Anatomy of Muscular Tissue

Question 1

what are the three types of muscular tissue?

Answer 1

• skeletal muscle
• cardiac muscle
• smooth muscle (visceral muscle)

Question 2

briefly describe skeletal muscle.

Answer 2

• it is a VOLUNTARY MUSCLE
• found within our SKELETON
• helps MOVE BONES
• is MULTI-NUCLEATED & STRIATED

Question 3

briefly describe cardiac muscle.

Answer 3

• it is an INVOLUNTARY MUSCLE
• found within our heart
• helps PUMP BLOOD/never stops contraction
• is UNI-NUCLEATED, STRIATED, also has INTERCALATED DISCS

Question 4

briefly describe visceral (smooth) muscle

Answer 4

• this is an INVOLUNTARY MUSCLE
• found within VARIOUS ORGANS
• varying functions: peristalsis etc…
• is UNI-NUCLEATED/ NO STRIATIONS

Question 5

what are the special characteristics of muscle tissue?

Answer 5

• excitability:
  the ability to receive & respond to stimuli
• contractibility:
  ability to shorten forcibly when stimulated
• extensibility:
  STRETCH
• elasticity:
  skill to recoil to resist length

Question 6

what are the muscle functions? what are the SKELETAL muscle functions?

Answer 6

• movement of the bones and fluid
• posture & body position
• regulates orifices
• stabilizes joints/supports soft tissue
• heat generation
• protection

Question 7

epimysium

Answer 7

dense irregular connective tissue surrounding the entire muscle; this is the most OUTERMOST COVERING

Question 8

perimysium

Answer 8

fibrous connective tissue that surrounds the FASCICLES; group of muscle fibers

Question 9

endomysium

Answer 9

fine areolar connective tissue that surrounds each MUSCLE FIBER/MUSCLE CELL

Question 10

sarcolemma

Answer 10

known as the “plasma membrane” for the muscle fibers

Question 11

myofibrils

Answer 11

also known as the “organelles”
- made up of myofilaments

Question 12

myofilaments

Answer 12

lined up to make up sarcomeres
- actin
- myosin

Question 13

sarcomere

Answer 13

smallest contractile unit of muscle fibers; made up of contractile proteins

Question 14

I bands

Answer 14

• this is our THIN and LIGHT BAND
• one I band to another: equivalent to one sarcomere
• stores ACTIN

Question 15

M line

Answer 15

this is the middle line of the sarcomere; divides the protein medially

Question 16

H zone

Answer 16

the no cross-boundary of other myofilaments/no crossing over only MYOSIN

Question 17

z discs/z lines

Answer 17

these are within our I bands; mark the middle line of I bands

Question 18

A bands

Answer 18

made up of actin and myosin (A & I bands) - has sections of overlap

Question 19

muscle

Answer 19

type of tissue that PERFORMS PHYSICAL WORK
1. helps GENERATE FORCE
2. causes MOTION

Question 20

muscle tissue

Answer 20

• CONTRACTILE:
  responsible for ACTIVE MOVEMENT of ORGANS/STRUCTURES
• EXCITABLE:
  uses ELECTRICAL SIGNALS to make CONTRACTIONS

Question 21

tendons

Answer 21

where the MUSCLES CONNECT TO BONE
- where all THREE CONNECTIVE LAYERS (epimysium, perimysium, endomysium) merge

Question 22

ligaments

Answer 22

connects BONE to BONE

Question 23

what are the PROTEIN COMPONENTS of a MYOFIBRIL?

Answer 23

• ACTIN:
  our THIN FILAMENT (made from G-actin molecules)
• MYOSIN:
  our THICK FILAMENT (myosin units - G-actin is the BINDING SITE for MYOSIN HEAD)
• TITIN:
  the “spring”; LARGEST PROTEIN - gives the “recoil” after contraction & STABILIZES the MYOSIN
• NEBULIN:
  helps ALIGN the ACTIN in its COIL FORM ALONG THE SARCOMERE