Unit 2 Quizzes

What three things does striated muscle contain that smooth muscle does not?

Z bands, t-Tubules, sarcoplasmic reticulum

What type of muscle is under the control of the motor cortex?

skeletal muscle

What steps of skeletal muscle contraction does ATP directly cause?

“cocking back” of the myosin head, the release of myosin from actin’s myosin binding site

Muscle cells are “excitable” and can undergo action potentials. (True/False)

True

Order the levels of skeletal muscle organization from largest to smallest (muscle fibers, myosin and actin, myofibril, sarcomere, thick and thin filaments, whole muscle)

whole muscle, muscle fibers, myofibril, sarcomere, thick and thin filaments, myosin and actin

Diastole is defined as ____ of the heart muscles.

relaxation

Systole is defined as ____ of the heart muscles.

contraction

Stenosis means that the valve is __________.

a little bit closed when it should be open

Insufficiency means that the valve is __________.

a bit open when it should be closed

The first heart sound (lub) is when the ____ valves close.

AV

The second heart sound (dub) is when the ____ valves close.

pulmonary/aortic

The volumes of blood in the left and right ventricle are the same. (True/False)

True

The pressures of the elft and right ventricles are the same. (True/False)

False

From vena cava to aorta, how does blood flow?

vena cava, right atria, right ventricle, lungs, left atria, left ventricle, aorta

How does blood flow from aorta to vena cava?

aorta, arteries, arterioles, capillary beds, venules, veins, vena cava

What are the names and locations of the pressure sensing receptors?

baroreceptors, aorta and carotid artery

Which bands and zones of a skeletal muscle shorten during contracting?

I Band and H-zone

What is the percent of O2 in the air?

21%

What is the percent CO2 in the air?

0.03%

The surfactant keeps alveoli from deflating and breaks up water tension. (True/False)

True

Name three ways to increase the force of contraction:

• Increase how rapid the action potential stimulate contraction from an individual motor unit

• Increase number of motor units activated

• Increase number of muscle cells in a motor unit

Why is diffusion not sufficient in complex organisms?

Distance