Question 1

Which of the following is the primary function of hemoglobin in the human body?

Accepted Answer

Hemoglobin is an iron-containing protein in red blood cells that binds to oxygen in the lungs and transports it to tissues throughout the body. It also carries carbon dioxide back to the lungs for exhalation.

Question 2

Vitamin C is essential for the synthesis of which protein in the human body?

Accepted Answer

Vitamin C (ascorbic acid) is a cofactor for enzymes that stabilize and cross-link collagen, the most abundant protein in the human body. Collagen provides structural support to skin, bones, tendons, and blood vessels.

Question 3

Which of the following hormones is produced by the pancreas and regulates blood glucose levels?

Accepted Answer

The pancreas produces insulin, which is secreted by beta cells in the islets of Langerhans. Insulin lowers blood glucose by promoting glucose uptake in cells and its storage as glycogen. Glucagon, also produced by the pancreas (alpha cells), raises blood glucose when it is low.

Question 4

Which of the following is the correct sequence of blood flow through the human heart?

Accepted Answer

Deoxygenated blood from the body enters the right atrium via the superior and inferior vena cava. It flows to the right ventricle, which pumps it to the lungs via the pulmonary artery. Oxygenated blood returns from the lungs via the pulmonary veins to the left atrium, flows to the left ventricle, and is pumped to the body via the aorta.

Question 5

The enzyme responsible for breaking down starch into glucose in the human digestive system is:

Accepted Answer

Amylase is the enzyme that catalyzes the hydrolysis of starch (a polysaccharide) into maltose and glucose (simple sugars). Salivary amylase begins this process in the mouth, and pancreatic amylase continues it in the small intestine.

Question 6

Vitamin C deficiency in the human body leads to which disease?

Accepted Answer

Vitamin C (ascorbic acid) is essential for collagen synthesis, immune function, and iron absorption. Its deficiency causes scurvy, characterized by bleeding gums, poor wound healing, and weakened connective tissues.

Question 7

Which part of the human body produces insulin?

Accepted Answer

Insulin is a hormone produced by the beta cells of the islets of Langerhans in the pancreas. It regulates blood glucose levels. Deficiency of insulin leads to diabetes mellitus.

Question 8

Which of the following vitamins is synthesized by the human body and does NOT need to be obtained from external dietary sources?

Accepted Answer

Vitamin D is synthesized by the human body when skin is exposed to sunlight (UV-B radiation). The 7-dehydrocholesterol in the skin converts to previtamin D3, which is then converted to active vitamin D in the liver and kidneys. While small amounts may be obtained from diet (fatty fish, egg yolks, fortified milk), the body can produce sufficient amounts endogenously. All other vitamins (A, B-complex, C, E, K) must be obtained from dietary sources as the human body cannot synthesize them.

Question 9

Which of the following glands secretes insulin in the human body?

Accepted Answer

The pancreas is an endocrine gland that contains clusters of cells called islets of Langerhans. Beta cells (β-cells) within these islets secrete insulin, a hormone that regulates blood glucose levels.

Question 10

How many chambers does the human heart have?

Accepted Answer

The human heart is a four-chambered organ consisting of two upper chambers (atria) and two lower chambers (ventricles). The right atrium receives deoxygenated blood from the body, the right ventricle pumps it to the lungs, the left atrium receives oxygenated blood from the lungs, and the left ventricle pumps it to the body.

Question 11

Which of the following is the primary function of haemoglobin in the human body?

Accepted Answer

Haemoglobin is an iron-containing protein in red blood cells that binds to oxygen in the lungs and transports it to tissues throughout the body. It also carries carbon dioxide back to the lungs for exhalation.

Question 12

Which part of the human brain is primarily responsible for maintaining balance and coordination of body movements?

Accepted Answer

The cerebellum, located at the back of the brain, is primarily responsible for coordinating voluntary movements, balance, and fine motor control. The cerebrum handles higher functions, the medulla oblongata controls autonomic functions, and the hypothalamus regulates body temperature and hormones.

Question 13

The hormone insulin is produced by which type of cell in the pancreas?

Accepted Answer

Insulin is produced by beta (β) cells located in the islets of Langerhans within the pancreas. These cells secrete insulin in response to elevated blood glucose levels to regulate blood sugar homeostasis.

Question 14

Which of the following statements about the human kidney is correct?

Accepted Answer

The human kidney filters blood to produce urine through three main processes: glomerular filtration (in Bowman's capsule), selective reabsorption (in proximal convoluted tubule), and secretion (in distal convoluted tubule and collecting duct). Each kidney contains approximately 1 million nephrons.

Question 15

The human skeleton serves multiple functions. Which of the following is NOT a primary function of the skeletal system?

Accepted Answer

The primary functions of the skeletal system are: (1) support and structure, (2) protection of organs, (3) movement (with muscles), (4) mineral storage (calcium and phosphorus), and (5) blood cell production (in bone marrow). Hormone production is not a primary skeletal function.

Question 16

Which of the following hormones is primarily responsible for regulating blood glucose levels by promoting the uptake of glucose into cells?

Accepted Answer

Insulin is a hormone secreted by the beta cells of the pancreatic islets (Islets of Langerhans). It lowers blood glucose by facilitating glucose uptake into muscle, fat, and liver cells, and promoting glycogen synthesis. This is a fundamental mechanism of glucose homeostasis.

Question 17

Which of the following is the primary function of the small intestine in the human digestive system?

Accepted Answer

The small intestine (duodenum, jejunum, and ileum) is the primary site of nutrient absorption. It receives partially digested food (chyme) from the stomach and secretions from the pancreas and liver, where chemical digestion is completed and nutrients are absorbed into the bloodstream.

Question 18

The human heart has four chambers. Which chamber receives oxygenated blood from the lungs?

Accepted Answer

The left atrium receives oxygenated blood from the lungs via the pulmonary veins. This blood is then pumped into the left ventricle, which distributes it to the body via the aorta.

Question 19

Vitamin B12 deficiency in the human body primarily leads to which of the following conditions?

Accepted Answer

Vitamin B12 (cobalamin) is essential for DNA synthesis and myelin formation in nerve cells. Its deficiency causes pernicious anemia (megaloblastic anemia) and can lead to neurological complications if untreated.

Question 20

Which of the following blood groups is considered the universal donor in blood transfusion?

Accepted Answer

Blood group O negative (O−) is the universal donor because it lacks both A and B antigens and the Rh antigen on the surface of red blood cells. This means it will not trigger an immune response in recipients of any blood group.

SSC CGL Biology — Human Body

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Biology — Human Body — Practice Questions

60-Second Revision — Biology — Human Body