BIO 240 — Human Anatomy and Physiology

Question 1: Which chamber of the heart pumps oxygenated blood into the aorta?

•          Right atrium

•          Right ventricle

•          Left atrium

•          Left ventricle

Explanation: The left ventricle has the thickest muscular wall of all four chambers because it must generate enough pressure to pump oxygenated blood through the aorta and out to the entire systemic circulation.

Question 2: Which type of muscle tissue is voluntary and striated?

•          Cardiac muscle

•          Smooth muscle

•          Skeletal muscle

•          Visceral muscle

Explanation: Skeletal muscle is under conscious control and appears striated under a microscope due to the organized arrangement of actin and myosin filaments within its muscle fibers.

Question 3: The alveoli are the primary site of gas exchange in the respiratory system.

•          True

•          False

Explanation: Alveoli are tiny, thin-walled air sacs surrounded by capillaries where oxygen diffuses into the blood and carbon dioxide diffuses out, making them the functional site of gas exchange in the lungs.

Question 4: Which part of the nephron is primarily responsible for filtering blood?

•          Loop of Henle

•          Glomerulus

•          Collecting duct

•          Distal convoluted tubule

Explanation: The glomerulus is a cluster of capillaries within the nephron where blood pressure forces water, ions, and small molecules out of the blood and into the surrounding Bowman's capsule as filtrate.

Question 5: Which endocrine gland is often referred to as the "master gland"?

•          Thyroid gland

•          Adrenal gland

•          Pituitary gland

•          Pancreas

Explanation: The pituitary gland is called the master gland because it secretes hormones that regulate the activity of many other endocrine glands throughout the body, coordinating overall hormonal balance.

Question 6: Neurons transmit electrical impulses primarily along which structure?

•          Dendrite

•          Axon

•          Synapse

•          Cell body

Explanation: The axon is a long, slender projection that conducts electrical impulses, known as action potentials, away from the neuron's cell body toward the synapse to communicate with other cells.

Question 7: Peristalsis refers to involuntary wave-like muscle contractions that move food through the digestive tract.

•          True

•          False

Explanation: Peristalsis is a series of coordinated, involuntary contractions and relaxations of smooth muscle in the digestive tract wall that propel food and waste material along the esophagus and intestines.

Question 8: Which blood cells are primarily responsible for oxygen transport?

•          Leukocytes

•          Erythrocytes

•          Platelets

•          Plasma proteins

Explanation: Erythrocytes, or red blood cells, contain hemoglobin, an iron-rich protein that binds oxygen in the lungs and releases it to tissues throughout the body during systemic circulation.

Question 9: Which type of joint allows the greatest range of motion, as found in the shoulder?

•          Hinge joint

•          Pivot joint

•          Ball-and-socket joint

•          Gliding joint

Explanation: Ball-and-socket joints, such as the shoulder and hip, allow rotational movement in multiple planes because a rounded bone end fits into a cup-like socket, permitting the widest range of motion of any joint type.

Question 10: What is the function of insulin in regulating blood glucose?

•          It raises blood glucose by stimulating glycogen breakdown

•          It lowers blood glucose by promoting cellular uptake and storage

•          It has no effect on blood glucose

•          It converts glucose directly into fatty acids only in the liver

Explanation: Insulin, secreted by the pancreatic beta cells, lowers blood glucose levels by promoting the uptake of glucose into muscle and fat cells and stimulating the liver to store excess glucose as glycogen.

Question 11: The autonomic nervous system controls involuntary functions such as heart rate and digestion.

•          True

•          False

Explanation: The autonomic nervous system regulates involuntary bodily functions, including heart rate, digestion, and respiratory rate, through its sympathetic and parasympathetic divisions, without requiring conscious control.

Question 12: Which skin layer contains hair follicles, sweat glands, and blood vessels?

•          Epidermis

•          Dermis

•          Hypodermis

•          Stratum corneum

Explanation: The dermis lies beneath the epidermis and houses structures such as hair follicles, sweat glands, sebaceous glands, and blood vessels, providing structural support and vital nutrients to the skin.

Question 13: Which lung structure branches from the bronchi and leads to the alveoli?

•          Trachea

•          Bronchioles

•          Larynx

•          Pharynx

Explanation: Bronchioles are progressively narrower airway branches that extend from the bronchi and ultimately terminate in clusters of alveoli, where gas exchange occurs.

Question 14: The femur is the longest and strongest bone in the human body.

•          True

•          False

Explanation: The femur, or thighbone, is both the longest and strongest bone in the human skeleton, designed to bear substantial weight and mechanical stress during standing, walking, and running.

Question 15: Which hormone is primarily responsible for triggering the "fight or flight" response?

•          Insulin

•          Adrenaline (epinephrine)

•          Melatonin

•          Thyroxine

Explanation: Adrenaline, released by the adrenal medulla in response to stress or danger, rapidly increases heart rate, blood flow to muscles, and glucose availability to prepare the body for immediate physical action.

Question 16: What is the primary role of white blood cells (leukocytes)?

•          Carrying oxygen

•          Clotting blood

•          Defending the body against infection

•          Regulating blood pH

Explanation: Leukocytes are key components of the immune system, identifying and destroying pathogens such as bacteria and viruses through processes including phagocytosis and antibody production.

Question 17: Which structure connects muscle to bone?

•          Ligament

•          Tendon

•          Cartilage

•          Fascia

Explanation: Tendons are tough, fibrous connective tissue bands that attach skeletal muscles to bones, transmitting the force generated by muscle contraction to produce movement at a joint.

Question 18: Homeostasis refers to the body's ability to maintain a stable internal environment despite external changes.

•          True

•          False

Explanation: Homeostasis is the process by which physiological systems, such as temperature regulation and blood glucose control, work together through feedback mechanisms to keep the internal environment relatively constant.

Question 19: Which part of the brain is primarily responsible for coordinating balance and voluntary muscle movement?

•          Cerebrum

•          Cerebellum

•          Medulla oblongata

•          Hypothalamus

Explanation: The cerebellum fine-tunes motor commands from the cerebrum, coordinating balance, posture, and the precision and timing of voluntary muscle movements.

Question 20: Which structure prevents food from entering the trachea during swallowing?

•          Uvula

•          Epiglottis

•          Larynx

•          Esophageal sphincter

Explanation: The epiglottis is a flap of cartilage that folds down over the trachea during swallowing, directing food and liquid into the esophagus and preventing aspiration into the airway.

Question 21: Antibodies are produced by which type of white blood cell?

•          Neutrophils

•          B lymphocytes (B cells)

•          Red blood cells

•          Platelets

Explanation: B lymphocytes differentiate into plasma cells upon activation, which then produce and secrete antibodies specifically targeted to neutralize a particular antigen, forming a key part of the adaptive immune response.

Question 22: Which vessels carry blood away from the heart?

•          Veins

•          Arteries

•          Capillaries

•          Venules

Explanation: Arteries carry oxygenated blood away from the heart to body tissues (with the exception of the pulmonary artery), and their thick, elastic walls withstand the high pressure generated by each heartbeat.

Question 23: The pancreas functions solely as an endocrine gland.

•          True

•          False

Explanation: The pancreas is both an endocrine gland, secreting hormones like insulin and glucagon directly into the blood, and an exocrine gland, secreting digestive enzymes into the small intestine via ducts.

Question 24: Which cranial structure protects the brain?

•          Vertebrae

•          Cranium (skull)

•          Sternum

•          Pelvis

Explanation: The cranium is the rigid, bony structure that encloses and protects the brain from mechanical injury while also providing attachment points for muscles of the head and neck.

Question 25: Which muscle is the primary muscle used for breathing?

•          Diaphragm

•          Bicep

•          Trapezius

•          Deltoid

Explanation: The diaphragm is a dome-shaped skeletal muscle beneath the lungs that contracts and flattens during inhalation, expanding the thoracic cavity and drawing air into the lungs.

Question 26: Synovial fluid reduces friction between bones at a joint.

•          True

•          False

Explanation: Synovial fluid, secreted by the synovial membrane lining a joint capsule, lubricates the joint surfaces, reducing friction between the articulating bones and helping to nourish the cartilage.

Question 27: Which organ is primarily responsible for detoxifying harmful substances in the blood?

•          Kidney

•          Liver

•          Spleen

•          Gallbladder

Explanation: The liver filters blood arriving from the digestive tract, metabolizing drugs, alcohol, and other toxins into less harmful substances that can then be excreted from the body.

Question 28: Which type of immunity is gained through vaccination?

•          Natural passive immunity

•          Artificial active immunity

•          Natural active immunity

•          Artificial passive immunity

Explanation: Vaccination introduces a weakened, inactivated, or partial pathogen to stimulate the immune system to produce its own antibodies and memory cells, providing artificial active immunity without causing full-blown disease.

Question 29: The small intestine is the primary site of nutrient absorption in the digestive tract.

•          True

•          False

Explanation: The small intestine's inner surface is covered with finger-like projections called villi and microvilli that greatly increase surface area, making it the primary site where digested nutrients are absorbed into the bloodstream.

Question 30: Which structure in the ear is responsible for converting sound vibrations into neural signals?

•          Eardrum (tympanic membrane)

•          Cochlea

•          Eustachian tube

•          Ossicles

Explanation: The cochlea, a fluid-filled spiral structure in the inner ear, contains hair cells that convert mechanical sound vibrations into electrical nerve impulses, which are then transmitted to the brain via the auditory nerve.