Muscles III

Question 1

Muscles of the lower limb:

Answer 1

-iliopsoas
-gluteals (3)
-adductors (5+)
-quadriceps (4)
-hamstrings (4)
-Tibialis anterior
-calf muscles (2): gastrocnemius, soleus

Question 2

Iliopsoas attachments:

Answer 2

Proximal:
-anterior lumbar vertebrae
-iliac fossa
Distal:
-medial proximal femur

Question 3

Iliopsoas function

Answer 3

-hip flexion
-pelvis tilt forward

Question 4

Gluteals (3) attachments:

Answer 4

Proximal:
-outer surface of ilium
Distal:
-lateral & posterior proximal femur

Question 5

Gluteals function:

Answer 5

-hip extension (Maximus) & pelvis tilt backwards
-hip abduction (medius & minimus)

Question 6

adductors (5) attachments:

Answer 6

Proximal:
-pubis
Distal:
-medial femur

Question 7

Adductors functions:

Answer 7

Hip adduction

Question 8

Muscles that move the femur & tibia: quads attachment

Answer 8

Proximal:
-proximal femur (3 Vastus muscles)
-anterior ilium (rectus femoris)
Distal:
-anterior proximal tibia (tibial tuberosity)

Question 9

Quads function:

Answer 9

-knee extension
-hip flexion (rectus femoris only)

Question 10

Muscles that move the femur & tibia: hamstrings attachments

Answer 10

Proximal:
-Ischial tuberosity
Distal:
-posterior medial & lateral proximal tibia

Question 11

Hamstrings function:

Answer 11

-hip extension
-knee flexion

Question 12

Ankle movement:

Answer 12

Source of confusion of foot/toes & flexion (closing) ankle joint

Question 13

Ankle movement: plantar flexion

Answer 13

-pointing foot, heel raising
Muscles: soleus, gastrocnemius

Question 14

Ankle movement: dorsi flexion

Answer 14

-hooking up the foot, raise toes (not heals) off floor
Muscles: Tibialis anterior

Question 15

Muscles that move the foot: Tibialis anterior attachments

Answer 15

Proximal:
-proximal (anterior) 2/3 of tibia
Distal:
-top of 1st metacarpal

Question 16

Tibialis anterior function:

Answer 16

-dorsiflexion of the foot

Question 17

Muscles that move the foot: soleus attachments

Answer 17

Proximal:
-posterior proximal tibia
Distal:
-calcaneus

Question 18

Soleus function:

Answer 18

-foot plantar flexion

Question 19

Muscles that move the foot: gastrocnemuis attachments

Answer 19

Proximal:
-posterior (medial & lateral) distal femur
Distal:
-calcaneus

Question 20

Gastrocnemius function

Answer 20

-knee flexor

Question 21

of muscles in body

Answer 21

-human body compromised of 324 muscles

Question 22

Muscle mass

Answer 22

-30-35% in women
-42-47% in men

Question 23

3 types of muscle:

Answer 23

-skeletal
-smooth
-cardiac

Question 24

Smooth muscleL (involuntary)

Answer 24

-in blood vessels, organs, eye iris, GI tract
-slow, uniform contractions
-fatigue resistant

Question 25

Cardiac muscle: involuntary

Answer 25

-self generating impulses
-features of both smooth & skeletal muscle tissues
-very fatigue resistant

Question 26

Skeletal muscle: (striated)

Answer 26

-connects body segments via tendons
-repeated contractions leads to fatigue
-voluntary

Question 27

Anatomy of single muscle cell (fibre):

Answer 27

-diameter of a thin human hair
-max. Length 12cm (4.5in)
-multinucleated cylindrical cell
-sarcolemma (cell membrane)
-sacroplasm (cytoplasm)
-the sacromere is the ‘functional’ unit of a muscle fibre (from z-line to z-line)
-a muscle contraction = many sarcomeres shortening (actin sliding over the myosin0

Question 28

Muscle fibre Myofibril

Answer 28

A muscle fibre contains many Myofibril which are made up of contractile proteins:
-actin (thin filament) forms a framework, & slides over myosin filaments
-myosin (think filaments)
Myofilaments: myosin & actin (comprise the sarcomere unit)