Blood

Question 1

Blood make up

~45%

Answer 1

Formed elements (red blood cells, white blood cells and platelets). Lots of types branch from whites.

Question 2

Separating Blood Layers

Bottom

Answer 2

Red cells

Question 3

Albumen

Answer 3

Found in the serum, and constitutes about 60% of the plasma proteins in humans. Maintains osmotic pressure.

Question 4

Erythrocytes

What are they?

Answer 4

Red blood cells

Question 5

Erythrocytes

Life span

Answer 5

About 4 months

Question 6

Proportions of white blood cells

Answer 6

Neutrophils 40-75%

Eosinophils 5%

Basophils 0.5%

Lymphocytes 20-50%

Monocytes 1-5%

Question 7

Leukocytes - Neutrophils

What are they?

Answer 7

Granulocytes

Question 8

Leukocytes - Eosinophils

Name comes from?

Answer 8

Comes from affiity for eosin dye. Also a granulocyte. Circulate for 8-12 hours then move into tissues where most eosinophils live.

Question 9

Basophils

What are they?

Answer 9

The rarest of the granulocytes

Many similarities to mast cells. Evidence for, but not confirmed, common lineage.

Question 10

Monocytes

Where are they found?

Answer 10

Bone marrow and blood

Question 11

Leukocytes - Lymphocytes

Granules

Answer 11

Not visible

Question 12

Platelets

What are they?

Answer 12

Formed element of the blood

Question 13

Development

Earliest erythrocyte formation

Answer 13

Outside embryo in the yolk sac

Question 14

Stem cells

Totipotent

Answer 14

Can form all cell types in the adult plus any extra embryonic tissue produced in development

Pluri, multi and committed progenitor cells can reproduce themselves.

Question 15

Reticulocyte

Answer 15

The phase just before a mature RBC. have granules of RNA in cytoplasm, maturing through a series of steps.

Question 16

Leukoycte Maturation

Within the bone marrow

Answer 16

Each type goes through a set of stereotypical steps

Question 17

Megakaryocytes

What are they?

What do they do?

Answer 17

Giant (30-100µm) cells found in bone marrow. Produce platelets (thousands)

Question 18

Bone marrow control

Hormone production

Answer 18

Many hormones and growth factors produced locally within bone marrow.

Question 19

Blood brain barrier

Induced by

Answer 19

Astrocytes - do not form the blood brain barrier

Question 20

Blood make up

~55%

Answer 20

~90% of this is water, rest is made up from Proteins and Nutrients, and salts.

Question 21

Separating Blood Layers

Next

Answer 21

White cells

Question 22

Separating Blood Layers

Top

Answer 22

Plasma (liquid) - Without clotting factors is called Serum.

Question 23

Erythrocytes

Size

Answer 23

7µm

Question 24

Erythrocytes

Are they cells?

Answer 24

No. No nuclei or organelles

Question 25

**_Erythrocytes_** Abilities

Answer 25

Able to deform and slip through small spaces. Pick up haemoglobin.

Question 26

**_Erythrocytes_** Reouleaux

Answer 26

Stacks of RBC's which may indicate disease

Question 27

**_Leukocytes - Neutrophils_** What is their job?

Answer 27

Circulate in an inactive state, but can enter tissue where they are highly motile phagocytes.

Question 28

**_Leukocytes - Neutrophils_** Life cycle

Answer 28

Abundant and short-lived

Question 29

**_Leukocytes - Eosinophils_** Function

Answer 29

Important in inducing and maintaining inflammation and fighting parasitic infections.

Question 30

**_Basophils_** Function

Answer 30

Act as effector cells in allergic reactions ## Footnote *Many similarities to mast cells. Evidence for, but not confirmed, common lineage.*

Question 31

**_Monocytes_** What do they do?

Answer 31

Precursors of tissue macrophages. Form the mononuclear phagocyte system.

Question 32

**_Monocytes_** Size

Answer 32

Largest in the blood.

Question 33

**_Leukocytes - Lymphocytes_** Classes

Answer 33

B cells and T cells

Question 34

**_Leukocytes - Lymphocytes_** Maturation

Answer 34

B cells in the bone marrow, T cells in the thymus.

Question 35

**_Leukocytes - Lymphocytes_** Functions

Answer 35

B cells give rise to antibody secreting plasma cells, while T cells form a complex set of cells which perform many defence functions.

Question 36

**_Platelets_** What size are they?

Answer 36

2µm

Question 37

**_Platelets_** What do they do?

Answer 37

Play a key role in haemostasis. In this they adhere to the site of damage, aggregate and degranulate. Activate fibrin production.

Question 38

**_Platelets_** Organelles

Answer 38

Good cytoskeleten. Mitochondria, ribosomes and sometimes golgi, but no nucleus.

Question 39

**_Development_** Second trimester

Answer 39

Liver is principal site of blood formtion

Question 40

**_Development_** Bone Marrow

Answer 40

Bone marrow start to make leukocytes then eventually erythrocytes. At birth almost all bones produce blood but by maturity only cerain bones continue.

Question 41

**_Stem cells_** Pluripotent

Answer 41

Can give rise to all functional cell types ## Footnote *Pluri, multi and committed progenitor cells can reproduce themselves.*

Question 42

**_Stem cells_** Multipotent

Answer 42

Can give rise to restricted set of cell types ## Footnote *Pluri, multi and committed progenitor cells can reproduce themselves.*

Question 43

**_Stem cells_** Committed progenitor cells

Answer 43

Can produce only one cell type. ## Footnote *Pluri, multi and committed progenitor cells can reproduce themselves.*

Question 44

**_Bone marrow control_** Locally produced

Answer 44

Locally produced promoters include colony stimulating factors.

Question 45

**_Bone marrow control_** Systemic factors

Answer 45

Systemic factors include interleukins.

Question 46

**_Bone marrow control_** Erythropoietin

Answer 46

Erythropoietin produced by kidney stimulating erythrocyte production.

Question 47

**_Bone marrow control_** Control of

Answer 47

Control of proliferation, differentiation and maturation.