Unit 2: Metabolism and Enzymes Flashcards Preview

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Flashcards in Unit 2: Metabolism and Enzymes Deck (38):
1

The sum of all the chemical reactions occurring in an organism.

metabolism

2

This refers to the breaking down of a molecule.

catabolism

3

This process releases “potential” E found in the chemical bond between monomers.
This is an exergonic reaction because it releases heat to the environment
Think Catastrophe; breaking up things.

Catabolism

4

type of reaction that releases heat into the environment

exergonic

5

This is the assembly of molecules.

anabolism

6

This process requires “Kinetic” E to position molecules in away so as to create a chemical bond between monomers.
This is an endergonic reaction because it absorbs energy from the environment.
Think Anabolic steroids; these build muscle.

anabolism

7

type of reaction that absorbs energy from the environment.

endergonic

8

For living organisms, the chemical E of life is found in ___________ _______.

chemical bonds

9

The processes of Cellular Respiration and Digestion ________ the E for use by cells.

release

10

Source of all E for Earth?

sun

11

Why is the sun the source of energy for Earth?

The process of photosynthesis allows plants to store this solar energy in the form of chemical energy (sugar).

12

The study of Heat E and its properties

Thermodynamics ((The study of Heat E (Thermo) and its properties (dynamics.))

13

What is the First Law of Thermodynamics (Also called the Principle of the Conservation of E)?

E cannot be created nor destroyed only transformed or transferred.

14

What is the Second Law of Thermodynamics?

Every E transfer increases the entropy of the universe.
Sunlight(high quality E) going in and heat (low quality E)coming out; it can’t do work.

15

means disorder; unable to do work because it is in a low state of order.

entropy

16

It is referred to as “free” because E is available to perform work. (Mainly making ATP or GTP in a cell.)
Not all E is available. (Some is lost as waste…like when we defecate…same goes for cells too.)
Most E is lost as Heat as a byproduct of the bonds being broken.

Gibbs Free E (represented as “G”)

17

3 types of work performed by living cells

mechanical, transport, metabolic

18

the type of work performed by living cell that is work outside of the cell

mechanical

19

What are the two types of metabolic processes?

Catabolism and Anabolism

20

Made from Ribose sugar (RNA sugar) and the nitrogen base Adenine.
Has 3 negative phosphates linked together which makes it highly unstable like a “compressed spring”. Unstable, means it has the capacity do perform work remember.
ATP converting to ADP gives off energy; ADP being converted to ATP requires energy.(The energy needed to make this bond comes from the “free” e in our food as it is broken down.)(ADP is recycled back to ATP.)

ATP (Adenine Tri-phosphate)

21

The attaching of an unstable phosphorus ion to another molecule to make it unstable and thereby able to perform work. (Take the phosphorus off and it quits working.)

phosphorylation

22

These molecules are Biological Catalysts.
(Proteins that speed up and control the rate of a chemical reaction.)

enzymes

23

Are enzymes recycled or consumed by reactions?

recycled

24

______ are selective in what they will work with. We used to say they had a “lock and key fit” (old term); we now say it “fits like a glove or has an induced fit”. (new term)
This is like putting on a latex glove… it stretches to conform to the shape of your hand.

Enzymes

25

names usually end with “ase”.

enzymes

26

This refers to the Free E used to start a chemical reaction in motion. (Essentially is the energy for getting the molecules moving and positioned so that it is possible to combine or be torn apart.)

Free E of Activation

27

The energy of _______ is lowered by the action of enzymes. (Enzymes reduce by grabbing the molecule and positioning it correctly… we don’t have to wait for nature to do it.)
Enzymes also replace the need for heat in most chemical reactions (remember heat can make molecules move faster) so that organisms don’t burn up during metabolism.

activation

28

This refers to the molecule that is being affected by the enzyme. (What the enzyme is grabbing and working on.)

substrate

29

This refers to the location where the chemical reaction(s) is taking place between the enzyme and substrate.

active site

30

The relationship between an enzyme and substrate is an Induced Fit , which creates the _______-_________ _________. (Complex meaning “more than one piece in the unit”.)

Enzyme-Substrate Complex

31

The two parts of an Enzyme-Substrate Complex are mainly held together by weak ________ bonds

hydrogen

32

Environmental factors that can affect enzymes ability to work optimally. (3)

Temperature – freeze/cold (cold things don’t move quickly) or Heat causing it to Denature (“unfold”).
pH of the environment
Salt concentrations

33

The Optimal Conditions for most human enzymes

98.6˚F (35 - 40⁰C)
pH usually between 7.2 and 7.6 (The human body’s pH of blood is an average of 7.4.)
Remember, this is an unstable (dynamic) environment. There is an upper limit and a lower limit for enzymes. Beyond the limits, bad things begin to happen. So it is basically, trying to stay between the limits. The limits of “life”.

34

The name implies that these molecules negatively affect an enzymes ability to work optimally. These slow down or stop the rate of the chemical reaction.

inhibitors

35

two types of inhibitors

competitive, non-competive

36

These molecules compete for the active site. (This is because of similar shape.)
These molecules slow down the reaction rate. (These molecules will be removed.)

competitive (inhibitors)

37

These molecules attach somewhere other than the active site causing the shape of the active site to change so the substrate can’t fit into it.
a. These molecules cause the reaction to stop completely

non-competitive (inhibitors)

38

A product in excess shuts down the reaction that is taking place at an earlier point in the pathway.
Prevents “waste” of precious materials and energy by not making more of what is not needed at that time.

Feedback inhibition