What are the 4 characteristics that all muscle tissue has?
- Excitability
- Contractility
- Extensibility
- Elasticity
These characteristics define the functional properties of muscle tissue.
Name 2 differences and 1 similarity between smooth and cardiac muscle tissue.
Differences: Location: Smooth muscle is found in walls of hollow organs (like intestines and blood vessels), while cardiac muscle is found only in the heart.
Control: Smooth muscle is involuntary and not striated, whereas cardiac muscle is involuntary but striated.
Similarity: Both are involuntary muscles.
Understanding these differences and similarities is crucial for studying muscle physiology.
What is this structure?
Muscle tissue
Identification of muscle tissue is essential for understanding its functions.
What membrane covers muscle tissue?
Epimysium
The epimysium is a connective tissue sheath that surrounds the entire muscle.
Name the 4 functions of the muscular system.
- Movement
- Posture
- Joint stability
- Heat production
These functions highlight the importance of muscles in the human body.
What type of muscle tissue is this and how do you know?
Skeletal muscle
Identification can be based on striations and voluntary control.
Is it voluntarily or involuntarily controlled?
Voluntarily
Skeletal muscle is under conscious control, unlike smooth and cardiac muscles.
Identify these 3 structures.
Muscle fibers, myofibrils, sarcomeres
Understanding these structures is key to muscle function.
Why are neurotransmitters needed in a neuromuscular junction?
To transmit signals from nerve to muscle
Neurotransmitters facilitate communication between the nervous system and muscles.
What are these filaments?
Actin and myosin
These filaments are essential for muscle contraction.
They interact according to the _______ _______ theory.
Sliding filament
This theory explains how muscles contract at the molecular level.
Name 1 event that must occur before myosin heads can form cross-bridges.
Calcium ion release
Calcium ions are crucial for initiating muscle contraction.
What happens to a sarcomere during a myosin power stroke?
It shortens
The shortening of the sarcomere is the fundamental mechanism of muscle contraction.
Why are muscles stiffly contracted after death?
Rigor mortis
Rigor mortis occurs due to the lack of ATP, preventing myosin from detaching from actin.
What is the role of Na+ and K+ in the neuromuscular junction?
Generate action potentials
Sodium and potassium ions are essential for the propagation of electrical signals in muscle cells.
The brachioradialis muscle is on the forearm. It attaches to the humerus and the radius. Which attachment is the insertion and which is the origin?
Origin: Humerus; Insertion: Radius
Understanding muscle attachments is important for studying movement mechanics.
When rowing, the trapezius contracts. What muscle would be an antagonist during this motion?
Sternocleidomastoid
Antagonistic muscles work in opposition to facilitate movement.
Muscles that work alongside the prime mover are called ____________.
Synergists
Synergists assist the prime mover in performing a movement.
What are the 2 types of cellular respiration?
- Aerobic respiration
- Anaerobic respiration
These types of respiration are crucial for energy production in muscle cells.
