muscles and integument

Skeletal, cardiac, and smooth muscles are the three types of muscle tissue in the body.

Voluntary muscle that moves the skeleton; it is mostly consciously controlled, but also has automatic functions.

Involuntary muscle found only in the heart; it pumps blood throughout the body (heart contraction).

Involuntary muscle found in the walls of many internal organs; it controls functions like digestion and blood pressure.

Tendons connect muscles to bones; aponeuroses connect muscle to bone or muscle to another muscle.

The more stable attachment point of a muscle, typically proximal and stationary during contraction.

The attachment point that moves during muscle contraction, typically more distal.

The muscle primarily responsible for a specific movement.

The muscle that opposes the action of the prime mover, helping to smooth movement or create rigidity.

A muscle that works alongside the prime mover to assist in movement.

A muscle that stabilizes a joint during movement to allow other muscles to work efficiently.

The basic, repeating functional unit of a muscle fiber, responsible for contraction.

A long, thread-like structure within a muscle cell containing contractile protein filaments.

Individual sarcomeres shorten, which collectively leads to a noticeable muscle fiber shortening.

A thin connective tissue layer that wraps around individual muscle fibers.

Connective tissue that bundles groups of muscle fibers (fascicles) together.

The outer layer of connective tissue that encases the entire muscle.

The site where a motor nerve fiber connects to a muscle fiber.

Small sacs at the end of a nerve fiber that contain acetylcholine, a neurotransmitter.

One motor nerve fiber and all the muscle fibers it controls.

1. Nerve impulse releases acetylcholine. 2. Acetylcholine binds to sarcolemma receptors. 3. Impulse travels along sarcolemma and T tubules. 4. Ca++ ions released from sarcoplasmic reticulum. 5. Ca++ initiates contraction process. 6. ATP powers the contraction.

The continuous process of hair growth and shedding, influenced by hormones and environmental factors.

The active growth phase of hair, where new cells are added to the hair root, resulting in increased hair length.

The shedding of a large amount of hair at one time, often triggered by hormonal changes or stress.

A pigment produced by melanocytes, responsible for yellow or reddish hair colors in dogs.

A pigment produced by melanocytes, responsible for brownish-black hair colors in dogs.

Specialized hairs with numerous nerve endings, commonly known as whiskers. They are found throughout the coat and help an animal sense its surroundings.

Another name for tactile hairs, referring to the large blood sinus within their follicle.

Small muscles attached to hair follicles that can cause hair to stand on end when an animal is frightened or cold.

Glands found throughout the body that produce sebum, an oily substance that helps keep the skin moist and supple.

Sebum traps moisture, provides antibacterial and antifungal protection, and can also clog hair follicles leading to acne.

Glands that secrete sweat to regulate body temperature. Horses have more sweat glands than other animals.

A type of sweat gland found in dogs that secretes sweat directly onto the skin surface, often found in the foot pads.

A type of sweat gland found in dogs that secretes sweat into hair follicles, often present in the ear canals. These glands are more common in dogs with long hair.

Calcium ions (Ca++) are released from the sarcoplasmic reticulum into the myofibril, triggering muscle contraction.

A network of membrane-bound sacs within muscle fibers that stores and releases calcium ions (Ca++).

The two primary proteins involved in muscle contraction. Actin filaments are thin, myosin filaments are thick.

Projections on myosin filaments that attach to actin filaments and pull them during muscle contraction.

A muscle fiber either contracts fully or not at all; there is no partial contraction.

The ability of the nervous system to precisely control muscle contractions through repeated practice and training.

A single, brief contraction of a muscle fiber in response to a stimulus.

The delay between nerve stimulation and the beginning of muscle fiber contraction.

The period of muscle shortening during a twitch.

The period of muscle relaxation after a twitch.

Adenosine triphosphate; the primary energy source for muscle contraction.

Adenosine diphosphate; a byproduct of ATP breakdown, which releases energy.

A molecule stored in muscle that recharges ADP back into ATP.

The process of breaking down nutrients using oxygen to create ATP.

The process of breaking down nutrients without oxygen to create ATP, producing lactic acid as a byproduct.

Specialized junctions between cardiac muscle cells that allow for rapid communication and coordinated contraction.

The pacemaker of the heart; generates the electrical impulse that initiates each heartbeat.

Part of the autonomic nervous system that increases heart rate and force of contraction.

Part of the autonomic nervous system that decreases heart rate and force of contraction.

Found in sheets of cells in the walls of hollow organs; responsible for involuntary contractions.

Found in discrete groups of cells; responsible for precise, localized contractions.

Structures within smooth muscle cells where actin and myosin filaments attach, similar to Z lines in skeletal muscle.

A hormone that stimulates uterine contractions during childbirth.