Old Exam

Question 1

Generally, muscles that contract to make the angle of a joint more narrow are:

Answer 1

Flexors

Question 2

Generally, muscles that contract to make the angle of a joint wider are:

Answer 2

Extensors

Question 3

If the shape of the joint allows, muscles may also move the bones sideways, toward the body:

Answer 3

Adductors

Question 4

If the shape of the joint allows, muscles may also move the bones sideways, away from it (_____).

Answer 4

Abductors

Question 5

Generally, extensor muscles are located on the _____ side of the limb.

Answer 5

Cranial and dorsal

Question 6

Generally, flexor muscles are located on the _____ side of the limb.

Answer 6

Caudal and palmar

Question 7

Muscles that move the forelimb forward:

Answer 7

Brachiocephalicus

Omotransversarius

Sternomandibularis

Biceps brachii

Brachialis

Extensor carpi radialis

Common and lateral digital extensors

Thoracic portion of trapezius

Subclavicus

Supraspinatus

Question 8

Muscles that draw the limb backward:

Answer 8

Latissimus dorsi

Teres major

Superficial and deep digital flexor

Long and lateral head of triceps brachii

Subscapularis

Flexor carpi radialis and ulnaris

Rhomboideus

Question 9

Biceps femoris (2 heads)

Joints and action

Answer 9

Hip and stifle joints

Extends hip, stifle and hock

Abductor

Question 10

Common and lateral digital extensor

Joints and action

Answer 10

Extend carpus and foot joints

Front limb

Question 11

Superficial and deep digital flexor

Answer 11

Flexes carpus and foot joints

Front limb

Question 12

Brachiocephalicus and omotransversarius

Limb and action

Answer 12

Neck muscles/Front limb

Bring the limb forward

Question 13

Muscles that flex the hip, extend the stifle and abduct the hind limb

Answer 13

Fascia glutea, superficial gluteus, and tensor fascia lata

Question 14

When _____ is the main fuel = aerobic

When _____ is the main fuel = anaerobic

Answer 14

Oxygen - aerobic

Glycogen - anaerobic

Question 15

_____ heads attach to actin and shorten the sarcomere as they contract and relax

Answer 15

Myosin

Question 16

Horse limb anatomy is important to learn because the value of horses lies in their ability to _____

Answer 16

Move

Question 17

Muscles can only _____ and relax.

When a muscles passes over the apex of a joint it causes the joint to _____

Answer 17

Contract

Extend

Question 18

5 Functions of the Skeleton

Answer 18

Protect internal organs

Give muscles something to attach to for movement

Give the body structure

Question 19

4 Functions of Skeletal muscles

Answer 19

Move Skeleton

Support Skeleton

Maintain joint stability

Produce heat by shivering

Question 20

Define reciprocal apparatus

Answer 20

The hock cannot move without the stifle

Question 21

Gluteal tongue - why is it important?

Answer 21

Gives muscle more surface area to be able to control the force and connect the hindlimb to the frontlimb so the horse can move properly and project motion from the hind limb forward to the front limb

Question 22

Explain the bow and string system

Answer 22

The back muscles hollow the back when they contract, so in order to round the back abdominals need to contract so it holds the back taut.

The rider is the “arrow”

The back is the “bow”

Abdominals are the “string”

Question 23

Muscles most important to ridden horse

Answer 23

Iliopsoas and psoas

Question 24

Horse’s natural response to weight of a rider

Answer 24

Tense the psoas and iliopsoas - which prevents him from stepping under with hind legs

If these muscles do not soften and become supple, the horse will never engage his hindquarters correctly. Structures in mid-back and stifle bear brunt of power produced by hind limb muscles, which become damaged in the process

Warm-up exercises to unlock these muscles

Question 25

Describe Type I muscle fibers

Answer 25

Slow twitch fibers

Highly oxidative

Endurance horses (slow to fatigue)

Narrow

Less power

1 motor neuron per 20-30 muscle fibers

Question 26

Describe Type IIA

Answer 26

Fast twitch fibers

Highly oxidative

Good for race horses

High myoglobin (oxygen use)

Question 27

Describe Type IIB

Answer 27

Fast twitch fibers

Low oxidative

Good for bursts of energy (rapidly fatigued)

Ex: Quarter horses barrel racing

White sprint muscle

1 motor neuron per 2,000 muscle fibers

Question 28

Why is it hard to breed a race horse to run 1 1/4 miles

Answer 28

Because its longer than a sprint race and shorter than an endurance race. Horses need sprinting muscles that can last a long time. Type IIA is the best for race horses to have as it is in between.