Muscle types/Structure

Question 1

myogenesis

Answer 1

the formation of muscle tissue during the development of an embryo

Question 2

myoblasts

Answer 2

a type of embryonic stem cell that gives rise to muscle cells

Question 3

differentiation

Answer 3

morphological modification of the cells to perform the assigned function

Question 4

3 main muscle tissue types

Answer 4

skeletal, smooth, cardiac

Question 5

muscle fibers are organized how

Answer 5

into bundles supplied by blood vessels and innervated by motor neurons

Question 6

what is skeletal muscle tissue composed of

Answer 6

long cells called muscle fibers that have a striated appearance

Question 7

how do skeletal muscles attach to and move bones

Answer 7

contracting and relaxing in response to voluntary messages from the NS

Question 8

6 functions of skeletal muscle tissue

Answer 8

produce body movement
maintain posture and body position
support soft tissue
guard body exits/entrances
maintain body temp
store nutrients

Question 9

epimysium

Answer 9

outer layer of connective tissue around a skeletal muscle

Question 10

perimysium

Answer 10

connective tissue that bundles skeletal muscle fibers into fascicles within a skeletal muscle

Question 11

endomysium

Answer 11

loose, well hydrated connective tissue covering each muscle fiber in a skeletal muscle

Question 12

fascicles

Answer 12

bundle of muscle fibers within a skeletal muscle

Question 13

myofibers

Answer 13

the muscle fiber, the skeletal muscle cell (make up the bundles of muscles -fascicle)

Question 14

myofibril

Answer 14

long cylindrical organelle that runs parallel within the muscle fiber and contain the sarcomeres

Question 15

sarcomere

Answer 15

longitudinally, repeating functional unit of skeletal muscle, with all of the contractile and associated proteins involved in contraction

Question 16

myosin

Answer 16

protein that makes up most of the thick cylindrical myofilament within a sarcomere muscle fiber

Question 17

Actin

Answer 17

protein that makes up most of the thin myofilaments in a sarcomere muscle fiber

Question 18

what are myofibrils composed off?

Answer 18

smaller structures called myofilaments (actin & myosin)

Question 19

what are the edible portions of mammals?

Answer 19

muscles, fat, bone, connective tissue and water

Question 20

meat does not include muscles that are found where

Answer 20

lips, snout, or ears

Question 21

meat science

Answer 21

study of all facets of the meat industry, beginning with animal production and ending with final preparation of meat for consumption

Question 22

what are the steps of muscle contraction? (9)

Answer 22

1. nerve impulses reach axon terminal
2. acetylcholine (Ach) is released into synapse
3. Ach crosses synapse & binds to receptors on sarcolemma
4. Ach causes change in membrane permeability: action potential is generated
5. calcium ions are released from the sarcoplasmic reticulum
6. Ca 2+ binds to regulatory proteins on actin, exposing binding sites for myosin
7. myosin heads bind to actin forming crossbridges
8. actin filaments pulled toward center of sarcomere
9. the sarcomere shortens and muscles contracts

Question 23

What happens when the action potential ends (after contraction)?

Answer 23

-calcium ions are reabsorbed into sarcoplasmic reticulum
-reg. proteins cover binding site on actin: myosin can no longer attach to form cross bridges
-muscle relaxes: returns to original length
-resting potential is restored