Brainscape's Knowledge GenomeTM

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


See full index

Y12 AS Biology > Digestion and absorption > Flashcards

Digestion and absorption Flashcards

1
Q

Through what reaction are biological molecules broken down?

A

Hydrolysis

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

What is amylase?

A

Digestive enzyme

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

What does amylase do?

A

Catalyses the breakdown of starch

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

Where is amylase produced?

A

Salivary glands

Pancreas

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

Where is amylase released into?

A

Mouth

Small intestine

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

What is starch broken down into?

A

Glucose molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are membrane-bound disaccharidases?

A

Enzymes attached to the cell membranes of epithelial cells lining the ileum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What do membrane-bound disaccharidases break down?

A

Disaccharides into monosaccarides

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

What are sucrase, maltase and lactase examples of?

A

Membrane bound disaccharidases

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

What reaction does sucrase catalyse?

A

Breakdown of sucrose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is sucrose broken down into?

A

Glucose and fructose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What reaction does maltase catalyse?

A

Breakdown of maltose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is maltose broken down into?

A

Glucose and glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do lipase enzymes catalyse the breakdown of?

A

Lipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are lipids broken down into?

A

Monoglycerides and fatty acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What bonds in lipids are hydrolysed?

A

Ester

17
Q

Where are lipase enzymes mainly made?

A

Pancreas

18
Q

Where are lipase enzymes secreted into?

A

Small intestine

19
Q

Where are bile salts produced?

A

Liver

20
Q

What do bile salts do?

A

Emulsify lipids

21
Q

How does the work of bile salts benefit digestion of lipids?

A

They increase the surface area thats available for the lipase enzymes to work on

22
Q

What is a micelle?

A

Tiny structures of bile salts with attached monoglycerides and fatty acids

23
Q

What enzymes break down proteins?

A

Peptidases

24
Q

What are the three types of peptidases?

A

Endopeptidases
Exopeptidases
Dipeptidases

25
Q

What bonds in proteins are hydrolysed?

A

Peptide bonds

26
Q

Where on a protein do endopeptidases work to hydrolyse the bonds?

A

in the middle of the polypeptide chain

27
Q

Where on a protein do exopeptidases work to hydrolyse the bonds?

A

At the end of the polypeptide chain

28
Q

What do dipeptidases only work on?

A

Dipeptide

29
Q

What is a dipeptide?

A

Two amino acids in a chain joined by a peptide bond

30
Q

How is it beneficial to have all three peptidases working together during protein digestion?

A

The endopeptidases create more ends/more surface area for the exopeptidases and dipeptidases to work on, which makes the process faster

31
Q

How are glucose and galactose absorbed?

A

By active transport with sodium ions via a co-tranporter protein

32
Q

How is fructose absorbed?

A

Via facillitated diffusion through a different transporter protein

33
Q

How are monoglycerides and fatty acids absorbed?

A

The micelles move them towards the epithelium and then break up to release them so they can be absorbed

34
Q

How are amino acids absorbed?

A

Sodium ions are actively transported out of the cell into the epithelium and when they diffuse back through a sodium-dependent transporter protein, they bring the amino acids with them

35
Q

Where is maltase produced?

A

Small intestine

36
Q

Describe the role of enzymes of the digestive system in the complete breakdown of starch (5 marks)

A

1) Hydrolysis of glycosidic bonds
2) by amylase
3) produces maltose which is a disaccharide
4) maltase breaks down maltose by hydrolysing the glycosidic bonds
5) into two molecules of glucose

37
Q

Suggest and explain why the combined actions of endopeptidases and exopeptidase are more efficient than exopeptidases on their own (2 marks)

A
  • It’s faster

- more ends are made to increase surface area for exopeptidases to work on

38
Q

Give an advantage of lactase and other digestive enzymes being located in the plasma membranes of cells lining the small intestine rather than being secreted into the lumen of the small intestine (1 mark)

A

Membrane bound so they aren’t lost through faeces

39
Q

The concentration of glucose in the blood rises after eating a meal containing carbohydrates. The rise is slower if the carbohydrate is starch rather than sucrose. Why? (3 marks)

A

1) Starch digested by amylase to maltose
2) Maltose digested by maltase into glucose
3) Sucrose is digested by sucrase into glucose , only a single step

Y12 AS Biology (57 decks)

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