PBIO EXAM 3

Question 1

Energy

Answer 1

the capacity to do work

Question 2

Thermodynamics

Answer 2

the science of energy transformations

Question 3

Potential Energy

Answer 3

energy stored in an object?

Question 4

First Law of Thermodynamics

Answer 4

energy can be changed from one form to another but cannot be created or destroyed

Question 5

2nd Law of Thermodynamics

Answer 5

In all energy exchanges and conversions, if no energy leaves or enters the system under study, the potential energy of final state will always be less than the potential energy of the initial state.

Question 6

Entropy

Answer 6

a measure of the randomness or disorder of a system

Question 7

Open System

Answer 7

Life. energy in from the surroundings, energy out to the surroundings. Open system: order maintained.

Question 8

Close System

Answer 8

No energy in from the surroundings. Closed system: order becomes disorder

Question 9

Exergonic

Answer 9

energy out

Question 10

Endergonic

Answer 10

energy in

Question 11

Oxidation

Answer 11

the loss of a electron

Question 12

Reduction

Answer 12

is the gain of an electron

Question 13

Energy of activation

Answer 13

the energy that must be possessed by molecules in order to react is known as the

Question 14

Enzyme

Answer 14

a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction

Question 15

Catalyst

Answer 15

is substance that lowers the activation energy required for a reaction by forming a temporary association with the molecules that are reacting

Question 16

Substrate

Answer 16

the molecule on which an enzyme acts is known as its substrate

Question 17

Active Site

Answer 17

This portion of the enzyme is known as the active site

Question 18

Cofactor

Answer 18

One or more non-protien components require by enzymes in order to function many are metal ions; others are coenzymes

Question 19

Coenzyme

Answer 19

an organic molecule, or nonprotein organic cofactor, that plays an accessory role in enzyme-catakyzed processes, often by acting as a donor or acceptor of electrons; NAD+ and FAD are common coenzymes.

Question 20

Coupled Reactions

Answer 20

reactions in which energy-requiring chemical reactions are linked to energy-releasing reactions

Question 21

Metabolic Pathway

Answer 21

Each enzyme catalyzes one small step in an ordered series of reactions that together form a metabolic pathway. (Chains of enzymatic cascade reactions)

Question 22

Optimized Enzyme Working Environment

Answer 22

pH, temperature, and light

Question 23

Induced Fit

Answer 23

A change in conformation occurs when the substrate is bound.

Question 24

Lock and Key model

Answer 24

proposes that the enzyme’s active site and the shape of the substrate molecule are complementary to one another.

Question 25

Photosynthesis

Answer 25

conversion of light energy to chemical energy; the production of carbohydrates from carbon dioxide and water in the presence of chlorophyll by using light energy

Question 26

Photon

Answer 26

Elementary particle of light

Question 27

The Hill Reaction

Answer 27

the portion of the light reations in which electrons from water are transferred to an electron acceptor, reducing the acceptor

Question 27

Light-dependent reactions

Answer 27

Reactions happen in the thylakoid membrane of the chloroplasts and occur in the presence of sunlight

Question 28

Two Steps of photosynthesis

Answer 28

Light dependent reactions on thylakoid membrane (hill reactions, Z shceme, energy transduction reactions) Carbon Fixation reactions
2. Light independent reactions in stroma (the dark reactions, carbon fixation reactions) Energy transduction reactions

Question 29

The Z scheme

Answer 29

Photosynthetic electron transport. Describes the pathway of electron transfer from H2O to NADP+ that occurs during noncyclic electron flow, as well as the energy relationships

The Z scheme of photophosphorylation follows the following sequence: PS IIA→e−acceptorB→ETSB→PSIC→e−acceptorD→NADP+

Question 30

Energy transduction reactions

Answer 30

Reactions that in which energy change forms. Light reactions are a good example

Question 31

Carbon Fixed Reactions

Answer 31

In photosynthetic cells, the light independent ezymatic reactions concerned with the synthesis of glucose from CO2 ATP and NADPH. also called light independent reactions and dark reactions.

Question 32

light-independent reactions

Answer 32

Takes place within the stroma. It contains exzymes that work with ATP and NADPH to “fix” carbon from carbon dioxide into molecules that can be used to build glucose.

Question 33

dark reactions

Answer 33

is also called carbon-fixing reactions.

Question 34

Stroma

Answer 34

Stroma is the fluid filling up the inner space of the chloroplasts which encircle the grana and the thylakoids. In addition to providing support to the pigment thylakoids, the stroma are now known to contain chloroplast DNA, starch and ribosomes along with enzymes needed for Calvin cycle.

Question 35

thylakoids

Answer 35

each of a number of flattened sacs inside a chloroplast, bounded by pigmented membranes on which the light reactions of photosynthesis take place, and arranged in stacks or grana. They help absorb sunlight in order for photosynthesis to occur

Question 36

The main photosynthetic pigments

Answer 36

Chlorophylls, carotenoids, and phycobilins

Question 37

Chlorophylls

Answer 37

A (Blue, reflects green) B (Green reflects yellow?)

Question 38

Carotenoids

Answer 38

carotenes and xanthophylls
mainly as anti-oxidants.