CSS - PMS - CCE - PCS - General Science
Organs
Which muscle is the principal muscle of quiet inspiration?
A. Diaphragm
B. Biceps
C. Rectus abdominis
D. Trapezius
Correct Answer: A
Contraction of the diaphragm enlarges the thoracic cavity and draws air into the lungs.
CSS - PMS - CCE - PCS - General Science
Organs
How many lobes does the left lung normally have?
A. One
B. Two
C. Three
D. Four
Correct Answer: B
The left lung has two lobes: superior and inferior.
CSS - PMS - CCE - PCS - General Science
Organs
Which lung has three lobes?
A. Left lung only
B. Right lung only
C. Both lungs
D. Neither lung
Correct Answer: B
The right lung has three lobes; the left lung has two to accommodate the heart.
CSS - PMS - CCE - PCS - General Science
Organs
Where does gas exchange primarily occur in the lungs?
A. Bronchi
B. Alveoli
C. Trachea
D. Pleura
Correct Answer: B
Alveoli provide a thin, large surface for exchange of oxygen and carbon dioxide.
CSS - PMS - CCE - PCS - General Science
Organs
Which structure is commonly called the windpipe?
A. Esophagus
B. Trachea
C. Pharynx
D. Ureter
Correct Answer: B
The trachea conducts air from the larynx toward the bronchi.
CSS - PMS - CCE - PCS - General Science
Organs
Which membrane surrounds the heart?
A. Pleura
B. Pericardium
C. Peritoneum
D. Meninges
Correct Answer: B
The pericardium is the sac surrounding the heart.
CSS - PMS - CCE - PCS - General Science
Organs
The heart is located mainly in which body cavity?
A. Abdominal cavity
B. Thoracic cavity
C. Pelvic cavity
D. Cranial cavity
Correct Answer: B
The heart lies in the mediastinum within the thoracic cavity.
CSS - PMS - CCE - PCS - General Science
Organs
Which vessels supply the heart muscle itself with oxygenated blood?
A. Pulmonary veins
B. Coronary arteries
C. Hepatic veins
D. Renal arteries
Correct Answer: B
The coronary arteries supply the myocardium.
CSS - PMS - CCE - PCS - General Science
Organs
Which blood vessels carry oxygenated blood from the lungs to the heart?
A. Pulmonary arteries
B. Pulmonary veins
C. Venae cavae
D. Coronary arteries
Correct Answer: B
Pulmonary veins carry oxygenated blood to the left atrium.
CSS - PMS - CCE - PCS - General Science
Organs
Which blood vessel carries deoxygenated blood from the heart to the lungs?
A. Pulmonary vein
B. Pulmonary artery
C. Aorta
D. Vena cava
Correct Answer: B
The pulmonary artery is an exception among arteries because it carries deoxygenated blood.
CSS - PMS - CCE - PCS - General Science
Organs
Which is the largest artery in the human body?
A. Pulmonary artery
B. Aorta
C. Carotid artery
D. Femoral artery
Correct Answer: B
The aorta is the largest artery and carries blood from the left ventricle to the body.
CSS - PMS - CCE - PCS - General Science
Organs
Which valve lies between the right atrium and right ventricle?
A. Mitral valve
B. Tricuspid valve
C. Aortic valve
D. Pulmonary valve
Correct Answer: B
The tricuspid valve separates the right atrium from the right ventricle.
CSS - PMS - CCE - PCS - General Science
Organs
Which valve lies between the left atrium and left ventricle?
A. Tricuspid valve
B. Mitral valve
C. Pulmonary valve
D. Aortic valve
Correct Answer: B
The mitral, or bicuspid, valve separates the left atrium from the left ventricle.
CSS - PMS - CCE - PCS - General Science
Organs
Which chamber pumps deoxygenated blood to the lungs?
A. Left ventricle
B. Right ventricle
C. Left atrium
D. Right atrium
Correct Answer: B
The right ventricle pumps deoxygenated blood through the pulmonary artery to the lungs.
CSS - PMS - CCE - PCS - General Science
Organs
Which chamber of the heart pumps oxygenated blood to the body?
A. Right atrium
B. Right ventricle
C. Left atrium
D. Left ventricle
Correct Answer: D
The left ventricle pumps oxygenated blood into the aorta for systemic circulation.
CSS - PMS - CCE - PCS - General Science
Organs
How many chambers are present in the human heart?
A. Two
B. Three
C. Four
D. Five
Correct Answer: C
The human heart has two atria and two ventricles, making four chambers.
CSS - PMS - CCE - PCS - General Science
Organs
The spinal cord is protected mainly by which structure?
A. Ribs
B. Vertebral column
C. Skull
D. Pelvis
Correct Answer: B
The vertebral column encloses and protects the spinal cord.
CSS - PMS - CCE - PCS - General Science
Organs
Which lobe of the brain is important for planning, judgment and voluntary motor control?
A. Frontal lobe
B. Occipital lobe
C. Temporal lobe
D. Insula
Correct Answer: A
The frontal lobe contributes to executive functions and contains the primary motor cortex.
CSS - PMS - CCE - PCS - General Science
Organs
Which lobe of the brain is strongly associated with hearing?
A. Temporal lobe
B. Occipital lobe
C. Frontal lobe
D. Parietal lobe
Correct Answer: A
The temporal lobe contains the primary auditory cortex.
CSS - PMS - CCE - PCS - General Science
Organs
Which lobe of the brain is primarily associated with vision?
A. Frontal lobe
B. Occipital lobe
C. Temporal lobe
D. Parietal lobe
Correct Answer: B
The primary visual cortex lies in the occipital lobe.