Term
|
Definition
-polar covalent w/ hydrogen bonds
-High specific heat
-solid form is less dense than liquid form
-ice held together in crystalline form
-uncharged->dissolves other polar and charged molecules well |
|
|
Term
|
Definition
-Proton donor
-High concentration of H+ ions
-a substance that reduces the OH- concentration in a solution
-pH less than 7 |
|
|
Term
|
Definition
-Proton acceptor
-a substance that reduces the hydrogen ion concentration in a solution
-a solution w/ a relatively high concentration of OH-
-pH greater than 7 |
|
|
Term
|
Definition
| -log[H+] where [H+] is the concentration of hydrogen ions given in units of molarity |
|
|
Term
| Hydroxyl (OH)-Functional group |
|
Definition
-contained in polar compounds such as alcohols and carbs
-Polar
-increases water solubility
-involved in hydrogen bonds |
|
|
Term
| Carbonyl (C=O)-functional group |
|
Definition
-polar
-double bond b/w C and O
-contained in aldehydes and ketones |
|
|
Term
| Carboxyl (COOH)-functional group |
|
Definition
-polar groups
-contained in carboxylic acids
-lose H+ ions to form acids like acetic acid
-have a negative charge when it becomes deprotonated
-fatty acids and amino acids have carboxyl groups |
|
|
Term
| Amino(NH2)-functional group |
|
Definition
-polar
-found in molecules like methylamine and amino acids
-can be primary, secondary or tertiary depending on hydrocarbon backbone placement
-can act as bases with primary amines becoming positively charged when protonated in molecules like amino acids |
|
|
Term
| Sulfhydryl (SH)-functional group |
|
Definition
-help stabilize proteins by reacting w/ each other to form cross bridges in the protein structure
-contained in thios like merccaptoethanol and cysteine |
|
|
Term
| Phosphates (PO4^2-) functional group |
|
Definition
-found in organic phosphates
-store energy that can be passed from one molecule to another by the transfer of a phosphate group
-DNA and ATP contain it |
|
|
Term
|
Definition
-C:H:O -> 1:2:1
-one carbonyl group
-spontaneously shifts b/w straight chain form and ring form
-can yield two different versions of the ring form called anomers->depends on the carbonyl oxygen is pointed one way or the other when it is attacked by the other side of the molecule |
|
|
Term
|
Definition
| when the carbonyl group is attached ti the carbon on the end of the chain |
|
|
Term
|
Definition
| when the carbonyl group is attached to one of the middle carbons on a saccharide |
|
|
Term
|
Definition
-sugars usually have 1+
-a carbon w/ 4 nonequivalent groups attached
-make sugars optically active |
|
|
Term
|
Definition
-form b/w simple sugars creating a larger sugar
-covalent bond |
|
|
Term
|
Definition
-carbs formed by joining many monosaccharides together into large polymers
-In glycogen, starch, and cellulose the glucose monomers are in the ring form |
|
|
Term
|
Definition
Glycogen->energy in animals
Starch->Energy in plants
Cellulose->Plant cell walls |
|
|
Term
|
Definition
Tryglycerides: energy storage
Phospholipids: cell membranes
Steroids: Hormones
Cholesterol: support membrane
Bile: digestion of fats |
|
|
Term
|
Definition
-very nonpolar
-hydrophobic
-composed of carbon, hydrogen and oxygen
-much lower oxygen content that carbs
-do not form polymers |
|
|
Term
|
Definition
-contain 3 fatty acids joined by ester linkages to one glycerol molecule
-Gather together to form globules inside fat cells that exclude water
-provide insulation and protection against injury |
|
|
Term
|
Definition
-lipid molecules w/ polar phosphate-containing "heads" and nonpolar fatty acid "tails"
-when mixed w/ water form structures with fatty acids gathered together to keep out water and the phosphate group pointing out toward water
-contain glycerol, two fatty acids, an phosphate group and a N-containing alcohol |
|
|
Term
|
Definition
-esters of fatty acids and alcohols
-form protective coatings |
|
|
Term
|
Definition
| -3 fused cyclohexane rings and one fused cyclopentane ring |
|
|
Term
|
Definition
-conjugated double bonds and carry 6-membered carbon rings at each end
-produce colors in plants and animals
-Subgroups: carotenes and xanthophylls |
|
|
Term
| Type of protein-Function-Examples |
|
Definition
1) Hormonal-chemical messengers-insulin, glucagon
2) Transport-transport of other substances-hemoglobin, carrier proteins
3) Structural-Physical support-collagen
4) Contractile-movement-actin/myosin
5) Antibodies-Immune defense-Immunoglobulins
6) Enzymes-Biological catalysts-amylase, lipase, ATPase |
|
|
Term
| Basic structure of proteins |
|
Definition
| -joining amino acids together (contain amino portion, carboxyl group, and R group), into a chain w/ peptide bonds, creates a string of amino acids-polypeptide |
|
|
Term
| Protein Levels of Structure: Primary |
|
Definition
-a linear sequence of amino acids, encoded by a gene
-doesn't describe any of the folding that occurs in the polypeptide chain but determines how the protein will fold and the side chains present |
|
|
Term
| Protein levels of structure: Secondary |
|
Definition
-regular coils or golds of the protein w/ nearby amino acids in the polypeptide chain interacting
-Alpha helix: spiral-shaped structure w/ different parts of the backbone forming H bonds in the spiral
-Beta-pleated Sheet: straight lengths of the polypeptide chain that lie one on top of the other to form a flat layer of structure |
|
|
Term
| Protein levels of Structure: Tertiary |
|
Definition
| -the interactions between different areas of the protein to form the overall 3D shape of a polypeptide |
|
|
Term
| Protein Levels of Structure: Quaternary |
|
Definition
| -the interactions between polypeptides in proteins with more than one subunit |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| the reactants in an enzymatic reaction |
|
|
Term
|
Definition
-lower the activation energy rate of a reaction
-increase the rate of the reaction
-do not affect the overall energy change of the reaction
-are not changed or consumed in the reaction |
|
|
Term
|
Definition
| the maximum amount of substrate in a reaction that continues to increase the rate of catalyzation, occurs because the number of active sites in a reaction are limited |
|
|
Term
| Induced fit model of an enzyme |
|
Definition
| the binding of a substrate alters the shape of the enzyme and active site |
|
|
Term
| The rate of an enzyme-related reaction may be changed by: |
|
Definition
-Concentration
-Temperature
-pH
-presence of coenzymes
-location of enzyme in a cell
-presence of inhibitors |
|
|
Term
| Temperature affects enzymes: |
|
Definition
-Low temps. enzymes have little activity because molecules take longer to find active sites and may not have sufficient kinetic energy to form the transition state
-Higher Temps. more likely to go into enzymes and have the energy to move into the transition state
-Too high-heat energy makes the enzyme denature :( |
|
|
Term
|
Definition
-acidity can alterate the charge of amino acids in the enzyme
-through changing the folding of the protein (unfolding of the enzyme at extreme acid or base conditions) |
|
|
Term
| Regulation of enzyme activity (non-protein ways) |
|
Definition
-make enzyme more available
-Increase amount of substrate
-inhibitors
-feedback inhibition |
|
|
Term
|
Definition
irreversible inhibitors: bind to an enzyme active site and covalently modify it to permanently cripple the enzyme molecule, more enzyme must be made
-competitive inhibitors: resemble the substrate and are able to displace the substrate from the active site, can overcome by adding more substrate
-non-competitive inhibitors: bind at a regulatory part of the enzyme molecule that transmits a change in structure through the enzyme molecule to reduce activity |
|
|
Term
| Enzymes regulated by other means that alter a protein's structure: |
|
Definition
1) activated by cleavage of one or more peptide bonds-cell makes precursor protein that is larger and inactive until after it is cut into smaller pieces by a protease
-modification of the amino acids w/ phosphate by protein kinases-particularily in response to extracellular signals that require a rapid response, phosphate is charged and negative and can alter the protein folding
-Phosphorylases-remove the phosphate to reverse the change in enzyme activity |
|
|
Term
|
Definition
| enzymes that hydrolyze peptide bonds |
|
|
Term
|
Definition
| adenosine triphosphate, each PO4 is negatively charged, and negative charges repel each other, many together creates lots of energy, when split, releases it |
|
|
Term
|
Definition
1) Glycolysis
2) Krebs cycle
3) Electron transport |
|
|
Term
|
Definition
-takes glucose, a sugar molecule with six carbon atoms, breaks it into two pyruvate molecules, each with three carbons, capturing energy in two different ways
-glucose is oxidized to form pyruvate, and some of the nergy is captured to make NADH, an energy carrier the cell uses to make ATP through electron transport: burning of fuels to extract energy, the fuel molecules become more and more oxideized, and have less energy, releasing their energy to their surroundings
-Glucose + 2Pi + 2 ADP + 2NAD+ -> 2 pyruvate + 2ATP + 2NADH + 2H+ + 2H2O
-occurs in the cytoplasem for both prokaryotic and eukaryotic cells |
|
|
Term
|
Definition
| -NADH is regenerated back to NAD+ in the absence of oxygen to allow glycolysis to continue to produce ATP, producing either ethanol or lactic acid as byproducts. |
|
|
Term
| Two types of fermentation |
|
Definition
-Ethanol fermentation: carried out by yeast in the absence of oxygen and is used to make beer and wine
-occurs when pyruvate is decarboxylated to become the two-carbon molecule acetaldehyde. NADH from glycolysis then reduces acetaldehyde to ethanol and is itself oxidized back to NAD+/ Regenerated NAD+ allows glycolysis to proceed
-Lactic acid fermentation: allows ATP production to continue when oxygen in the muscle is limited b/c it is consumed more rapidly than the blood stream can supply it; pyruvate is reduced to lactic acid by NADH that is oxidized to regenerate NAD+. The NAD+ then allows glycolysis to proceed |
|
|
Term
|
Definition
| -glucose is fully burned by the cell as an energy source, going through the Krebs cycle and electron transport |
|
|
Term
|
Definition
-pyruvate produced in the cytoplasm in glycolysis is transported through both mitochondrial membranes into the interior of the mitochondria. Pyruvate is converted into a two-carbon molecule called acetate, with the release of CO2 linked to a large carrier molecule called coenzyme A, to make acetyl-coenzyme. The oxidation of pyruvate to acetly-CoA also produces more NADH that will go on to make ATP.
-Pyruvate + CoA + NAD+ -> acetly-CoA + CO2 + NADH
-Acetyl-CoA enters the Krebs cycle by combining with a four-carbon intermediate to make the six-carbon citrate.
-2 CO2 mole. are produced and leave the cycle for every acetyl CoA
-Produces 3 NADH, one FADH2, and 1 ATP
-2 Acetyl-CoA + 6 NAD+ + 2FAD + 2 ADP + 2pi + 4 H2O -> 4 CO2 + 6 NADH + 2 FADH2 + 2 ATP + 4H+ + 2 CoA |
|
|
Term
|
Definition
-uses NADH and FADH2 to create a proton gradient
-located in inner mitochondrial membrand
-NADH and FADH2 transfer the high-energy electrons they carry to the chain and are oxidized back to NAD+ and FADH+. The high-energy electrons are transferred from one carrier to another. The carriers alternate b/w oxidized and reduced forms as they transfer electrons through the chain to the final electron acceptor at the end of the chain, oxygen, which is reduced to water
-energy is used at three points in the chain to pump H+ our of the mitochondrial interior. The pumping creates a pH gradient across the inner mitochondrial membrane.
-ATP synthase in the IMM harvests the energy to produce the ATP. ATP synthase allows the protons on the ouside of the mitochondria to flow down their concentration gradient back into the mitochondria
-ATP synthase harnesses the enrgy of proton movement down the gradient through ATP synthase itself to make ATP, making three ATP for every NADHthat enters electron transport and 2 ATP for every FADH2 that enters electron transport |
|
|
Term
|
Definition
| pores in the surface of a leaf through which carbon dioxide enters and oxygen exits the plant |
|
|
Term
|
Definition
| the dense fluid within the chloroplast in which carbon dioxide is converted into sugars |
|
|
Term
|
Definition
-energy from sun is used to produce glucose that can be burned in mitochondria to make ATP
-occurs in the chloroplast in plants
-occurs in the cytoplasm for cyanobacteria
-6CO2 + 12H2O + light -> C6H12O6 +6O2+ 6H20
-involves the reduction of CO2 to a carb to produce glucose
-made up of Light Reaction (thylakoid) and Calvin Cycle (stroma) |
|
|
Term
|
Definition
-chloroplasts are found mainly in the cells of the mesophyl (interior of the leaf)
-chloroplast has an inner and outer membrane and within the inner membrane, stroma.
-Interior of the chloroplast contains a series of membranes called thylakoid membranes that form stacks called grana |
|
|
Term
| Light Reactions (photosynthesis) |
|
Definition
-generates ATP, O2, and NADPH
-when photons strike cholorphyll, electrons are excited and transferred through the photosystems to a reaction center. The reactions are called photophosphorylation.
-Goes through cyclic or non-cyclic photophosphorylation, a proton gradient is produced.
-Protons flow down the chloroplast proton gradient back out into the stroma through an ATP synthase to produce ATP.
-The NADPH and ATP produced are used to complete photosynthesis. |
|
|
Term
| Cyclic Photophosphorylation |
|
Definition
-Conducted by Photosystem I
-Contributes to ATP production
-When chlorophyll is excited, the excited electrons pass through a system of electron carriers that pump protons to build a proton gradient.
-The proton is given back to chlorophyll to be excited again |
|
|
Term
| Noncyclic photophosphorylation |
|
Definition
-Uses Photosystems I and II
-Produces ATP, NADPH, and O2
-Excitation of chlorophyll in Photosystem II.
-Excited chlorophyll uses water as an electron donor, producing protons and oxygen
-Photosystem II then sends excited electrons through a chain of redox factors that use the energy to pump protons that will be used to make ATP
-At the bottom of the redox chain, electrons are donated to Photosystem I, which will excited the electrons and use their energy to make NADPH |
|
|
Term
| Calvin Cycle (dark cycle) |
|
Definition
-creates carbohydrates using the energy of ATP and the reducing power of NADPH
-Carbon used comes from atmospheric CO2 (carbon fixation)
-CO2 cominbes with ribulose biphosphate, a five-carbon sugar with two phosphate groups attached. The resulting 6-Carbon compound is split, forming 2 molecules of 3-phophoglycerate, a 3 carbon compound
-3-phosphoglycerate is then phosphorylated by ATP and reduced by NADPH which leads to the formation of glyceraldegyde 3-phosphate: starting pt. for making glucose |
|
|
Term
| Structure of DNA elucidated by |
|
Definition
|
|
Term
|
Definition
1) DNA is the genetic material, containing the genes that are responsible for the physical traits (phenotype) observed in all living organisms
2) DNA is replicated from existing DNA to produce new genomes
3) RNA is produced by reading DNA in a process called transcription
4) This RNA serves as the message used to decode and transmit the genetic information and synthesize proteins according to the encoded information. This process of protein synthesis is called translation. |
|
|
Term
|
Definition
-Adenine, Guanine, Thymine, Cytosine
-A pairs with T forming 2 H bonds
-G pairs with C, forming 3 H bonds |
|
|
Term
|
Definition
-a five-carbon sugar (deoxyribose)
-a phosphate group
-and a nitrogenous base that distinguishes it as A, G, T, or C |
|
|
Term
| Two types of Nitrogenous bases: |
|
Definition
-Purines: larger, two rings in each base, and include adenine and guanine
-Pyrimidines: one ring and are thymine and cytosine |
|
|
Term
|
Definition
-Nucleotides are polymerized: joined together in long regular strands of nucleotide building blocks
-Phosphate group on one nucleotide forms a covalent bond to the sugar group on the next nucleotide to make a phosphate-sugar backbone in the polymer with the nitrogenous base groups projecting to one side, exposed
-When a chain of nucleotides is polymerized, it always proceed from the 5' to the 3' w/ new nucleotides adding to 3' end.
-Each basepair must include one purine and one pyrimidine |
|
|
Term
|
Definition
-Two strands of DNA are separated one region at a time, and a new DNA strand is synthesized using each of the separated old strands as a template
-when process is complete, two copies of the genome have been generated by the enzyme DNA polymerase from one copy, with one complete copy of the genome for each daughter cell.
-Semi-conservative replication: one strand is conserved while a new strand is made from the template of the old strand
-DNA polymerase cannot start a DNA strand from scratch, so RNA primers are synthesized by a different enzyme, primase, and are later replaced by DNA |
|
|
Term
|
Definition
-begins at replication origins
-created two replication forks that move away resulting in bidirectional DNA replication
-All DNA must be replicated for the cell to pass through the next cell cycle checkpoint.
-Involves different forms of DNA polymerase that elongate DNA strands, adding nucleotides onto the end of a growing DNA chain using a complimentary DNA strand as a template to add nucleotides in the right sequence. |
|
|
Term
|
Definition
-DNA polymerases only add to end of an existing nucleotide chain, elongating it, and cannot start a new nucleotide chain
-DNA polymerases always synthesize a DNA chain in the 5' to 3' direction, adding onto the 3' end of a nucleotide chain
-DNA polymerases require single stranded DNA as a template, but cannot open up DNA to make it single-stranded |
|
|
Term
|
Definition
-Proteins bound at the replication origin recruit DNA helicase to open up the double helix
-Single-stranded DNA-binding proteins stabilize the opened region of DNA
-Short primer of RNA bound to DNA, add DNA onto the 3' end of the primer, synthesized by an RNA polymerase called primase that synthesizes a short stretch of RNA on the DNA template.
-Synthesize in opposite directions but locally 5'-3'
-One DNA strand is synthesized in a continuous polynucleotide called the leading strand
-The lagging strand is synthesized in smaller pieces (Okazaki fragments)
-RNA primer is removed from between the pieces and the gap filled in by another DNA polymerase
-Sections of DNA are joined together by ligase |
|
|
Term
| Problems w/ the ends of eukaryotic chromosomes: |
|
Definition
-DNA polymerase only works from 5' to 3', cannot copy both ends of linear eukaryotic chromosomes
-ends of eukaryotic chromosomes have special repeating sequences called telomeres, and telomerase that copies the telomeres from an RNA template it carries rather than the usual method |
|
|
Term
|
Definition
| -DNA polymerase detects errors in replication and fixes them, proofreading DNA as it replicates DNA and correcting the mistakes to form the correct base pairing |
|
|
Term
|
Definition
|
|
Term
|
Definition
| the use of multiple codons that encode the same amino acid |
|
|
Term
|
Definition
| the inability to produce the proper enzyme for the metabolism of phenylalanine |
|
|
Term
|
Definition
-cripples red blood cells and is the result of a change in a single amino acid in the hemoglobin gene.
-Traced to the presence of valine instead of glutamic acid |
|
|
Term
|
Definition
-a single nucleotide is substituted by another, an extra nucleotide is added or a nucleotide is deleted
-conservative if the amino change to an amino acid that is chemically similar |
|
|
Term
|
Definition
-addition/loss of base pairs
-changes the reading frame of the rest of the gene after mutation |
|
|
Term
|
Definition
-scientists use restriction enzymes
-the enzymes cute DNA in a way the leaves small segments of single-stranded DNA on the end
-if the sticky ends match, they join to make new DNA in a new location
-Ligase seals the DNAs together by covalently bonding |
|
|
Term
|
Definition
Restriction enzymes cut DNA, inserts it into a small circular bacterial DNA: plasmid
-Plasmid reintroduced into bacteria, bacteria becomes a vector |
|
|
Term
|
Definition
-Double-stranded except when replicating
-Deoxyribose sugar in the nucleotides
-Thymine base forms a thymine-adenine base bair
-Replicates DNA->DNA
-Only one type of DNA per organism. This DNA acts as the orginal source of information, acting like a master record. Its information is copied into RNA molecules |
|
|
Term
|
Definition
-Nearly always single-stranded
-Ribose sugar in nucleotides
-Uracil base instead of thymine. U-A
-Does not normally replicate (except in some viruses)
-Three types: mRNA, tRNA, rRNA |
|
|
Term
|
Definition
| carries messages that encode proteins |
|
|
Term
|
Definition
-ribosomal RNA
-a structural component of ribosomes |
|
|
Term
|
Definition
-transfer RNA
-carries amino acids to ribosomes to make proteins |
|
|
Term
|
Definition
-the process in which genes in the DNA genome are used as templates to produce mRNA messages for proteins
-RNA polymerase uses single-stranded DNA as a template to read the gene, matching base pairs as it synthesizes new RNA from the DNA template.
-RNA is synthesized from the 5' end to 3' end |
|
|
Term
|
Definition
-turned on or off by promoters (regions of DNA near the start of genes)
-Promoters bind transcription factors that regulate transcription of genes by RNA polymerase.
-Transcription factors bind to specific sequences of DNA in promoters to turn genes on and off in response to hormones or other signaling mechanisms |
|
|
Term
| Transcription-Eukaryotic Cells |
|
Definition
-mRNA is produced in the nucleus and is translated into proteins in the cytoplasm
-mRNA is usually modified in the nucleus w/ the addition of a cap to the 5' end, Poly A tail to 3' end and splicing |
|
|
Term
|
Definition
| introns are cut out, exons are joined together |
|
|
Term
| Prokaryotic cells: Translation |
|
Definition
-don't go through splicing
-transcription and translation occur in the same compartment at the same time, with ribosomes translating RNA before transcription is complete.
-prokaryotic genes are often found with several related genes next to each other in the genome and transcribed together in the same RNA molecule. This makes them polycistronic. |
|
|
Term
|
Definition
-the process in which the genetic code in mRNA is used to assemble amino acids in the correct sequence to make a protein
-occurs in the cytoplasm |
|
|
Term
|
Definition
-the mRNA is bound by a ribosome at the site on the mRNA where protein synthesis will begin.
-the start site is the codon AUG in the mRNA module which codes for the amino acid methionine |
|
|
Term
|
Definition
-activated to have a specific amino acid bound covalently at one end
-at the other end, has a three-base pair region called the anticodon that matches up and hybridizes to the correct codon in mRNA |
|
|
Term
| Aminoacyl-tRNA synthetases |
|
Definition
| attach amino acids to the correct tRNAs |
|
|
Term
|
Definition
1) Ribosome recognizes AUG
2) It matches with the next codon in the mRNA to the tRNA w/ the right anticodon
3) Ribosome joins aspartate to the end of the protein chain
4) mRNA moves down one codon and matches with tRNA again
5) Once the next tRNA is bound to the ribosome, the next amino acid is transferred from the tRNA to the end of the protein chain
6) The tRNA returns to the cytoplasm, the mRNA is translated again or chewed by enzymes |
|
|
Term
|
Definition
-occurs in ribosomes in cytoplasm or ribosomes bound to the Rough ER
-Proteins that will live in the cytoplasm are translated by cytoplasm
-proteins that will live in the ER golgi or plasma membrane are synthesized by ribosomes on the rough ER. Protein is synthesized, inserted into ER, tells ER where to send, packaged into vesicles, vesicles bring to Golgi, where proteins are modified and sent to plasma membrane |
|
|
Term
| Scientists that proposed that all life was composed of cells: |
|
Definition
| Matthias Schleiden and Theodor Schwann |
|
|
Term
| Scientist that proposed that cells only arise from other cells |
|
Definition
|
|
Term
|
Definition
-All living things are composed of cells
-All chemical reactoins of life occur in cells or in association with cells
-Cells arise only from preexisting cells
-Cells carry genetic information in the form of DNA. This genetic material is passed from parent cell to daughter cell |
|
|
Term
|
Definition
-no nucleus
-includes bacteria and cyanobacteria, unicellular organisms with a simple cell structure
-no membrane-bound organelles
-has ribosomes
-have an outer lipid bilayer cell membrane
-genetic material consists of a single circular molecule of DNA concentrated in an area of the cell called the nucleoid region
-respiration occurs at the cell membrane |
|
|
Term
|
Definition
-may be a prokaryote
-small circular extrachromasomal DNA containing few genes
-replicate independently from the rest of the genome and oftern incorporates genes that allow the prokaryotes to survive adverse conditions |
|
|
Term
|
Definition
| -have a cell wall, cell membbrane, cytoplasm, ribosomes, and flagella that are used for locomotion |
|
|
Term
|
Definition
-have a nucleus, membrane-bound organelles, and ribosomes
-include all multicellular organisms and all unicellular protists
-cytoplasm covers surrounding organelles |
|
|
Term
|
Definition
| a cell wall and chloroplasts |
|
|
Term
|
Definition
| centrioles, located in the centrosome area |
|
|
Term
|
Definition
-encloses the cell and exhibits selective permeability
-regulates the passage of materials into and out of the cell
-made of a phospholipid bilayer with a polar phosphoric acid region and a hydrophobic fatty acid region |
|
|
Term
| Scientists that discovered that the cell membrane was a phospholipid bilayer with fluid movement within the plane of the membrane: |
|
Definition
|
|
Term
|
Definition
-the site in which genes in DNA are read to produce mRNA, mRNA is spliced, and the DNA genome is replicated when the cell divides
-surrounded by a nuclear membrane
-contains the genome complexed with proteins called histones involved in packaging and regulating access to genes
-DNA packaged with histones is called chromatin and forms chromosomes |
|
|
Term
|
Definition
| -a dense structure within the nucleus in which rRNA synthesis occurs |
|
|
Term
|
Definition
-sites of protein production
-synthesized by nucleolus
-two subunits each composed of rRNA and proteins
-Free Ribosomes: cytoplasm
-Bound Ribosomes: ER
-Prokaryotes: similar function, but smaller |
|
|
Term
|
Definition
-a network of membrane-enclosed spaced connected at points with the nuclear membrane
-extends in sheets and tubes through the cytoplasm
-w/ ribosomes: Rough ER
-w/o: Smooth ER
-involved in the transport of proteins in cells, especially proteins destined to be secreted from the cell
-small regions of ER bud off to form vesicles that contain newly-synthesized proteins.
-then transported to the Golgi |
|
|
Term
|
Definition
-had ribosomes
-involved in protein synthesis
-proteins that are secreted, found in the cell membrane, the ER, or the Golgi are made by ribosomes from the RER
-proteins synthesized by the bound ribosomes cross into the cisternae or the RER |
|
|
Term
|
Definition
| -involved in lipid synthesis and the detoxification of drugs and poisons |
|
|
Term
|
Definition
-a stack of membrane-enclosed sacs
-receives vesicles and their contents from the ER
-modifies proteins through glycosylatiomn
-repackages proteins into vesicles and ships them to their next stop
-produces secretory vesicles that release their contents to the cell's exterior by exocytosis |
|
|
Term
|
Definition
-contain hydrolytic enzymes involved in intracellular digestion, degrading proteins, and structures that are worn out or not in use
-fuse with endocytic vacuoles, breaking down material ingested by the cells
-aid in renewing a cell's own components by breaking them down and releasing their molecular building blocks into the cytosol for reuse |
|
|
Term
|
Definition
| a cell in injured or dying tissue that ruptures the lysosome membrane, releasing its hydrolytic enzymes to digest its own cellular contents |
|
|
Term
|
Definition
-specialized containers for metabolic reactions
-Peroxisomes and Glyoxysomes |
|
|
Term
|
Definition
-contains oxidative enzymes that catalyze a class of reactions in which hydrogen peroxide is produced through the transfer of hydrogen from a substrate to oxygen
-break fats down into small molecules
-used in the liver to detoxify compounds |
|
|
Term
|
Definition
-found in the fat tissue of germinating seedlings
-used by the seedling to convert fats into sugars until the seedling is mature enough to produce its own supply of sugars through photosynthesis |
|
|
Term
|
Definition
-membrane-enclosed sacs within the cell
-formed after endocytosis and can fuse with a lysosome to digest their contents
-contractile vacuoles in freshwater protists pump excess water out of the cell
-plant cells have a large central vacuole called the tonoplast that stores organic compounds, inorganic ions, and wastes |
|
|
Term
|
Definition
-sites of aerobic respiration within the cell
-has and outer membranes that has many pores and allows molecules through on the basis of their size
-inner membrane has convolutions called cristae and a high protein content that includs the proteins of the ETC
-the area bounded by the inner membrane is known as the mitochondrial matrix and it is the site of many of the reactions in cell respiration
-contain their own circular DNA and ribosomes which enable them to produce some of their own proteins and they self-replicate via binary fission |
|
|
Term
|
Definition
| the belief that mitochondria developed from early prokaryotic cells that evolved a symbiotic relationship with the ancestors of eukaryotes and still retain vestiges of this earlier independent life. |
|
|
Term
|
Definition
-found only in algal and plant cells
-they function as the site of phtosynthesis
-contains its own DNA and ribosomes
-believed to have evolved via symbiosis |
|
|
Term
|
Definition
-composed of microtubules, microfilaments, intermediate fibers, and chains and rods of proteins
-gives the cell mechanical support, maintains its shape, and carries out cell motility functions |
|
|
Term
|
Definition
-hollow rods made of polymerized tubulin proteins
-when polymerized, radiate throughout cells and provide it with support and a framework for organelle movement within the cells
-centrioles and the mitotic spindle, which direct the separation of chromosomes during cell division,l are composed of microtubules |
|
|
Term
|
Definition
-specialized arrangements of microtubules that extend from certain cells and are involved in cell motility
-Prokaryotic flagellaare entirely distinct in structure from eukaryotic flagella |
|
|
Term
|
Definition
-cell movement and support are maintained in part through the action of solid rods composed of actin subunits (microfilaments
-move materials across the plasma membrane |
|
|
Term
|
Definition
| -collection of fibers involved in the maintenance of cytoskeletal integrity |
|
|
Term
|
Definition
-uniport: carry a single solute across membrane
-symport: translocate two different solutes simultaneously in the same direction, only occurs if both solutes bind to the proteins
-antiport: exchange two solutes by transporting one into the cell and the other out of the cell |
|
|
Term
|
Definition
| the net movement of dissolved particles down their concentration gradients |
|
|
Term
|
Definition
| -the net movement of dissolved particles down their concentration gradient with the help of carrier proteins in the membrane |
|
|
Term
|
Definition
-the net movement of dissolved particles against their concentration gradient with the help of transport proteins
-requires external energy and is necessary to maintain membrane potentials in specialized cells like neurons |
|
|
Term
|
Definition
| the simple diffusion of water from a region of lower solute concentration to a region of higher solute concentration |
|
|
Term
| Differences between passive transport and facilitated diffusion and active transport |
|
Definition
-passive transport: moves with the gradient, requires no protein, requires no external energy
-Facilitated: moves with the gradient, requires a protein, requires no external energy
-Active transport: moves against the gradient, requires a protein, requires external energy |
|
|
Term
|
Definition
| cell swells until it bursts |
|
|
Term
|
Definition
|
|
Term
|
Definition
| cell remains the same size |
|
|
Term
|
Definition
-cell membrane is invaginate, forming a vesicle that contains extracellular medium
-usually mediated by cell-surface receptors that are internalized along with the membrane vesicle |
|
|
Term
|
Definition
| the ingestion of liquids or small particles |
|
|
Term
|
Definition
the engulfing of large particles
-articles may first bind to receptors on the cell membrane before being engulfed |
|
|
Term
|
Definition
-a vesicle with the cell fuses with the cell membrane and releases its contents to the outside
-used for cells to release secreted proteins into their exterior
- |
|
|
Term
|
Definition
-small packages of nucleic acid in a protein coat that replicate themselves in cells
-a nucleic acid genome in the viral interior, surrounded by a protein coat called a capsid that protects the genome from the external environment and helps the viral genome to attach to cells and enter them.
-structure forms either a long tubular helix with the genome in the middle or a geometric icosahedral structure |
|
|
Term
|
Definition
-viruses that infect bacteria
-have complex tail assemblies composed of virus proteins that bind to the bacterial cell wall and inject the phage genome through the cell wall into the bacteria
-can either enter a lytic cycle or a lysogenic cycle |
|
|
Term
| Bacteriophage lytic cycle |
|
Definition
the phage uses the cell's machinery to produce new copies of the viral genome to make more virus
-viral proteins spontaneously assemble
-virus produces an enzyme to degrade the bacterial cell wall and burst the cell, releasing the newly synthesized viruses to infect neighboring bacterial cells |
|
|
Term
| Bacteriophage Lysogenic Cycle |
|
Definition
-phage does not begin to produce viral gene products, but is integrated into the bacterial genome where it remains hidden
-it can later excise itself and enter the lytic cycle |
|
|
