Muscle Tissue And Skeletal Muscles - Tutorial 2

Question 1

Describe four functions of muscle tissue

Answer 1

• Produce movement
• Maintain posture and stabilise joints and body positions
• Storing and moving substances in the body: regulates organ volumes and act as sphincters , moves blood, urine, air, food and fluids, sperm
• Skeletal muscle contraction produces heat

Question 2

Describe three functional characteristics of muscle tissue

Answer 2

1. Electrical excitability - The muscle receives and responds to a stimulus which causes muscle action potentials which in turn cause muscle contraction
2. Contractibility - The ability of the muscle to contract when stimulates, enables tension to maintain a body position or causes the muscle to shorten to produce movement
3. Extensibility - The ability of muscle to stretch without being damaged (within limits) and to return to its original shape after contraction or extension

Question 3

Name the three types of muscle

Answer 3

1. Skeletal Muscle
2. Smooth (visceral) Muscle
3. Cardiac Muscle

Question 4

State the general location and function for each type

Answer 4

Skeletal Muscle: Location - Attached to bones,
Function: to produce skeletal movement

Cardiac Muscle
Location - Heart,
Function: pump blood

Smooth Muscle: Location - Walls of blood vessels GI tract, Airways,
Function: regulates diameter of blood vessels and airways, propels food in GI (digestive) tract

Question 5

Define the terms atrophy and hypertrophy and give an example of what causes each

Answer 5

Atrophy
- Wasting away of muscles
- Caused by disease of the muscle or severing of the nerve supply

Hypertrophy
- Is the increase in the diameter of muscle fibres
- Resulting from very forceful, repetitive muscular activity

Question 6

Describe the difference between a tendon and a ligament

Answer 6

• Ligaments are fibrous connective tissue that connect bones to bones and serve to hold structures together
• Tendons are fibrous connective tissue that attach muscles to bone or other body structures.

Question 7

Describe the main age related change that occurs to muscle tissue

Answer 7

• Decreased muscle strength (due to less muscle mass)
• Skeletal muscle is replaced by fibrous connective tissue and fat
• Decreased reflexes (due to slower neuron function)
• A slow, progressive loss of skeletal muscle mass

Question 8

State two specific functions of the pelvic floor muscles

Answer 8

• Support the pelvic organs
• Act as sphincters of the urethra and rectum

Question 9

Name three muscles used for IM (intramuscular) injections

Answer 9

• Gluteus Medius
• Lateral quadriceps (vastus lateralis)
• Deltoid muscles