bone, bone marrow, vessels and blood

Question 1

types of bone

Answer 1

long, short, flat, irregular and sesamoid

Question 2

long bones and example of where they are found

Answer 2

longer than they are wide, found in the femur - support body weight and aid movement

Question 3

short bone and example of where they are found

Answer 3

as long as they are wide, found in the wrist and ankle joints - provide stability

Question 4

flat bones and example of where they are found

Answer 4

they are somewhat flat in shape and are found in the skull, thoracic cage (ribs) and pelvis - protect internal organs and large area for muscle attachment

Question 5

irregular bones and example of where they are found

Answer 5

they don’t fit into any other category because they vary in shape. example is the spine - protect internal organs e.g vertebrae protect spinal chord

Question 6

sesamoid bones and example of where they are found

Answer 6

small round bones found at tendons e.g patella of the knee - protect tendons from stress and damage.

Question 7

what are the 2 types of bone found in a long bone

Answer 7

cancellous - spongy and filled with bone marrow in the middle
compact - external hard bone

Question 8

make up and function of red marrow

Answer 8

rich blood supply found in spongey bone, replenish red blood cells in blood

Question 9

make up and function of yellow marrow

Answer 9

full of adipocytes and poor blood supply. acts as shock absorber and energy source. can convert to red marrow

Question 10

structure of cancellous spongey bone

Answer 10

each trabeculum consists of many osteocytes in lamellae like rings on an old tree. osteoblasts and osteoclast are on the outside and are able to remodel them. draw picture

Question 11

how do mature cells leave the bone?

Answer 11

cells move into sinusoid capillaries which lead to the central marrow vein to take them out of bone.

Question 12

how do platelets leave the bone

Answer 12

a megakaryocytic will bind to the sinusoid cell wall and release platelets into the lumen

Question 13

what are the different types of vessel

Answer 13

continuous- no gaps
fenestrated- with fenestrations
sinusoid - an incomplete basement membrane

Question 14

pathway which the newly forms red blood cells take after leaving the bone marrow

Answer 14

venule to vein to larger vein to vena cava. takes them 2 days to be activated

Question 15

pathway which newly formed white blood cells take after leaving the bone marrow

Answer 15

same route as red blood cells but T cells need to be matured in the thymus. ( B cells were already matured in the bone marrow)

Question 16

what is microcirculation/ precapillary sphincters

Answer 16

located between arterioles and capillaries they can contract to prevent the flow of blood into the capillaries. Controls fluid exchange between capillaries and tissues outside capillary bed

Question 17

what is the structure of a vein

Answer 17

carries blood from body to the heart. 3 layer including:
1) tunica intima- endothelial cells
2)tunica media - elastic fibres and smooth muscle
3) tunica externa- elastic fibrous capsule
have large lumen, low pressure, run through large muscles and have valves to prevent back flow of blood

Question 18

where does the vena cava lead to and where does the blood flow after that

Answer 18

the right atrium of the heart. Right = deoxygenated. then goes to lungs via pulmonary artery and back to left atrium and then around the body

Question 19

types of veins

Answer 19

pulmonary- carry oxygenated blood to left atrium of heart
systematic - carry deoxygenated blood to heart
superficial- located near skins surface
deep- located deep near organs

Question 20

structure of an artery

Answer 20

carry oxygenated blood away from the heart

1) tunica intima - elastic lining and smooth endothelium
2) tunica media - smooth muscle and elastic fibres. Much thicker than veins
3) tunica externa - strong outside capsule with elastin and collagen so allows them to stretch but prevents over expansion

Question 21

artery vs vein

Answer 21

artery - thick walls, narrow lumen, no vales, lots of elastic and collagen to withstand pressure. High blood pressure resists back flow
vein - thin walls, wide lumen, valves to prevent back flow and wide lumen = less resistance for blood flow

Question 22

function of collateral blood vessels

Answer 22

provide protection for tissues that become compromised by providing an alternate pathway

Question 23

what is angiogenesis

Answer 23

production of new blood vessels from existing ones

Question 24

what is vasculogenesis

Answer 24

formation of new blood vessels

Question 25

what is a pericyte

Answer 25

found in capillaries and venules. prevents endothelial cell proliferation and maintains tight capillaries e.g blood barrier in brain