• Electron transport redox reaction
• Loss of electron, gain in charge = oxidation
• gain of electron, reduction in charge = reduction

• Cells regulate chemical reactions through the use of protein catalysts called enzymes
• Catalysts synthesized by living organisms almost all are proteins
• Enzymes are not consumed or permanently altered by reactions and are specific for a certain kind of reaction
• Peptide bond in protein enzyme are sensitive to pH and temperature
• Regulation (Noncompetitive): enzyme inhibitors, allosteric sites can activate or inactivate enzyme.
• Regulation (Competitive): exact same as non-competitive except the site is active, not allosteric

• Two series of reactions in photosynthesis: light and dark/dependent and light independent
• Using stored chemcial energy (ATP) to synthesize glucose
• Photons are used to excite electrons
• Pigments absorb the light and become oxidized, which releases the excited eletrons

• Photosystems, light harvesting units which consist of pigment molecules, capture high energy photons which excites electrons.
• Require sunglight
• Occurs in the thylakoid membrane.
• Photsystems have a reaction center and antenna molecules (chlorophyll b, carotenoids, phycocyannis)

• Antenna molecules absorb energy from photons
• Antenna molecules pass energy around until energy reaches the reaction center.
• chlorophyll a molecule (reaction center) releases excited electron to priammry electron acceptor ETC 1.
• Transfer of electron from chlorophyll a to primary electron acceptor = redox reaction.
• Primary electron acceptor gains an electron, , chlorophyll a loses one.
• this is from the splitting of water, which releases 2 H+ and 1 O atom. Two water molecules produce oxygen, THE ONLY TIME WHEN OXYGEN IS PRODuCED.

• Series of electron carrier molecules that shuttle elctrons from photosystem II to photosystem I.
• Also pumps protons by relseasing energy across the thylakoid membrane
• Protons transported from stroma to indise the thylakoid

• Energy released along ETC I is sued to actively transport protons across the thylakoid membrane
• Protons transported from stroma, then diffuse back into the stroma using ATP synthase, an enzyme in the thylakoid membrane
• Energy is then released, which is used to produce ATP from ADP
• Chemiosmisis yields ATP from ADP

• Electrons excited fro photosystem I reaction center (chlorophyll a)

• Electrons pass down ETC II
• Electrons captured at the end of the chain by NADP+ to form NADPH

• Organic molecules from carbon dioxide, this is the only place where carbon dioxide is used
• Energy is procided by ATP from chemiosmsis of the light reactions
• Electrons supplied by NADPH from photosystem I of the light reactions
• 6 Carbon dioxide are used to produce 12 glyceraldehyde, which is then used to build 1 glucose molecule + 6 rubisco.
• Alternate pathways of the dark reactions are adapted to weather condidtions that require the stomata to close (photosynthesis/transpiration complex)

• Plants use cellular respiration to release energy from carbs (glucose) they produce
• Animals use cellular respiration to release energ from carbs the consume
• Occurs in the mitochondria (except for glyocolysis)
• GLucose' energy is preserved and the molecule glucose in consumed

• The first stage, which occurs in the cytoplasm
• Occurs in the presence OR absence of oxygen
• 6 carbon glucose is converted into two 3 carbon molecules of pyruvate (pyruvic acid)
• Involves 10 enzyme catalyzed reactions.
• Yields 2 ATP, 2 NADH, and 2 Pyruvate (from glucose)

• Pyruvate is oxidized in the mitochondria
• NAD+ is reduced to NADH
• Carbon Dioxide is released
• Each of the two pyruvate molecules from glycolysis have become 2 carbon molecules (2 acetyl groups)
• Acetyl groups are carried to the Kreb's cycle by coenzyme A (making it acetyl CoA)
• Also produces 2 NADH and 2 Carbon Dioxide

CR: Kreb's cycle

• Only Acetyle group enters, the Coenzyme a is a taxi cab
• Takes place in the mitochondrial matrix and consists of 9 enzyme catalyzed reactions.
• Stage 1: acetyl binds to oxalocetate, producing a six-carbon molecule
• Stage 2: 2 carbons are removed as carbon dioxide
• State 3: the four carbon starting material, oxaloacetate, is regenerated
• Each glucose creates 2 acetyles, thus two turns of this cycle, when combined with the oxaloacetate, makes citric acid
• 2 ATP, 2 FADH, and 6 NADH

• NADH and fADH carry their high energy electrons to the inner mitochondrial membrane (the location of the transport chain)
• Transfer electrons to a series of membrane associated carriers, 3 of which are proteins that pump protons out of the matrix and into the membrane during the process
• ETC provides energy for the transport of protons which are essential for chemiosmosis

• The proton gradient induces the prodtons to retnter the matrix through ATP synthase channels
• The proton reentry drives the synthesis of ATP, most are produced here.

• Blood, which has hemolyph
• Heart pump
• Vessles for transport of the medium

• Open system: tissues and organs bathed in hemolyph; has a heart but vessels are minimal or absent; involves most invertebrates, mollusks and arthropods
• Close System: blood never contacts tussie, heart and exstensive network of blood vessels. Some invertebrates and all vertebrates

• One circuit: 2 chamber heart (atrium/ventricle)

• 3 chambers of heart (left atrium, right atrium and ventricle); separate circuit which goes between the heart and lungs
• mixing of oxgen and deoxygenated blood still occurs
• IE amphibians

• Arteries (contract): much thicker, more muscular walls; involves higher blood pressure
• Arterioles: branches off the arteries
• Venules
• Veins (valves)

Requirements:

• Respiratory surfaces are: moist, large in surface area, and surrounded by capillaries

• Aquatic Respiration: counter current gas exchange of oxygenated water over gill lamellae
• Terrestrial respiration: increasing compexity of the lung
• Mammalian respiration: nares.

Pharynx>larynx>trachea>

bronchi>brochiole>aveoli

• With gas transport, iron containing protein hemoglobin carries oxygen in the erythrocytes
• Negative pressure system: Diaphragm contracts and chest expands. Volume of the thoracic cavity and lungs increases, pressure below that of atmospheric pressure, which pulls are in
• Exhalation occurs when diaphragm relaxes

• Ingestion
• Digestion - mechanical and chemical
• Absorption - small intestine
• Elimination

• Some invertebrates, IE hydra
• One way digestive cavity; one opening used for both ingestion and elimination
• Essentially, digestion in a 'sack'

• One way tract has evolved
• Includes mouth, gut, and anus
• Specialixed regions allow nutrition to be extracted from more complex foods
• One digestive cavity (alimentary canal)
• This includes all vertebrates

• Mastication, for chewing
• Digestion of starch, as saliva contains amylase. Saliva also important for buffering and moisteing bolus
• Epiglottis at the back of the throat

• Muscular tube, moves food down via peristalsis, a propulsive muscular contraction
• Moves food in one direction down a longitudinal tube

• Muscular sac
• Parietal cells: secrete H+ acidity, which eliminates pathogens
• Chief cells secrete pepsin and aids in protein digestion
• Some mechanical digestion going on and acidity kills pathogens

• Has many tissue layers
• Serosa: outermost
• Muscularis
• Submucosa: rich in blood vessels
• Mucosa: villia folds
• Microvilli: hair like projection
• Consists of 3 parts: duodenum (receives secretions), the jejunum (most nutrients are digested and absorbed here)
• Ileum

• Aka colon
• Collects undigested material while absorbing water and minerals
• Vestigial Appendix
• Anything not absorbed in small intestine gets absrobed here

• Macromolecule metabolsim
• Detoxification
• Secretes bile salts for emulsifying fat

Gall bladder

• Stores intesified fat and sends it to the duodenum

• Controls glucose levels in the bood
• Secretes pH buffers and enzymes in the duodenum

• Filters blood which removes non-function red blood cells and controls infection
• Blood reservoir