Topic 3- Haemoglobin

Question 1

What type of molecule is haemoglobin?

Answer 1

A protein

Question 1

What structure does haemoglobin have?

Answer 1

Quaternary- multiple polypeptide chains bonded together

Question 2

What is haemoglobin called when oxygen is bound?

Answer 2

Oxyhaemoglobin

Question 3

What is haem group?

Answer 3

An atom of iron enclosed in a ring structure

Question 4

What is the function of iron in the haem group?

Answer 4

To act as a magnet for oxygen (to form haemoglobin)

Question 5

What is haemoglobins?

Answer 5

A group of similar structures that occur in a very wide range of different animals

Question 6

What is the function of haemoglobin?

Answer 6

To carry oxygen around the body

Question 7

When do haemoglobin molecules combine with oxygen?

Answer 7

When oxygen is present in high concentrations (alveoli in the lungs)

Question 8

When is the process of oxyhaemoglobin reverse?

Answer 8

When the concentration of oxygen is low (in respiring tissue)

Question 9

Define affinity

Answer 9

how readily haemoglobin acquires oxygen molecules

Question 10

Define loading

Answer 10

haemoglobin acquires oxygen molecules

Question 11

What is partial pressure?

Answer 11

The pressure exerted by a speciic gas in a mixture of other gases

Question 12

What is the measurement of oxygen concentration?

Answer 12

po2

Question 13

Define saturation

Answer 13

The extent to which haemoglobin is loaded

Question 14

What is unloading?

Answer 14

as haemoglobin releases oxygen molecules

Question 15

What does an oxygen dissociation curve show?

Answer 15

The degree of haemoglobin saturation with oxygen plotted against different values of partial pressure of oxygen

Question 16

Why does haemoglobin have cooperative bonding?

Answer 16

The haemoglobin changes shape when the 1st oxygen binds which makes it easier for further oxygens to bind

Question 17

Where is haemoglobin found?

Answer 17

In red blood cells in vertebrates, earthworms, star fish, some insects, some plants and bacteria

Question 18

What gives haemoglobin its read colour?

Answer 18

The haem group

Question 19

How many oxygen molecules can be carried by one molecule of haemoglobin

Answer 19

4

Question 20

The greater the 1.—- of dissolved oxygen in cells, the higher the partial pressure

Answer 20

1. concentration

Question 21

As PO2 increases, haemoglobins 1—- for oxygen also increases

Answer 21

1.Affinity

Question 22

Where does oxygen enter the blood capillaries

Answer 22

The alveoli in the lungs

Question 23

Explain what happens during loading

Answer 23

-Alveoli have a high PO2 so oxygen loads onto haemoglobin to form oxyhaemoglobin
-When cells respire they use up oxygen which lowers the PO2
-Red blood cells deliver oxyhaemoglobin to respiring tissues where it unloads its oxygen
-The haemoglobin then returns to the lungs to pick up ore oxygen

Question 24

Does pCO2 effect oxygen unloading?

Answer 24

Yes as haemoglobin gives up oxyegn more easily at a high pCO2

Question 25

Why does pC02 increase when cells are respiring?

Answer 25

Respiring cells produce CO2

Question 26

what is the bohr effect?

Answer 26

-When the dissociation curve shifts right -The rate of oxygen of oxygen unloading increases -The saturation of blood is lower

Question 27

Give some examples of environments with a low oxygen concentration

Answer 27

-Underground -At high altitudes -Close to the seabeds

Question 28

What adaptations do animals that live in low oxygen environments have?

Answer 28

-Higher affinity because it has to be very good at loading any available oxygen -Dissociation curve is left of a human