ANAT NOTES 10 PART 1

Question 1

muscles are both…

Answer 1

voluntary and involuntary

Question 2

skeletal muscle makes up

Answer 2

nearly half of the body’a mass and is 40% of body weight

Question 3

aponeurosis (dense connective tissue)

Answer 3

connects a muscle to underlying structures through a flat sheet or web

Question 4

how many skeletal muscles are there?

Answer 4

600

Question 5

3 categories of muscle

Answer 5

• skeletal
• cardiac
• smooth

Question 6

properties of muscle tissue

Answer 6

• contractility
• excitability
• extensibility
• elasticity

Question 7

Contractility

Answer 7

Myofilaments (actin and myosin) responsible for shortening (contracting) of muscle cells

Question 8

Excitability

Answer 8

Nerve signals excite muscle cells

Question 9

Extensibility

Answer 9

Smooth muscle is stretched by substances within that hollow organ

Question 10

Elasticity

Answer 10

Recoils after being stretched

Question 11

gross anatomy of a skeletal muscle

Answer 11

• epimysium
• perimysium
• endomysium

Question 12

origin

Answer 12

less movable muscle attachment

Question 13

insertion

Answer 13

more movable muscle attachment

Question 14

what are striations resulted from?

Answer 14

internal structure of myofibrils

Question 15

myofibrils

Answer 15

• are long rods with cytoplasm
• make up 80% of the cytoplasm
• long row of repeating segments called sarcomeres

Question 16

where does the nerve ending and muscle fiber meet?

Answer 16

neuromuscular junction

Question 17

terminal boutons (axon terminals)

Answer 17

• located at ends of axons

- store neurotransmitters

Question 18

muscular dystrophy

Answer 18

group of inherited muscle destroying disease causing the muscles to degenerate and atrophy

Question 19

what happens to the muscles affected by muscular dystrophy?

Answer 19

enlarge with fat and connective tissue