Lecture 15- Bone, Bone Marrow And Blood Vessels

Question 1

5 types of bones

Answer 1

Long bones- longer than they are wide. For support+ facilitating movement e.g femur, humorus, metacarpals
Short bones- length+ width same. Wrist and ankle joints. Provide stability
Flat bones- Flat. Found in skull, sternum, ribs. Protect organs
Irregular bones-Varying shapes. Vertebrae. Protect organs.
Sesamoid bones- Small sesame shaped bones. In the patella. Protect tendons

Question 2

2 types of bone

Answer 2

Cancellous bone- Spongy bone with trabeculae

Compact bone- Outer shell of bones. Strong

Question 3

Bone marrow

Answer 3

Red marrow- Rich blood supply, haemopoiesis

Yellow marrow- Poor blood supply, rich in adipocytes, differentiate into red marrow. Shock absorber aswell

Question 4

Importance of sinusoids

Answer 4

Type of capillary

Incomplete basement membrane+ intracellular gaps allowing molecules to pass through

Question 5

How do maturing cells bone?

Answer 5

Through the sinusoids

Question 6

Arteries

Answer 6

• Carry oxygenated blood away from the heart to the rest of the body.
• Pulmonary arteries- blood from lunges to heart.

Question 7

Structure of arteries

Answer 7

Tunica Intima: Endothelium
Tunica media: Smooth muscle and elastic fibres
Tunica Externa: Strong outer collagen and elastin fibres

Question 8

Difference between ARTERIES AND vEIN

Answer 8

SMALLER LUMEN, THICKER TUNICA MEDIA (SMOOTH MUSCLE), to withstand higher BP
Vein have valves

Question 9

4 types of Vein

Answer 9

Pulmonary- Oxygenated blood from the lungs to the heart
Systemic- Deoxygenated blood- rest of the body to right atrium
Superficial- Close to the skin
Deep- Located between tissue and near a corresponding artery

Question 10

Capillaries

Answer 10

From arteries to arteriolar to capillary bed.
Capillary bed one cell thick, fluid exchange occurs to body tissues
HAVE pre-capillary Sphincters (smooth muscle cell) that control contraction
Histamine opens capillary vessels

Question 11

Collateral blood vessels

Answer 11

1) Provide an alternate path for arterial blood flow

Question 12

Vasculogenesis

Answer 12

Formation of new blood vessels from precursor angioblasts

VEGF produced by endoderm, generates a cluster of cells+ creates endothelial cells of a newly developed blood cell

Question 13

Angiogenesis

Answer 13

Formation of more blood vessels from already
FGF produced from MSC
Endothelial lining grows away and smooth muscle move out of way in response to stimulus.
Formation of new blood vessels

Question 14

The pericyte

Answer 14

Wraps around capillaries and maintains tight capillaries and prevents endothelial cell proliferation