Enzymes, P/Synthesis, Cellular Respiration

Question 1

What are catalysts?

Answer 1

Catalysts are substances which speed up the rate of a chemical reaction, without using itself up

Question 2

What is the substrate?

Answer 2

The substrate is the molecule that the enzyme acts on

Question 3

How is the active site formed?

Answer 3

Formed by folding of polypeptide chains to form a small region with a unique shape

Question 4

What happens if the shape of the active site is changed?

Answer 4

If the shape is altered by chemical or physical treatment the ability for the enzyme to function is reduced temporarily or permanently lost

Question 5

What is it called when the active site is permanently changed?

Answer 5

Denatured

Question 6

What is an enzyme with absolute or substrate specificity?

Answer 6

An enzyme can act on one substrate only

Eg.lactase

Question 7

What is an enzyme with bond specificity?

Answer 7

An enzyme can only act on a particular type of chemical bond

Eg. Peptide bonds

Question 8

What is an enzyme with group specificity?

Answer 8

An enzyme can only act on molecules with particular functional groups surrounding a bond

Question 9

How are enzymes stopped from acting at inappropriate times?

Answer 9

Many exist as inactive pro enzymes (zymogens) which are only activated in response to relevant signals, this prevents them causing damage

Question 10

What is monomeric enzyme?

Answer 10

Consists of a single polypeptide chain

Question 11

What is an obligomer?

Answer 11

Consists of two or more polypeptide chains, these are called subunits. The subunits can either be different or identical

Question 12

What is more common obligomer or monomeric enzymes?

Answer 12

Obligomer

Question 13

What is metabolism?

Answer 13

The sum of all chemical reactions that take place in cells

Question 14

What reactions breakdown?

Answer 14

Catabolic

Question 15

What reactions build up?

Answer 15

Anabolic

Question 16

What factors can effect the efficiency of enzymes?

Answer 16

Temp, pH, enzyme concentration, substrate concentration

Question 17

What is a competitive inhibitor?

Answer 17

Some compounds resemble the substrate molecules and they compete for the same active site

Question 18

What is rational drug design?

Answer 18

Biologists can work out the shape of many enzymes. They can design inhibitors that will stop certain enzymes from working.
Eg. Pain killers

Question 19

What are non-competitive inhibitors?

Answer 19

Non- competitive or allosteric regulators bind to a site that is seperate form the active site. The inhibitor changes the shape of the enzyme meaning the substrate is unable to bind to the active site.

Question 20

What are the inputs of p/s?

Answer 20

Carbon dioxide, water

Question 21

What are the outputs of p/s?

Answer 21

Glucose (simple sugar), oxygen

Question 22

What is a phototrophic organism?

Answer 22

Organisms that use sunlight to produce organic molecules eg. Sugar

Question 23

What is autotrophic?

Answer 23

Turns simple compounds to organic compounds

Question 24

What is an organic compound?

Answer 24

Carbon containing molecules

Question 25

What is a producer?

Answer 25

Producers are organisms which have the ability to synthesise light for energy. Producer is another name for phototrophic organisms

Question 26

What is p/s?

Answer 26

The process in which light energy is transformed into chemical energy stored in organic molecules such as sugars

Question 27

Where does the light dependent phase occur?

Answer 27

The thylakoid membrane of a chloroplast

Question 28

Where does the light independent phase occur?

Answer 28

In the stroma of a chloroplast

Question 29

What comes first the light dependent or independent stage?

Answer 29

Dependent

Question 30

Does the light dependent stage require light?

Answer 30

Yes

Question 31

What are the two main actions that the electrons in the E.T.C do?

Answer 31

- pump H+ ions into the thylakoid space | - produce energy to form a new molecule NADPH

Question 32

How are electrons that have been used in the E.T.C replaced?

Answer 32

From water

Question 33

What is the process where water molecules are split called?

Answer 33

Photolysis

Question 34

What does the process of photolysis produce?

Answer 34

Hydrogen, oxygen and electrons from the water

Question 35

What energy source is used during photolysis?

Answer 35

Light energy

Question 36

What is the waste product of photolysis?

Answer 36

Oxygen

Question 37

What does ADP stand for?

Answer 37

Adenosine Diphosphate

Question 38

What does ATP stand for?

Answer 38

Adenosine Triphosphate

Question 39

What does Pi stand for?

Answer 39

Inorganic phosphate

Question 40

What are stacks of thylakoid called?

Answer 40

Grana

Question 41

Where is the higher concentration of chloroplasts?

Answer 41

Towards the surface as there is more sunlight penetration

Question 42

What affects the rate of P/S?

Answer 42

- light intensity - type of light (wave lengths) - Carbon dioxide availability - water availability - temperature

Question 43

What are the inputs of aerobic respiration?

Answer 43

Glucose and oxygen

Question 44

What are the outputs of aerobic respiration?

Answer 44

Carbon dioxide, water and ATP

Question 45

What is cellular respiration?

Answer 45

Cellular respiration is a catabolic energy yielding pathway. It is a process by which organisms breakdown energy rich molecules to be used to make ATP.

Question 46

What are the major organelles used in cellular respiration?

Answer 46

Mitochondria and cytoplasm

Question 47

Where does glycolysis occur?

Answer 47

Cell cytosol

Question 48

Where does the transition reaction occur?

Answer 48

In the mitochondrial matrix

Question 49

Where does the kreb cycle occur?

Answer 49

In the mitochondrial matrix

Question 50

Where does E.T.C occur in cellular respiration?

Answer 50

In the mitochondrial cristae

Question 51

What are the two main functions of glycolysis?

Answer 51

- Produce ATP and NADH | - produces pyruvate

Question 52

What are the inputs of glycolysis?

Answer 52

Glucose

Question 53

What are the outputs of glycolysis?

Answer 53

2 NADH, 2ATP, 2xPyruvate

Question 54

What is the transition reaction?

Answer 54

Links pyruvate with the kreb cycle. The pyruvate is taken into the matrix and converted to Acetyl Coenzyme A (CoA)

Question 55

What is the feed molecule of the Kreb cycle?

Answer 55

CoA

Question 56

How many cycles is required for the Kreb cycle to completely breakdown a molecule of glucose?

Answer 56

Two

Question 57

What does two turns of the Kreb cycle produce?

Answer 57

- 4 carbon dioxides - 2 ATP - 6 NADH + H+ - 2 FADH + H+

Question 58

At what stage of cellular respiration is oxygen used?

Answer 58

E.T.C

Question 59

What energy is used to power pumps on the membrane during E.T.C?

Answer 59

Energy from electrons carried by NADH +FADH

Question 60

What do the proteins in the E.T.C pump?

Answer 60

H+ ions form one side of the membrane to the other

Question 61

Where does the Calvin cycle occur?

Answer 61

In the stroma

Question 62

What are the inputs of the light independent stage?

Answer 62

Carbon dioxide, NADPH, ATP, RuBP

Question 63

How many turns of the Calvin cycle is required to synthesis a sugar molecule

Answer 63

2 turns

Question 64

What is another name for the Calvin cycle?

Answer 64

Carbon fixation

Question 65

What happens at the end of ETC?

Answer 65

Oxygen molecules pick up excess electrons to form water

Question 66

What is the main purpose of P/S?

Answer 66

Convey radiant energy into chemical energy

Question 67

What does fermentation of yeast produce?

Answer 67

Ethanol and carbon dioxide

Question 68

What is anaerobic respiration?

Answer 68

Is a cellular process in which glucose is broken down in the absence of oxygen

Question 69

What are the outputs of glycolysis in cellular respiration?

Answer 69

2ATP, 2NADH

Question 70

What are the outputs of the Kreb cycle?

Answer 70

2ATP, 4 carbon dioxide, 6NADH, 2FADH

Question 71

What are the outputs of ETC in cellular respiration?

Answer 71

32ATP, water

Question 72

What is a cofactor?

Answer 72

A molecule which binds to the substrate in order to fit an active site

Question 73

What is the waste product of anaerobic respiration in animal cells?

Answer 73

Lactic acid

Question 74

What is the linking factor between P/S and cellular respiration?

Answer 74

Glucose

Question 75

Metabolic reactions that release energy are said to be?

Answer 75

Exergonic

Question 76

Metabolic reactions that require energy are said to be?

Answer 76

Endergonic

Question 77

What are the two types of reversible inhibitors?

Answer 77

Competitive and non-competitive

Question 78

How does rising temp affect the rate of reaction of enzymes?

Answer 78

For most chemical reactions an increase in temp causes an increase in reaction rate.

Question 79

Why does the reaction rate increase when temp is higher?

Answer 79

Because the particles move faster and are more likely to collide with each other.

Question 80

What happens to an enzyme once it’s on the too high side of their optimum temp?

Answer 80

On the other side of optimum is a range of temps at which enzymes will still operate but at a decreasing effectiveness till ultimate denaturing

Question 81

What happens to enzymes if temps fall too low?

Answer 81

If temps fall too low the enzymes and substrates do not have sufficient energy to interact. Enzymes that have been inactivated due to low temps can be activated again once temp rises.

Question 82

How do enzymes affect the rate of reaction?

Answer 82

Enzymes lower the energy level required and increase the reaction rate

Question 83

What is another name for the Kreb cycle?

Answer 83

Citric Acid cycle

Question 84

Does the Kreb cycle belong to p/s or cellular respiration?

Answer 84

Cellular respiration

Question 85

Where would rubisco be expected to be found in high concentration?

Answer 85

Stroma

Question 86

What is the role of oxygen as an output of the light dependent stage?

Answer 86

Released as a product

Question 87

What is the role of ATP as an output of the light dependent stage?

Answer 87

Provides energy for the light independent stage

Question 88

Are coenzymes organic or inorganic?

Answer 88

Organic

Question 89

What is the role of NADPH as an output of the light dependent stage?

Answer 89

Supplies energy and hydrogen ions for the light independent reactions

Question 90

Once NADH offloads it’s hydrogen and electrons it would

Answer 90

Collect more hydrogen from the breakdown of molecules in the Kreb cycle

Question 91

What are the similarities between chloroplasts and free living prokaryotes?

Answer 91

- both have ribosomes - circular DNA - double membranes

Question 92

During photosynthesis the splitting of water occurs when and where?

Answer 92

In the grana of the light dependent stage

Question 93

Is the Kreb cycle apart of photosynthesis or cellular respiration?

Answer 93

Cellular respiration

Question 94

Is the Calvin cycle apart of photosynthesis or cellular respiration?

Answer 94

Photosynthesis

Question 95

Are anabolic reaction exergonic or endergonic?

Answer 95

Endergonic