Types of Muscle Fibres Biology Class

Questions and Answers

They are adapted for fast contraction.

They rely on anaerobic respiration.

They have less myoglobin.

They have a higher number of mitochondria. (correct)

Utilizes aerobic respiration.

Tendency to accumulate lactic acid. (correct)

Slower contraction speed.

Higher concentration of blood capillaries.

Mainly bones. (correct)

Soft connective tissues.

Cartilage and ligaments.

Muscle tissue.

<p>Aerobic respiration.</p> Signup and view all the answers

<p>Red muscle fibers contract more slowly.</p> Signup and view all the answers

Study Notes

Red Muscle Fibres:
- Contain high levels of myoglobin, leading to a reddish color and enhanced oxygen storage for prolonged activity.
- Have an extensive network of blood capillaries, facilitating greater oxygen delivery.
- Rich in mitochondria, which support aerobic respiration and energy production.
- Exhibit slower contraction speeds, making them suited for endurance activities.
- Commonly found in human back muscles, essential for maintaining posture.
White Muscle Fibres:
- Characterized by lower levels of myoglobin, resulting in a whitish appearance due to reduced oxygen storage capacity.
- Fewer blood capillaries limit oxygen supply, leading to quicker fatigue.
- Contain fewer mitochondria, primarily relying on anaerobic respiration for energy, resulting in lactic acid build-up.
- Feature a higher concentration of sarcoplasmic reticulum (SR), enabling rapid contractions.
- Predominantly located in eye muscles, allowing for quick movements and reflex actions.

Composed primarily of skeletal connective tissues, with bones serving as the fundamental structure.
Bone matrix is solid and hard yet pliable, designed to withstand mechanical stresses.
Calcium is a key component of the bone matrix, crucial for maintaining strength and hardness in bones.