental homology |
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Definition
| Species that differ as adults often bear significant similarities during embryonic stages |
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Term
| Give some examples of developmental homology |
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Definition
-Notochord present in diverse chordate species
-Presence of branchial arches (gill ridges) in human embryos and fish embryos
-Teeth in embryonic baleen whales
-Human embryos have long bony tails |
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Term
| Define molecular homology |
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Definition
| Similarities in biochemical characteristics of cells suggest (to some!) that all life arose from a single common ancestor. |
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Term
| What do all living species use to store information |
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Definition
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Term
| Similar DNA (or amino acid) sequences that are thought to be inherited from a common ancestor are referred to as what |
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Definition
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Term
| Give some examples of biochemical reactions found in nearly all species |
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Definition
| the glycolysis pathway and, the Kreb’s cycle |
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Term
| What might Homologous genes (2 genes derived from the same ancestral gene) reveal |
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Definition
| May reveal possible molecular details of evolutionary change |
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Term
| 2 sequences of genes may be similar due to the same ancestral gene but not identical due to what |
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Definition
| Due to the independent accumulation of different mutations over time. |
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Term
| The longer the time since the hypothetical common ancestor, the greater the what |
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Definition
| The greater the divergence |
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Term
| How many known number of species are there |
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Definition
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Term
| Estimates of unidentified species range from what to whoat |
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Definition
| Estimates of unidentified species range from 2 to 100 million |
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Term
| Whats the difficulty in identifying a species |
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Definition
| A single species may exist in 2 distinct populations that may be thought to be in the slow process of evolving into 2 or more distinct species |
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Term
| What is the morphological species concept |
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Definition
| It says species are identified by having a unique combination of physical traits. Historically, it emphasized physical traits, but now extended to include DNA/protein sequence traits |
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Term
| What are some advantages of the morphological homology species concept |
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Definition
| It can be applied to all organisms, both asexual and sexually reproducing. Can be applied to extinct organisms |
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Term
| What are some drawbacks of the morphological homology species concept |
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Definition
| How many/which traits should be considered? Traits often vary in a continuous way, so where to draw the line? Members of the same species can look very different while members of a different species (defined in other ways) can look very similar |
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Term
| Define the biological species concept |
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Definition
| A species is a group of individuals whose members have the potential to interbreed with one another in nature to produce viable, fertile offspring but cannot successfully interbreed with members of other species. Its defined by reproductive isolation in natural environments (hybrids may be possible in artificial environments such as the laboratory or zoos). |
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Term
| What are two problems with the biological species concept |
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Definition
| It may be difficult to determine if 2 populations are truly reproductively isolated. It cannot be applied to asexual species, or extinct species |
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Term
| Define the evolutionary /phylogenetic/ cladistic species concept |
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Definition
| A species is derived from a single lineage that is distinct from other lineages and has its own evolutionary tendencies and historical fate |
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Term
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Definition
| A genetic relationship between an individual or group of individuals and its ancestors |
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Term
| What do species look like on phylogenetic trees |
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Definition
| Species are unbranched lines of phylogenetic trees |
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Term
| What is a drawback to the evolutionary /phylogenetic/ cladistic species concept |
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Definition
| Drawback – lineages difficult to examine and identify; oftentimes controversial. |
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Term
| Whats the ecological species concept |
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Definition
| Each species occupies a unique ecological niche |
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Term
| What is an ecological niche |
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Definition
| A unique set of habitat resources that a species requires, as well as its influence on the environment and other species |
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Term
| What do members within the same niche often do |
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Definition
| Within their own ecological “niche”, members of a given species compete with each other for survival |
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Term
| What is the ecological species concept good for |
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Definition
| Its useful for identification of asexually reproducing species, such as bacterial or protist species |
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Term
| What are some drawbacks of the ecological niche concept |
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Definition
| This concept depends on how fully the niche, needs of the organisms are known. Convergent evolution? |
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Term
| What are prezygotic barriers |
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Definition
| Barriers that prevent formation of zygote |
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Term
| What are postzygotic barriers |
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Definition
| Barriers that block development of viable, fertile individuals |
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Term
| Give some examples of prezygotic barriers |
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Definition
Habitat isolation (Geographic barrier prevents contact)
Temporal isolation (Reproduce at different times of the day or year)
Behavioral isolation (Behaviors important in mate choice ex.Changes in song)
Mechanical isolation (Size or incompatible genitalia prevents mating)
Gametic isolation (Gametes fail to unite successfully, important in species that release gametes into the water or air) |
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Term
| Give some examples of postzygotic barriesr |
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Definition
| Hybrid inviability, Hybrid sterility, and Hybrid breakdown |
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Term
| Define hybrid inviability |
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Definition
| fertilized egg cannot progress past early embryonic stages |
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Term
| Define hybrid sterility and give an example |
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Definition
interspecies hybrid viable but sterile
Mule example |
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Term
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Definition
| hybrids viable and fertile but subsequent generations have genetic abnormalities |
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Term
| Whats allopatric speciation |
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Definition
Proposed to be the most common source of cladogenesis (splitting of lineages)
Occurs when some members of a species become geographically separated, and then diverge. Can also occur when small population moves to a new location that is geographically separated: “founder effect” Genetic drift and natural selection may quickly lead to differences |
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Term
| What is proposed to be the most common source of cladogenesis (splitting of lineages) |
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Definition
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Term
| Define adaptive radiation |
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Definition
| A single species evolves into array of descendents that differ greatly in habitat, form or behavior |
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Term
| Define sympatric speciation and give some examples |
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Definition
| Its proposed to occur when members of a species that initially occupy the same habitat within the same range diverge into two or more different species. It involves abrupt genetic changes that quickly lead to the reproductive isolation of a group of individuals (otherwise, hybridization would erase the divergence) Example: Changes in chromosome number in plants |
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Term
| Define and describe autopolyploidy |
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Definition
| Non-disjunction of chromosomes during meiosis, self-fertilization. Tetraploid species formed (crossing with diploid would not produce fertile offspring). Observed by DeVries in primroses in early 20th century. |
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Term
| Define and describe alloplyploidy |
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Definition
| It results from cross fertilization between two species. A hybrid is produced that is most often sterile, but can reproduce asexually. May restore sexual reproduction through subsequent chromosome duplication ( to produce two chromosomes of each type). |
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