Muscle Tissue: Types and Functions

During a period of prolonged standing, which muscle property is primarily responsible for maintaining an upright posture?

Which type of muscle tissue is characterized by involuntary control, the presence of a single nucleus in each cell, and its involvement in processes such as peristalsis in the digestive tract?

A researcher is studying a muscle tissue sample under a microscope and observes branching cells connected by intercalated discs. Which function is the most likely role of this tissue?

Following a strenuous workout, a weightlifter's muscles lengthen to return to their resting state. Which property of muscle tissue is primarily demonstrated in this scenario?

During exercise, muscles generate heat as a byproduct of metabolic activity. Which of the following best explains the significance of this heat production in maintaining homeostasis?

Contractility allows muscles to contract (shorten) and relax to produce movement.
Extensibility enables muscles to extend or stretch, returning to their resting length.
Excitability (irritability) is the ability to be stimulated, responding to signals from nerves, hormones, and local stimuli.
Posture is maintained by continuous partial contraction of some skeletal muscles.
Heat production, a catabolic process, generates body heat and maintains homeostasis.
Movement occurs as muscles pull on bones (or other muscles), moving the body or its parts.
Protection is provided by muscles covering internal organs, supporting their weight, and preventing overstress on joints and bones.

Skeletal Muscle

Multinucleated structure with a regular arrangement of actin and myosin fibers, creating a striated appearance.
Functions to move the skeleton, notably the limbs.
Typically connected to bones or fascia.

Cardiac Muscle

Contains 1-2 nuclei with branching cells connected by intercalated disks organized as a syncytium for coordinated contraction.
Pumps blood through the circulatory system.
Located in the heart.

Smooth Muscle

Features one nucleus and lacks a regular arrangement of actin and myosin, appearing non-striated or smooth.
Causes goosebumps and moves food through the digestive tract and blood through the circulatory system.
Found in parts of viscera (organs, ducts) throughout the body.

Explore the key properties of muscle: contractility, extensibility, and excitability. Learn about the diverse functions of muscles in maintaining posture, producing heat, enabling movement, and providing protection. Discover the structure and function of skeletal muscle.