Transport of gases

Question 1

What is blood?

Answer 1

• Aqueous medium
• allows for gas exchange
• delivery of important molecules (eg. glucose and oxygen)

Question 2

why is blood considered a connective tissue?

Answer 2

• It connects the body systems, transports oxygen and nutrients to all the parts of the body, and removes waste products.

Question 3

Plasma is?

Answer 3

• 90% water
• straw-coloured fluid
• contains a range of dissolved materials

Question 4

what dissolved materials are in plasma?

Answer 4

• Hormones
• amino acids
• urea
• glucose
• carbon dioxide
• salt
• Plasma proteins

Question 5

what are the 3 types of blood cell?

Answer 5

1. Leucocytes (white blood cells)
2. Thrombocytes (platelets)
3. Erythrocytes (red blood cells)

Question 6

what 2 groups of immune cells can Leucocytes be divided into?

Answer 6

• Granulocytes
• Agranulocytes

Question 7

what are Granulocytes?

Answer 7

• have granular cytoplasm (lysosome)
• lobed nuclei (allows more flexibility)
• function: engulf pathogens by phagocytosis

Question 8

what are Agranulocytes?

Answer 8

• produce antibodies + antitoxins
• clear cytoplasm
• spherical nucleus

Question 9

what are Thrombocytes involved in?

Answer 9

Blood clotting
- 3-4 min to stop bleeding
- acts as a mesh

Question 10

what are the 3 features of Erythrocytes?

Answer 10

1. biconcave discs - gives large SA so more O2 can diffuse across the membrane
2. no nucleus (mammalian) - more room for haemoglobin, more O2 can be transported
3. flexible - so they can fit through narrow lumen of the capillaries

Question 11

what are Erythrocytes filled with?

Answer 11

Pigment Haemoglobin (Hb)

Question 12

What is haemoglobin?

Answer 12

• Globular Protein
• quaternary structure
• 4 folded polypeptide chains
• centre of each polypeptide is a haem group, contains iron
• each haem group is a binding site for 1 oxygen molecule

Question 13

What is the reaction between haemoglobin and oxygen?

Answer 13

Hb+40^2 –><– Hb4O^2

Question 14

Define Affinity

Answer 14

• the degree to which one molecule (Haemoglobin) is chemically attracted to another molecule (oxygen)

Question 15

define saturation

Answer 15

• the percentage of oxygen bound to Haemoglobin

Question 16

define Association/Loading

Answer 16

the uptake of oxygen by haemoglobin to form oxyhaemoglobin at the lungs

Question 17

define Dissociation/unloading

Answer 17

the release of oxygen at the respiring tissues to form haemoglobin