Muscle, Bone and Skin

Question 1

true or false - skeletal muscle is a striated, involuntary muscle

Answer 1

false - it is a striated, voluntary muscle

Question 2

what is a tendon

Answer 2

it is a connective tissue that connects muscle to bone

Question 3

what is the smallest functional unit of the contractile apparatus

Answer 3

sarcomere

Question 4

what are the Z and M line, A and I band, and H zone

Answer 4

Z line = separates one sarcomere from the next ; where the actin filaments attach
I band = only contains actin
H zone = only contains myosin
A band = where myosin and actin overlap
M line = midline of the myosin fibres

Question 5

how is a neuromuscular junction formed

Answer 5

when a motor neuron attaches to a muscle cell at a motor end plate

Question 6

what is a motor end plate

Answer 6

a highly excitable muscle

Question 7

what is the importance of T tubules

Answer 7

help control the uniform contraction of the muscle by allowing the action potential to spread through the muscle cell more quickly`

Question 8

explain the sliding filament model

Answer 8

• myosin heads are in a high energy state with a phosphate and ADP attached
• actin is protected by tropomyosin
• Calcium increases as there is a somatic nervous input and with calcium, the troponin pulls the tropomyosin away from the actin so that the myosin can bind
• the attachment between actin and myosin are called cross bridges
• once binded, ADP and phosphate are released, therefore the myosin is in a low energy state
• an ATP is produced and is attached to the myosin and is no longer bonded to the actin active site
• ATP is then split into ADP and phosphate, thus the myosin is again in a high energy state

Question 9

when does oxygen debt occur

Answer 9

after exercise when we need to metabolize the extra lactic acid produced

Question 10

true or false type 1 fibres carry a lot of myoglobin

Answer 10

true

Question 11

which type of fibre has as the bigger advantage and why

Answer 11

type 1 fibres are slower to get fatigued so they can be employed for long periods of time. Since there is a large amount of myoglobin, there is also alot of ATP to help the fibres operate for a long time

Question 12

what is the difference between type 2 A and B fibres

Answer 12

type 2 A contains myoglobin and has a fast contractile velocity and is resistant to fatigue
type 2 B contains glycogen and has an even faster contractile velocity but gets tired very easily

Question 13

what kind of muscle is the heart composed of

Answer 13

striated and involuntary cardiac muscle

Question 14

what kind of muscle are the internal organs and blood vessels composed of

Answer 14

smooth and involuntary muscle

Question 15

what is the most common type of smooth muscle

Answer 15

single unit smooth muscle

Question 16

what do osteoprogenitor cells differentiate into

Answer 16

osteoblasts

Question 17

are osteocytes capable of mitosis

Answer 17

no, they are incapable

Question 18

what is the function of osteoblasts

Answer 18

they secrete collagen and organic compounds, while this occurs they are also enveloped by the matrix. they then differentiate into osteocytes

Question 19

what is the function of osteocytes

Answer 19

they exchange nutrients and wastes with the blood

Question 20

are osteoblasts capable of mitosis

Answer 20

no, they are incapable

Question 21

true or false - spongy bone contains red bone marrow

Answer 21

true

Question 22

how is endocrine control involved in the remodelling of the bone

Answer 22

the regulation of the calcium levels in the blood is done by the parathyroid hormone. High levels of this hormone signal the osteoclasts to break down the bone so the calcium can be released into blood.

Question 23

what should you think when you see CA2+

Answer 23

muscle contractions and storage in bone

Question 24

what are some examples of long bones

Answer 24

finger, toe, leg and arm

Question 25

what are some examples of short bones

Answer 25

ankle and wrist

Question 26

what are some examples of flat bones

Answer 26

skull, ribs and shoulder blades

Question 27

what are some examples of irregular bones

Answer 27

ossicles

Question 28

what is a fibrous joint and give an example

Answer 28

between two bones with fibrous connective tissue to prevent much movement. Example : between teeth and mandible

Question 29

what is a cartilaginous joint and give an example

Answer 29

occurs between two bones connected with cartilage, allowing a little bit of movement. Example : ribs and sternum

Question 30

what is a synovial joint and given an example

Answer 30

two bones are separated by a capsule of synovial fluid, which acts as lubrication for the cartilage. Example : shoulder and knee

Question 31

what are the 7 functions of the skin

Answer 31

thermoregulation, protection, environment input, immunity, blood reservoir, vitamin D production, protecting against dehydration (osmoregulation)

Question 32

what is the difference between vasodilation and vasoconstriction

Answer 32

vasodilation allows for more heat loss by directing more blood to the surface capillaries vasoconstriction allows for less heat loss by preventing blood to go to the capillaries

Question 33

what kind of cells does majority of the epidermis layer of the skin contain

Answer 33

keratinocytes

Question 34

true or false - Merkel cells function in the sensation of taste

Answer 34

false - they function in the sensation of touch

Question 35

which sweat gland is found on the skin's surface and which is found in the dermis

Answer 35

``` eccrine = on surface apocrine = in dermis ```