Anatomy and Physiology 2-Chamberlain-Exam 1-Study Guide

Properties of muscles

• Excitability: Ability of muscle to respond to stimuli.

• Contractility: Ability of muscle to contract or shorten its size.

• Extensibility: Ability of muscle to stretch.

• Elasticity: Ability of muscles to return to original length after stretching.

Fusiform Muscles

A muscle that has the shape of a spindle, which is wider in the middle and narrowing towards both ends. An example is biceps brachii.

Parallel muscle

A muscle with a common point of attachment, with fascicles running parallel to each other. Ex. Rectus abdominis

Circular Muscle

These muscles appear circular in shape and are normally sphincter muscles that surround an opening such as the mouth Ex. Orbicularis Oculi

Convergent Muscle

fan-shaped-broad at one end and narrower at the other. Example: Deltoid (shoulder)

Cross bridge Formation

formed from the binding of actin with myosin. The formation shows muscle shortening caused by the movement of the contractile protein. The cross-bridge muscular contraction cycle is identified in all muscle types, including cardiac, smooth, and skeletal muscles. Cross-bridge cycling is caused by the cyclic attachment and detachment of contractile proteins.

Power stroke

The attachment of a myosin head from the thick filament to an active site on actin on the thin filament is a cross bridge.

Energy

-Mitochondria

-Glycolysis,

-Krebs Cycle (most efficient)

-Creatine (least efficient)

Insertion

further away, attachment Ex. Biceps brachii

Actions

Concentric-muscle shortens

Eccentric-lengthens

Isometric-remains the same

Function of muscle

Innovation

The nerve that operates

Afferent neurons

Carry information from sensory receptors found all over the body towards the central nervous system

Efferent neurons

Carry motor information away from the central nervous system to the muscles and glands of the body in order to initiate an action

Voltage gated channels

Respond to direct changes in membrane potential

Ligand-gated channels

Respond to chemical stimuli

Mechanical gate

Respond to mechanical vibration or pressure stimuli

Postsynaptic potential

when you add spatial summation (presynaptic neurons)

Muscle Identification

Pectoralis major
Latissimus dorsi
Deltoid
Rotator cuff: (supraspinatus, infraspinatus, subscapularis, teres major)
Biceps brachii
Triceps brachii
Brachioradialis

Quadriceps on Thigh

• Rectus femoris.

• Vastus lateralis.

• Vastus medialis.

• Vastus intermedius

L F E

• balance

• first-class lever is a spine

• seesaw

E L F

• power,

• crowbar

• leverage

• ankles

F E L

• rowing

• chopsticks

• Advantage: range of motion

• Disadvantage: decrease in power

Functional Classification of Neurons

• Sensory

• Motor/efferent

• Inter/association

Types of Neurons

• Multipolar-Most Common

• Unipolar-Sensory Receptors

• Bipolar-Retina of the Eye