1. Structure and function of body system

Question 1

Axial and Appendicular skeleton

Answer 1

Axial: skull, column, ribs and sternum
Appendicular: limbs system

Question 2

Column vertebrae numbers

Answer 2

5 cervical, 12 thoracic, 5 lumbar, 5 sacral, 3-5 coccygeal

Question 3

Categories of joint

Answer 3

Fibrous -> cartilaginous -> synovial
Synovial are: Uniaxial, biaxial e multiaxial

Question 4

Layers of muscle tissue

Answer 4

Epimysium contiguous with tendons cover the muscle system.
Perimysium, fasciculi of muscle fibers
Endomysium, single muscle fiber contiguous with sarcolemma.

Question 5

Motor unit structure

Answer 5

Motor neuron that innervate a group o muscle fibers, linked by the neuromuscular junction

Question 6

myofibrils

Answer 6

They dominate the sarcoplasma, and are myosin and actin. Their connection is a cross bridge

Question 7

Strain and sprain

Answer 7

Muscle get strain
Tendon get sprain

Question 8

Sarcomere structure and size

Answer 8

Length 2.5u
Myosin is surrounded by 6 actine
Actine is surrounded by 3 myosin

Question 9

Structure: Z [I - A(H) - I] Z
What band do not change length during contraction ?

Answer 9

A band do not change.

Question 10

Steps for a muscle contraction

Answer 10

1. Motor neuron fires an electrical impulse called action potential
2. Acetylcholine is released across the NJ
3. Calcium stored into the sarcoplasmic reticulum is spread into the sarcomere by T-tubules
4. Actine and myosin link and contracts

Question 11

Actine and Ca+

Answer 11

When Ca+ reach actine, Troponin binds with Calcium ions, and Tropomyosin moves and let the actine active site for the myosin head attach.

Question 12

In resting phase how the actine a myosin acts ?

Answer 12

There’s a little concentration of Ca+ in the myofibrils and even if actine site is covered, there’s tension between some myosin and actine

Question 13

Power stroke comes from ?

Answer 13

hydrolysis of ATP into ADP and phosphate and a release of energy.

Question 14

Twitch and tetanus

Answer 14

Twitch: single brief contraction
Tetanus: merge of twitches in sequences

Question 15

Classification motor units

Answer 15

Ia slow, IIa fast aerobic, IIx fast anaerobic

Question 16

Power and strength came from

Answer 16

Increase in firing rates of singles MU and larger recruitment of them

Question 17

Muscle spindle

Answer 17

Intrafusal or extrafusal fibers the run along the muscle fibers and provide information about the length of the muscle. If danger length occur so the m.spindle create a greater activation of the agonist muscle

Question 18

Golgi tendon organs

Answer 18

Located as dots in the tendon, if the tension on it increase, they inhibit the motor neuron

Question 19

Blood path

Answer 19

(from big circulation)
Vena cava - Right atrium - tricuspide valve - right ventricle - pulmonary artery
(get O2 in lungs small circulation)
Pulmonary vein - left atrium - mitral valve - left ventricle (bigger) - Aorta
(to big circulation with O2)

Question 20

Sinoatrial node SA and Purkinje fibers

Answer 20

pacemaker of heart rhythm of impulse
AV nodes pass the impulse to ventricle and Purkinje fibers conduct to all parts of ventricles.

Question 21

Waves P Q R S T

Answer 21

P depolarization of atria
QRS depolarization of ventricle
T repolarization of ventricle

Question 22

Exchange of gases occur in

Answer 22

Alveoli with diffusion