Bio 190 exam 4

Energy from sun and carbon from CO2 (photo/auto troph)
Energy from sun and carbon from organic compounds (photo/hetero troph)
Energy from chemical compounds and carbon from CO2 (chem/auto troph)
Energy from chemical compounds and carbon from organic compounds (chem/hetero troph)

Endergonic reactions = product has more energy than reactant
Exergonic reactions = product has less energy than reactant

Activation energy is the input of energy needed to start a chemical reaction.
Catalysts are substances that lower the activation energy of a reaction

Adenosine Triphosphate is good for transporting energy around the cell because it’s small and has a high energy bond. It’s made up of phosphate groups, ribose, and adenine and releases potential energy when hydrolyzed.

Enzymes are biological catalysts.

Feedback inhibition is when the end product of a chain of enzymes inhibits the initial enzyme in the chain, essentially shutting off production once there’s enough of the product.

Chloroplasts are organelles made up of an outer an inner membrane, thylakoids (stacked in grana), the lumen, all of which float in the stroma. Chloroplasts are the site of photosynthesis.

Photosystem II (PSII) – Photons hit chlorophyll in PSII, where water splits and releases electrons that are excited by the photons. O2 is a byproduct of this reaction, alongside hydrogen ions (H+)

The 1st electron carrier moves excited electrons from PSII to the cytochrome complex.

Cytochrome complex – Protons are moved into the lumen using energy from the excited electrons

The 2nd electron carrier moves electron from the cytochrome complex to PSI (this electron carrier moves inside the lumen)

Photosystem I – The electrons are re-excited by photons hitting chlorophyl in PSI after losing most of their energy in previous steps. The electrons are passed to the third electron carrier and either interact with NADP+ to form NADPH or are recycled.

ATP synthase – ATP synthase uses the potential energy held in the proton gradient across the thylakoid membrane (created by PSII and the cytochrome complex) to combine ADP and inorganic phosphate (Pi) to form ATP.

Outcomes – Oxygen was released as a byproduct of PSII, and NADPH and ATP have been created. The ATP and NAADPH.

Photons hit chlorophyll in PSII, where water splits and releases electrons that are excited by the photons. O2 is a byproduct of this reaction, alongside hydrogen ions (H+)

Protons are moved into the lumen using energy from the excited electrons

The electrons are re-excited by photons hitting chlorophyl in PSI after losing most of their energy in previous steps. The electrons are passed to the third electron carrier and either interact with NADP+ to form NADPH or are recycled.

ATP synthase uses the potential energy held in the proton gradient across the thylakoid membrane (created by PSII and the cytochrome complex) to combine ADP and inorganic phosphate (Pi) to form ATP.

No, it was anoxygenic

The light reactions produce ATP and NADPH, which hold energy in their chemical bonds that’s used in the Calvin cycle.

ATP synthase uses the potential energy held in the proton gradient across the thylakoid membrane (created by PSII and the cytochrome complex) to combine ADP and inorganic phosphate (Pi) to form ATP.

The Calvin cycle takes place in the stroma (watery area similar to cytosol)

Phase 1 (fixation) – inorganic carbon in the form of CO2 undergoes carbon fixation and is incorporated into organic molecules. This involves 3 CO2 reacting with 3 RuBP to produce 6 3-PGA. This reaction is catalyzed by an enzyme called RuBisCO.

Phase 2 (reduction) – The 6 molecules of 3-PGA produced in phase 1 use 6 ATP and 6 NADPH (produced in the light dependent reactions) to generate 6 G3P.

1 G3P leaves the cycle to be used for other organic molecules. - PRODUCT

Phase 3 (regeneration) – A large set of reactions uses the other 5 G3P and energy from 3 ATP to produce 3 RuBP, starting the process again.

Inorganic carbon in the form of CO2 undergoes carbon fixation and is incorporated into organic molecules. This involves 3 CO2 reacting with 3 RuBP to produce 6 3-PGA. This reaction is catalyzed by an enzyme called RuBisCO.

The 6 molecules of 3-PGA produced in phase 1 use 6 ATP and 6 NADPH (produced in the light dependent reactions) to generate 6 G3P.
1 G3P leaves the cycle to be used for other organic molecules.

A large set of reactions uses the other 5 G3P and energy from 3 ATP to produce 3 RuBP, starting the process again.

Catalyze carbon fixation.

C4 plants – move the Calvin cycle into bundle sheath cells, hiding it away from O2. Mesophyll cells fix CO2 into a 4C product and move to Bundle Sheath cells, creating a high concentration of CO2 in the bundle sheath for the Calvin cycle.

CAM plants – open stomata at night and grab CO2, store as C4, do calvin cycle at daytime, close stomata during the day and release high CO2

1-Glycolysis
2-Pyruvate Oxidation
3-Krebs Cycle
4-ETC and Chemiosmosis

Glycolysis breaks glucose into two pyruvate. Glucose is primed with phosphates using 2 ATP, cleaved into two pyruvate molecules, and 2 NADH and 4 ATP are generated. Since 2 ATP was used to prime the reaction, the net gain is 2 NADH and 2 ATP. (occurs in cytoplasm)

The 6 carbons begin in glucose and end with 3 carbons in each of the two pyruvates

The energy begins in glucose and ends in 2 ATP and 2 NADH

Pyruvate oxidation releases 2 CO2 molecules and produces 2 NADH molecules. One carbon is broken off of the Pyruvates and leaves as CO2, producing 2 Acetyl moleules and releasing a high energy electron. This electron attatches to a molecule of NAD (for stability,) generating NADH . The Acetyl attatches to CoA, generating Acetyl-CoA

The 6 carbon begins in 2 pyruvate molecules (3 carbon each) and ends in 2 acetyl-CoA molecules (2 carbon each) and 2 CO2 molecules (1 carbon each) leave the system.

The energy begins in 2 ATP molecules and 2 NADH molecules, and ends in 2 ATP molecules and 4 NADH molecules.

The krebs cycle captures the electron energy in the remaining carbons. The 2 Acetyl-CoA attatch to 2 Oxaloacetate to form 2 citric acid molecules (these are 6 carbon molecules, but much easier to break down than 2 carbon molecules). The citric acid undergoes a series of reactions, releasing a total of 4CO2, 2ATP, 2FADH2, and 6NADH by the end of the cycle

The 6 carbon begins in 2 Acetyl-CoA molecules and 2 CO2 molecules (already released), and ends in 6 CO2 molecules.

The energy begins in 2 ATP and 4 NADH molecules, and ends in 4 ATP, 10 NADH, and 2 FADH2 molecules.

Stage 4a – ETC (in which stored electrons are dumped on oxygen and an H+ gradient is created)
Stage 4b – Chemiosmosis (in which energy from a H+ gradient is used to link ADP+P into ATP)

The carbon starts in 6 CO2 molecules (already released), and ends in 6 CO2 molecules

The energy begings in 4 ATP, 10 NADH, and 2 FADH2 molecules, and ends in 38 ATP molecules (36 eukaryotes)

Yes

The reactants of respiration are nearly the same as the products of photosynthesis and vice-versa

The endoderm

Jaws evolved from gill arches (a pre-existing skeletal system used to pump water and grab prey)

Amylase breaks down starches (complex sugars) into simple sugars (in saliva)
Gastrin is a hormone that stimulates Hydrochloric Acid (CHl) production in the stomach
Pepsin is a protease (protein that breaks down proteins) (in stomach)

CCK stimulates gallbladder to release bile (bile breaks down fats) into the small intestine (proximity to small intestine)
Trypsin helps digest protein (protease) (in small intestine)
Secretin causes pancreas secretion (pancreas holds trypsin, lipase, and bicarbonate ions)

An inactive substance that’s converted into an enzyme when activated by another enzyme

Tight junctions form a selective barrier and prevent leakage
Villi/microvilli increase the surface area of the intestine for more efficient absorption

The large intestine reabsorbs water and nutrients from fecal matter, reducing it to a dried fecal pellet
A large microbiome also exists in the hindgut which, among other things, digests fiber etc.

Bowman’s capsule – kidney cells encase capillaries; blood filtrate enters
Proximal tubule – reabsorbs solutes (glucose, amino acids)
Loop of Henle – generates a salt gradient in kidney;
Descending - permeable to
water
Ascending – permeable to salt
Collecting duct – reabsorbs water

Concentrates nitrogenous waste in urine by generating a salt gradient in the kidney, saving water

The protein on the plasma membrane of collecting duct cells that reabsorbs water before it exits the nephron

Yes

A species that’s essential to an ecosystem. Without it, the ecosystem would drastically change.

They regulate herbivores. With too many herbivores there aren’t enough plants, and without enough plants the ecosystem falls apart. This is a trophic cascade.

Food webs Cycle matter and energy among organisms.
Producers – fix carbon and obtain energy to produce the 4 major biomolecules: protein, lipids, carbs, nucleic acids
Consumers – heterotrophs that depend on producers
Decomposers – return compounds into the environment
Productivity is the amount of biomass energy being added to an ecosystem/the rate its being added.

10% per trophic level

The stars

Biomass – Organisms
Atmosphere – Carbon dioxide
Ocean – Carbon dioxide, bicarbonate
Rocks – Calcium carbonate (limestone), fossil fuels

Short term – respiration and photosynthesis
Long term – sources and sinks

Movement between reservoirs
Volcanoes – output of carbon dioxide
Limestone – removes carbon dioxide
Subduction – into the mantle

Nitrogen fixation – making atmospheric nitrogen available to organisms
Bacteria fix nitrogen gas (N2)
into ammonia (NH3)
Nitrifying and Denitrifying
bacteria complete the cycle

Pooping and mixing

Era/time period during which humans are the dominant ecological force on the planet.

Our burning of fossil fuels to drive the economy has led to enormous greenhouse gas emissions, essentially cooking the globe

Fertilizers cause eutrophication (nutrient blooms that lead to anoxic environments and death)

We’ve spread invasive species all over the place

We’ve caused species like the passenger pigeon and the Carolina Parakeet to go extinct, and caused species like the Guanacaste tree to adapt a new reproduction method because the old one relied on extinct animals to spread seeds.

A genetic engineering tool that biases the inheritance of a specific gene or trait, regardless of natural selection.

More renewables, more land/ocean protected, coral reefs coming back, medicine improving, etc.