Muscle Tissue 🏋️‍♀️ 2

Question 1

Skeletal Muscle

Answer 1

Muscle type attached to the skeleton, under voluntary control, with multinucleated cells and organized myofilaments.

Question 2

Cardiac Muscle

Answer 2

Muscle found in the heart, functioning involuntarily with branched cells and intercalated discs, enriched in mitochondria and glycogen stores.

Question 3

Diad

Answer 3

A complex consisting of one T tubule and one adjacent terminal cisternae at the Z line, involved in the release of calcium ions in muscle contraction.

Question 4

Muscle Contraction

Answer 4

Involves the release of free calcium ions from the sarcoplasmic reticulum, activation of myosin light chain kinase, and sliding of actin and myosin filaments to shorten the muscle fiber.

Question 5

Actomyosin Cross-bridge Cycle

Answer 5

The sequence of events involving attachment, release, bending, force generation, and reattachment between actin and myosin during muscle contraction.

Question 6

Muscle Spindle

Answer 6

A specialized stretch receptor within muscle that senses changes in muscle length, aiding in proprioception.

Question 7

Hormones

Answer 7

Atrial natriuretic peptide and brain natriuretic peptide are hormones involved in regulating blood volume and blood pressure in the body.

Question 8

Sarcoplasmic Reticulum

Answer 8

An organelle found in muscle cells that stores and releases calcium ions necessary for muscle contraction. It is less developed in cardiac muscle than in skeletal muscle.

Question 9

Intercalated Discs

Answer 9

Attachment sites between adjacent cardiac myocytes, containing structures like fascia adherens, maculae adherentes, and gap junctions.

Question 10

Purkinje Fibers

Answer 10

Specialized muscle cells located in the heart that conduct electrical impulses to synchronize ventricular contraction. They have a pale-staining appearance due to few myofibrils.

Question 11

Sliding Filament Model

Answer 11

The theory that explains muscle contraction as the result of myofilaments sliding past each other, rather than changing in length.

Question 12

Muscular Dystrophies

Answer 12

A group of genetic disorders characterized by ultrastructural defects in muscle cells, such as Duchenne muscular dystrophy involving myofibril degeneration.

Question 13

Smooth Muscle

Answer 13

Muscle type located in various organs, functioning involuntarily, with tapered cells and lacking striations.

Question 14

Skeletal Muscle

Answer 14

Large, elongated cells found in skeletal muscles for voluntary movements, characterized by striations, multiple nuclei per cell, and a well-developed sarcoplasmic reticulum.