Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

bio topic 1 > enzymes > Flashcards

enzymes Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What is the function of an enzyme?

A

To speed up the rate of reaction by lowering the activation energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are enzymes? [2]

A

Biological catalysts
Proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a substrate?

A

The substance that the enzyme acts on

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is an active site?

A

The area of an enzyme where the complimentary substrate fits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is wrong with the Lock and Key model?

A

It is old and outdated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the Lock and Key model [3]

A
  • The active site is a fixed shape
  • complementary to one substrate only
  • after a successful collision an enzyme-substrate complex is formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the Induced Fit Model [4]

A
  • Before reaction, active site NOT completely COMPLIMENTARY to substrate
  • Active site alters structurally as substrate binds
  • enzyme-substrate complex forms
  • This stresses / distorts the bonds in a substrate leading to a reaction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What structural level are enzymes?

A

tertiary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a metabolic reaction?

A

reaction that occurs inside a living organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is Anabolism? [3]

A
  • Simple molecules become more complex
  • Uses energy
    e.g. photosynthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is Catabolism?

A
  • Complex molecules become simpler
  • Release energy
    e.g. respiration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does enzyme / substrate concentration affect the rate of reaction? [4]

A
  • As concentration increases rate of reaction increases
  • more successful collisions and enzyme-substrate complexes
  • At a certain point it plateaus
  • The enzyme / substrate concentration becomes the limiting factor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does a decreased temperature affect rate of reaction? [4]

A
  • Reactant molecules have a low kinetic energy
  • For enzyme-substrate complexes to form reactants must collide with a particular amount of force
  • Low kinetic energy results in fewer successful collisions
  • Decreasing rate of reaction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does an increased temperature affect rate of reaction? [9]

A
  • Kinetic energy increases
  • More successful collisions and enzyme-substrate complexes
  • Increased rate of reaction
  • Once the temperature increases above the optimum
  • Bonds within the enzyme begin to break
  • 3D structure of the enzyme including active site alters
  • substrate no longer complimentary to active site
  • enzyme denatured
  • rate of reaction decreases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does altered pH affect the rate of reaction? [4]

A
  • bonds break
  • tertiary structure of enzyme including active site structurally alters
  • fewer successful collisions and enzyme-substrate complexes as enzymes denatured
  • decreased rate of reaction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are inhibitors?

A

Prevents enzymes from working

17
Q

What are Competitive Inhibitors? [4]

A
  • Similar in shape to the substrate
  • competes for the active site
  • usually reversible
    e.g. methanol poisoning
18
Q

What are Non-Competitive Inhibitors? [5]

A
  • Bind to an area of the enzyme other than the active site (allosteric)
  • Causing the 3D structure of the enzyme, including active site, to alter
  • Enzyme-substrate complex can’t form
  • Often irreversible
    e.g. heavy metals : Mercury, lead, arsenic
19
Q

What are End-Product Inhibitors? [2]

A
  • As levels of end product increase the enzyme is inhibited
  • When levels of the end product decrease again the inhibition stops
20
Q

How is Starch digested? [2]

A
  • Starch hydrolysed to Maltose by amylase
  • Maltose hydrolysed to glucose by maltase
21
Q

How is Protein digested?

A
  • Intrinsic bonds within the Protein are broken and Proteins are hydrolysed into polypeptides by endopeptidases
  • terminal bonds within polypeptides are then broken and polypeptide hydrolysed into dipeptides by exopeptidase
  • peptide bonds between amino acids are broken and dipeptides are hydrolysed into amino acids by didpeptidase
22
Q

How are Lipids digested?

A
  • Lipids are emulsified by bile salts into emulsified Lipids
  • Emulsified Lipids are hydrolysed by lipase into fatty acids and glycerol

bio topic 1 (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions