Mid Year Review Part 2

Question 1

What monomers are needed to build a protein?

Answer 1

Amino Acids

Question 2

What part distinguishes one amino acid from another amino acid?

Answer 2

The R-group distinguishes one amino acid from another amino acid.

Question 3

Define Primary (protein structure) and give examples

Answer 3

Primary – linear sequence of amino acids for a particular protein (like the sequence of letters that make up a particular word

Question 4

What characteristic is crucial for the proper functioning of a protein?

Answer 4

Shape

Question 5

What does “denaturing” a protein mean?

Answer 5

Shape has been disrupted by some means (usually excessive heat)

Question 6

What is the name of the bond that holds two amino acids together?

Answer 6

Peptide

Question 7

Most enzymes are what type of macromolecule?

Answer 7

Proteins

Question 8

What term describes when an enzyme’s (or any protein’s) shape is disrupted?

Answer 8

Denaturation

Question 9

What is the purpose of enzymes?

Answer 9

To catalyze (speed up) chemical reactions by lowering the barrier of activation energy

Question 10

What is the name of the region on the enzyme that binds to the substrate?

Answer 10

Active site

Question 11

What does it mean that enzymes have an optimal temperature and an optimal pH?

Answer 11

Optimal temp and optimal pH refer to the range of temperatures and pH a particular enzyme will work best in. Outside the range the enzyme will decrease in terms of how it can perform. (Slow down or denature)

Question 12

How are competitive and noncompetive inhibition the same? How are they different?

Answer 12

They are similar in that the decrease an enzyme’s activity by interfering with the binding of substrate to the active site.
They are different because a competitive inhibitor will plug up an active site and block substrate from getting in while a noncompetitive inhibitor will bind to a site other than the active site. But by binding to that other site, the shape of the active site will change and prevent substrate from binding.

Question 13

Are enzymes used up in a chemical reaction?

Answer 13

No; they can be used over and over again to speed up specific chemical reactions.

Question 14

Do enzymes normally participate as a reactant or product in a chemical reaction?

Answer 14

Neither

Question 15

Like all proteins, an enzyme’s function is highly dependent upon its _____________________.

Answer 15

Shape

Question 16

Enzymes speed up chemical reaction by lowering _________________.

Answer 16

Activation energy

Question 17

Why would a substance resist spontaneous breakdown?

Answer 17

Barrier of activation energy is too high

Question 18

I want to know whether a particular inhibitor acts by competition or noncompetition. If I add more substrate, I will only affect ______________________ inhibition.

Answer 18

competitive

Question 19

What does it mean if an enzyme is saturated?

Answer 19

All active sites of the enzyme are occupied (“saturated”) with substrate

Question 20

If an enzyme is saturated and I want a faster yield of product, what can I do?

Answer 20

Add more enzyme (because this will increase the number of available of active sites).

Question 21

What are the phases of the cell cycle?

Answer 21

Interphase (G1, S/DNA synthesis, G2) and Mitotic phase (Mitosis and Cytokinesis)

Question 22

In which phase of the cell cycle does the DNA content of the cell double?

Answer 22

S phase

Question 23

What are the four stages of mitosis?

Answer 23

Prophase, Metaphase, Anaphase, Telophase

Question 24

Identify the major events of Prophase

Answer 24

centrioles move apart; formation of mitotic spindle; chromatin starting to condense

Question 25

Identify the major events of Prometaphase

Answer 25

mitotic spindle fully formed; sister chromatids are visible; nuclear membrane is broken down and nucleolus has disappeared

Question 26

Identify the major events of Metaphase

Answer 26

sister chromatids line up at equator of cell (metaphase plate)

Question 27

Identify the major events of Anaphase

Answer 27

sister chromatids separate

Question 28

Identify the major events of Telophase

Answer 28

spindle breaks down; nuclear envelope reforms; nucleoli reappear; chromosomes unwind and are going back to chromatin (prophase in reverse)

Question 29

Define cytokinesis

Answer 29

happens just after telophase and divides cytoplasm to newly created cells

Question 30

What is a cleavage furrow?

Answer 30

The pinching in of the cell at the conclusion of mitosis; the pinching in results in a groove; only present in animal cell mitosis

Question 31

What happens in G1?

Answer 31

DNA content has not doubled

Question 32

What happens in S phase?

Answer 32

DNA content is in the process of doubling

Question 33

What happens in cytokinesis?

Answer 33

DNA content and cytoplasm is in the process of dividing itself

Question 34

Where does glycolysis take place?

Answer 34

cytoplasm

Question 35

Where does the citric acid cycle take place?

Answer 35

matrix of mitochondria

Question 36

Where does the Oxidative Phosphorylation take place?

Answer 36

inner mitochondrial membrane

Question 37

Can glycolysis proceed with oxygen or without oxygen?

Answer 37

It can proceed with or without oxygen

Question 38

What is the starting substance of glycolysis?

Answer 38

Glucose

Question 39

What are the products of glycolysis?

Answer 39

2 pyruvate, 2 NADH, 2 ATP

Question 40

What does the energy investment phase of glycolysis refer to? What does the energy payoff phase of glycolysis refer to?

Answer 40

The first half of glycolysis and its reactions require the use of 2 ATP molecules while the second half of glycolysis produces 4 ATP and 2 NADH; you invest energy in the beginning of glycolysis but the second half pays off by gaining 4 ATP and 2 NADH

Question 41

List three reasons why glycolysis is considered an ancient metabolic pathway?

Answer 41

Happens virtually in all cells, Does not require oxygen, Does not take place in an organelle

Question 42

Pyruvate is oxidized to this molecule if it enters the mitochondria.

Answer 42

Acetyl CoA

Question 43

What molecule is found at the end of the ETC and is the ultimate acceptor of electrons when they finish their journey along the ETC?

Answer 43

oxygen

Question 44

Where do we find the ETC proteins?

Answer 44

inner membrane of mitochondria

Question 45

Detail the steps of oxidative phosphorylation.

Answer 45

1. NADH or FADH2 drop off electrons to first protein of ETC 2. electrons are passed along the ETC releasing energy to actively transport hydrogen ions from the matrix to the intermembrane space 3. a concentration gradient of H+ ions is built up; high H+ exist in the intermembrane space and low H+ exists in the matrix 4. H+ comes back to matrix via facilitated diffusion through ATP synthase 5. Hydrogen ions going through ATP synthase provide ATP synthase energy needed to make ATP

Question 46

Hydrogen ions are actively transported to the _____________________ from the ___________.

Answer 46

intermembrane space; matrix

Question 47

Where is ATP synthase located?

Answer 47

Inner membrane

Question 48

What products are made as a result of yeast cells undergoing fermentation?

Answer 48

Ethanol and carbon dioxide

Question 49

What products are made as result of animal cells undergoing fermentation, resulting in muscle fatigue and soreness?

Answer 49

Lactic Acid

Question 50

What is the source of oxygen in photosynthesis?

Answer 50

Water

Question 51

What is the ultimate source of energy that drives photosystem?

Answer 51

Light energy

Question 52

Where do the light reactions of photosynthesis occur?

Answer 52

Thylakoid membranes

Question 53

Where does the Calvin Cycle occur?

Answer 53

Stroma

Question 54

What are the products of the light reactions?

Answer 54

ATP, NADPH, oxygen

Question 55

What are the products of the Calvin Cycle?

Answer 55

Sugar, ADP, NADP+

Question 56

Why do most plants appear green to our eyes?

Answer 56

Green light is reflected by chlorophyll a

Question 57

What light is least effective for driving photosynthesis?

Answer 57

Green

Question 58

Identify some accessory plant pigments. What is the purpose of accessory plant pigments?

Answer 58

Chlorophyll b, carotenoids; to absorb light that chlorophyll can't

Question 59

What pigment is found in the photosystem’s reaction center?

Answer 59

Chlorophyll a

Question 60

What replaces electrons that leave PSII?

Answer 60

Water (splitting it to release electrons as well as oxygen)

Question 61

What replaces electrons that leave PSI?

Answer 61

The electrons that travel down the ETC from PSII

Question 62

Do humans have chloroplasts?

Answer 62

no

Question 63

Do plants have mitochondria?

Answer 63

yes

Question 64

Define Secondary (protein structure) and give examples

Answer 64

Secondary – folds and coils due to hydrogen bonding (alpha helix and beta pleated sheet)

Question 65

Define Tertiary (protein structure) and give examples

Answer 65

Tertiary – overall 3-D shape of protein (includes hydrogen bonds, disulfide bridges, ionic bonds, covalent bonds)

Question 66

Define Quaternary (protein structure) and give examples

Answer 66

Quaternary – two or more polypeptides interacting together (like collagen or hemoglobin)