The Function of Muscles Flashcards
three types of muscle
smooth, cardiac, skeletal
Describe smooth muscle
lines organs and blood vessels, not voluntary controlled, not striated; one nucleus per cell
Describe Cardiac muscle
striated; looks like zebra stripes; cells have 1-2 nuclei; in the heart only; not voluntarily controlled
Describe skeletal muscle
striated; attaches to bones or tendons; voluntarily controlled; multi-nucleate
Jobs of the Muscles
posture, generates body temperature, cause movement in internal organs, and important for movement of the body
What do astronauts show significant signs of? Where
Atrophy; in calf, quads, back, and neck muscles
What does smooth muscles do?
Involuntarily control organs
What is peristalis?
food pushed through the GI tract
What surroundes the testes?
cremaster and dartos
What two reasons cause muscles to create heat when they contract?
ATP hydrolysis is an exothermic reaction and friction between muscle fibers
Generally, what is heat considered? When is this not true?
unwanted byproduct of muscles working; shivering
What are the two separate points that muscles attach to? What are they?
Origin and insertion; origin is a fixed attachment and insertion moves with the contraction
Muscles work in what? What are they? What do they do?
pairs; they are called agonists and antagonists; agonists carry out the primary motion and antagonists oppose it and can reverse it
What runs along the humerus? What bones does it attach to, and how many origins and insertions? What does it allow?
Biceps brachii; Attaches to the scapula with two origins and the radius with one insertion; it allows for flexion of the elbow (action)
What does the triceps brachii connect to, and how many origins? Where and how many insertions? What does it allow?
It connects its three heads from the scapula and humerus (3 origins), to the ulna (one insertion). It allows the extension of the elbow
