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Flashcards in Chapter 8 Deck (42)
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1
Q

Metabolism

A

Sum of all chemical reactions occurring in an organism

2
Q

Metabolic pathway

A

Begins with a specific molecule and ends with a product. Each step is catalyze by a specific enzyme

3
Q

Catabolic pathways

A

Release energy. Break down complex molecules into simpler compounds

4
Q

Anabolic pathways

A

Consume energy to build complex molecules from simpler ones. Ex: synthesis of protein from amino acids

5
Q

Energy

A

The capacity to cause change. Exists in various forms, some of which can perform work

6
Q

Kinetic energy

A

Energy associated with motion

7
Q

Potential energy

A

Energy that matter possesses because of its location or structure

8
Q

First law of thermodynamics

A

Energy can be transferred and transformed but it cannot be created or destroyed. Sunlight is converted into chemical energy by photosynthesis

9
Q

During every energy transfer/transformation…

A

Some energy is unusable and is often lost as heat

10
Q

Second law of thermodynamics

A

Every energy transfer/transformation increases the entropy of the universe

11
Q

Entropy

A

A measure of molecular disorder or randomness

12
Q

Spontaneous processes

A

Occur without energy input and can happen quickly or slowly. For a process to occur without energy input, it must increase the entropy of the universe

13
Q

Disorder

A

Happens spontaneously

14
Q

Organization

A

Requires energy

15
Q

Order and disorder

A

Cells create ordered structures from less ordered materials. Organisms also replace ordered forms of matter and energy with less ordered forms

16
Q

Free energy

A

The energy available to work. The symbol G

17
Q

Enthalpy

A

Energy contained in a molecules chemical bonds

18
Q

Delta G is positive

A

When products contain more free energy than reactants

19
Q

Delta G is negative

A

When reactants contain more free energy than products

20
Q

Endergonic reaction

A

A reaction requiring an input of energy (not spontaneous) Delta G is positive

21
Q

Exergonic reaction

A

A reaction that releases free energy (spontaneous). Delta G is negative

22
Q

ATP is composed of

A

Ribose (a sugar), adenine (a nitrogenous base), and three phosphate groups

23
Q

Hydrolysis of ATP

A

ATP is turned into ADP by hydrolysis.

24
Q

Activation energy

A

Extra energy needed to get a reaction started.

25
Q

Catalysts

A

Substances that lower activation energy of a reaction. Cannot make an endergonic reaction spontaneous.

26
Q

Enzyme

A

Biological catalyst. Most enzymes are proteins

27
Q

Substrate

A

The reactant that an enzyme acts on is called the enzymes substrate

28
Q

Enzyme-substrate complex

A

The enzyme binds to its substrate, forming an enzyme-substrate complex

29
Q

Active site

A

The region on the enzyme where the substrate binds

30
Q

Induced fit

A

Induced fit of a substrate brings chemical groups of the active sit into positions that enhance their ability to catalyze the reaction

31
Q

Cofactors

A

Usually metal ions, found in the active site participating in catalysts (Zn, Mn, Mo)

32
Q

Coenzymes

A

Organic molecule cofactors which include vitamins

33
Q

Inhibitor

A

Substance that binds to enzyme and decreases it’s activity

34
Q

Competitive inhibitors

A

Bind to the active site of an enzyme, competing with the substrate

35
Q

Noncompetitive inhibitors

A

Bind to another part of an enzyme, causing the enzyme to change shape and making the active site less effective

36
Q

Allosteric enzymes

A

Exist in either an active or inactive state

37
Q

Allosteric site

A

Allosteric enzymes possess an allosteric site where molecules other than the substrate bind

38
Q

Allosteric inhibitors

A

Bind to the allosteric site to inactivate the enzyme

39
Q

Allosteric activators

A

Bind to the allosteric site to activate the enzyme

40
Q

Biochemical pathways

A

A series of reactions in which the product of one reaction becomes the substrate for the next reaction

41
Q

Feedback inhibition

A

The end product of a metabolic pathway shuts down the pathway

42
Q

Feedback inhibition prevents a cell

A

From wasting chemical resources by synthesizing more product than is needed