Blood

Question 1

Function of red and yellow bone marrow

Answer 1

red forms blood cells
yellow is mainly stored energy as fat

Question 2

functions of blood

Answer 2

gaseous exchange
transport of nutrients, antibodies, hormones, water, metabolic waste

Question 3

blood components when centrifuged
what makes each up

Answer 3

plasma (55%) - water, proteins, electrolytes, gases
buffy coat (1%) - platelets, WBCs
haematocrit (45%) - RBCs

Question 4

why are RBCs biconcave

Answer 4

disc shape facilitates gaseous exchange
more haemoglobin is closer to the plasma membrane

Question 5

haemoglobin consists of
how many oxygen molecules can it carry

Answer 5

four polypeptide chains complexed with haem group
4 (one per haem group)

Question 6

life cycle of RBCs

Answer 6

erythropoiesis starts in the bone marrow
erythrocytes are released and circulate for 120 days
spleen and liver macrophages break down old erythrocytes releasing bilirubin, iron, AAs
liver processes bilirubin into bile
small intestine excretes in faeces
kidney excretes bile in urine and releases EPO

Question 7

antibodies present in A, B, AB and O blood groups

Answer 7

A: anti-B antibodies
B: anti-A antibodies
AB: no antibodies
O: anti-A antibodies
anti-B antibodies

Question 8

anaemia manifestations

Answer 8

insufficient Hb is insufficient within RBCs
reduced number of RBCs

Question 9

sickle cell anaemia cause
RBC features

Answer 9

autosomal recessive single point mutation in beta globin gene

sickle shaped
more rigid and do not enter finer capillaries
fragile and break down easily

Question 10

types of granulocytes
types of agranulocytes

Answer 10

granulocytes: neutrophil, eosinophil, basophil

agranulocytes: lymphocytes, monocytes

Question 11

what are azurophillic granules

Answer 11

large lysosomes of neutrophils

Question 12

nuclei of immune cells

Answer 12

neutrophils: polymorphonuclear
eosinophils: bilobed
basophils: bilobed
lymphocytes: round densely stained
monocytes: horseshoe (kidney) shaped

Question 13

what do eosinophil granules contain

Answer 13

peroxidase, histamine, arylsulfatase, other hydrolytic enzymes

Question 14

what do basophil granules contain

Answer 14

hydrolytic enzyme, histamine, heparin sulfate and slow reacting substance of anaphylaxis

Question 15

types of T-lymphocytes and their role

Answer 15

cytotoxic T-cells: recognise and kill
helper T-cells release factors to activate B-cells, CTLs and macrophages
suppressor T-cells: supress activity of B-lymphocytes and immune response

Question 16

what are precursors to macrophages

Answer 16

monocytes

Question 17

precursors to platelets

Answer 17

cytoplasm of megakaryocytes

Question 18

how are megakaryocytes formed and how is it different to other cells

Answer 18

endomitosis
DNA replication and karyokinesis same as mitosis but no cytokinesis

Question 19

what are plasma lipoproteins
function
two main types

Answer 19

soluble complex aggregates of lipids with specialised proteins
deliver insoluble lipids from the tissues
HDLs: good cholesterol
LDLs: bad cholesterol

Question 20

haematopoietic stem cells
common myeloid progenitor
common lymphoid progenitor

Answer 20

haematopoietic stem cells: give rise to CMPs and CLPs
common myeloid progenitor: give rise to RBCs, platelets, granulocytes and monocytes
common lymphoid progenitor: give rise to T and B lymphocytes