3B - More Exchange and Transport Systems Flashcards Preview

Year 1 Biology > 3B - More Exchange and Transport Systems > Flashcards

Flashcards in 3B - More Exchange and Transport Systems Deck (48):
1

What type of reaction is used in digestion

Hydrolysis

2

Describe the digestion of carbohydrates

Amylase produced in the salivary glands breaks down starch in the mouth into maltose
Amylase produced in the pancreas is also released into the ileum.
Maltase, a membrane bound disaccharide breaks maltose down into glucose.
Glucose is absorbed through co-transport

3

Describe the digestion of lipids

The pancreas produces lipases which catalyse the break down of lipids into monoglycerides by hydrolysing the ester bonds.
Bile salts made in the liver emulsify the lipids to increase surface area.
The monoglycerides and fatty acids stick to the bile salts forming micelles.

4

For each of the following disaccharide name it disaccharidase and the monosaccharaides it is composed of:
a)sucrose
b)maltose
c)lactose

a) lactase => glucose + fructose
b) maltase => glucose + glucose
c) lactase => glucose + galactose

5

Describe the digestion of polypeptides

Peptides are broken down by peptidases which hydrolyse their peptide bonds between the amino acids.

6

What are the differences between endo and exo peptideases?

Endo: - hydrolyse bonds with in a polypeptide to form two shorter polypeptides
Exo: - hydrolyse the peptide bond at the end of a chain to make a polypeptide and an amino acid

7

What is a dipeptidase?

Exopeptidases that work specifically on dipeptides to break them into two amino acids

8

How are the following monosaccharaides absorbed?
a) Glucose
b) Fructose
c) Galactose

a) Active transport with sodium ions via a co-transporter
b) Facilitated diffusion using a transporter protein
c) Active transport with sodium ions via a co-transporter

9

How are monoglycerides and fatty acids absorbed?

They diffuse across the epithelial membrane as they are lipid soluble.

10

Where is haemoglobin found in humans?

Red blood cells

11

What is Hb?

Haemoglobin

12

Describe the structure of haemoglobin.

A large protein with a quaternary structure which is composed of 4 polypeptide chains. Each chain has a haem group containing iron. Each molecule of Hb can carry 4 O2 molecules.

13

What do oxygen and haemoglobin form?

Oxyhaemoglobin

14

What is association?

When an oxygen molecule joins to a haemoglobin.

15

What is dissociation?

When an oxygen molecule leaves a haemoglobin

16

What is affinity for oxygen.

The tendency haemoglobin has to bind with oxygen.

17

pO2

Partial pressure of oxygen - a measure of oxygen concentration

18

As partial pressure increases haemoglobins affinity for oxygen....

Increases. This means in areas with high oxygen concentrations oxygen will bind to haemoglobin.

19

What does a dissociation curve show?

How saturated haemoglobin is with oxygen at a given partial pressure.

20

How does the saturation of haemoglobin affects its affinity?

The first O2 molecule is hard to bind to the haemoglobin as the binding site is hard to reach. Once this oxygen has bound to the haemoglobin it changes the shape of the molecule so the 2nd and 3rd O2 molecules are easier to bind.

21

pCO2

Partial pressure of CO2

22

How does increasing pCO2 change affinity for oxygen

Decreases it

23

Coronary Heart Disease (C.H.D)

A cardiovascular disease which occurs when the coronary arteries have restricted blood flow due to atheromas.

24

Coronary Arteries

Supply the heart muscle with glucose and oxygen.

25

Atheroma

Fatty deposits that form in the wall of an artery

26

Fatty streak

White blood cells what have taken up L.D.L's

27

Atheromatus Plaque

Deposits of cholesterol, fibres and dead muscle cells within the artery wall.

28

Thrombus

A blood clot

29

Endothelium

Lining of the blood vessel

30

Thrombosis

A reduction in blood flow that has deprived an area of oxygen and glucose.

31

Aneurysm

A blood filled swelling formed at a weakened point in an artery wall

32

Haemorrhage

Loss of blood

33

Myocardial Infarction

Heart attack - a reduced blood flow supplying the heart muscle

34

Carbon monoxide

Reduces the O2 carried by red blood cells

35

Angina

Chest pain

36

Nicotine

Makes red blood cells sticky

37

H.D.L's

high density lipoproteins - removes cholesterol from the tissue

38

L.D.L's

low density lipoproteins - transports cholesterol to tissues.

39

How do valves in the heart work

Higher pressure behind the valve forces it open. This increases the pressure in front of the valve which closes the valve.

40

What do valves do?

Prevent backflow of blood

41

What are semi-lunar valves

Valves that link the ventricles to the pulmonary artery and aorta

42

What are atrioventricular valves

Valves that link the ventricles and atria

43

What is the vena cava

A vein which bring deoxygenated blood from the body into the right atrium

44

What is the pulmonary artery

An artery which takes deoxygenated blood from the heart and to the lungs

45

What blood vessel takes oxygenated blood from the heart to the body

Aorta

46

What blood vessel take s oxygenated blood from the lungs to the heart

Pulmonary vein

47

Compare and explain the thickness of the walls of the atria and the ventricles.

The ventricles have thicker walls than the atria so then they are able to push the blood out of the heart where as the atria only have to push blood into the ventricles

48

What name is given to diseases associated with the heart

Cardiovascular