Question

1.The" pacemaker" of the heart is the ______.

Group of answer choices

ventricles

bundle of His

SA node

Purkinje fibers

2.The foramen ovale is a connection between the pulmonary trunk and the aorta of the fetus.

Group of answer choices

True

False

3.Which can be used to characterize blood flow in the human body?
a: Veins always carry deoxygenated blood.
b: Veins carry blood toward the heart.
c: Arteries always carry oxygenated blood.
d: Arteries carry blood away from the heart.
e: There is a unidirectional blood flow.

Group of answer choices

b,c,d,e

d,e

a,c,d,e

b, d, e

a,b,c,d,e

4.Parasympathetic innervation decreases the heart rate, but generally tends to have no effect on the force of contractions.

Group of answer choices

True

False

5.The endocardium _______.

Group of answer choices

is a serous membrane

is the outer layer of the parietal pericardium

lines the chambers of the heart

is composed of cardiac muscle

6.The internal wall surface of each ventricle displays large, textured, irregular muscular ridges called _________.

Group of answer choices

trabeculae carnae

pectinate muscles

chordae tendineae

atrioventricular opening

conus arteriosus

7.Which of the following is a branch off the left coronary artery?

Group of answer choices

posterior interventricular a.

right marginal a.

coronary sinus

circumflex a.

8.The epicardium is another name for the ______.

Group of answer choices

myometrium

pericardium

parietal layer of the serous pericardium

visceral layer of the serous pericardium

myocardium

9.About seventy percent of the ventricle filling is achieved passively without the contraction of the atria.

Group of answer choices

True

False

10.Which valve prevents the backflow of blood into the left ventricle when the ventricles relax?

Group of answer choices

Aortic semilunar valve

Right atrioventricular valve

Left atrioventricular valve

Pulmonary semilunar valve

11.The cell-to-cell contacts of the cardiac muscle fibers are called ______.

Group of answer choices

sarcoplasmic reticulum

intercalated discs

cardiac discs

Z discs

T-tubules

12.The left atrioventricular valve is also known as the _____.

Group of answer choices

mitral

aortic

semilunar

tricuspid

13.The respiratory membrane _______.

Group of answer choices

is also called the pleurae

is found in the nasal cavities

is pseudostratified columnar epithelium

is formed by the wall of an alveolus, sandwiched basement membranes, and the wall of a pulmonary capillary

14.Secondary bronchi branch directly off primary bronchi, and enter lobes in the lungs.

Group of answer choices

True

False

15.The right lung has only 2 lobes.

Group of answer choices

True

False

16.Which of the following cells wanders through alveoli removing pathogens and particles, like dust?

Group of answer choices

Type II (septal) cells

alveolar squamous cells

platelets

alveolar macrophages

Answer 1

Ans. 1. option C is the correct answer.

Explanation;- The" pacemaker" of the heart is the the SA node. It is also called as the sinoauricular node. It is responsible for the pace of the hearts. It is also called as the natural pacemaker of heart.

Ans.2. The given statement is the false statement.

Explanation;- It is not the foramen ovale. Foramen ovale is connection which moves blood from the right atrium of the heart to the left atrium.

Ans.3. Option D is the correct answer.

Explanation;- The flow of blood in the human body is the unidirectional flow of the body. The arteries are the blood vessels that carries the blood away from the heart and veins takes the blood towards the hearts.

Ans.4. The given statement is the true statement.