31. What are the cells involved in innate immunity?
[A] Phagocytes
[B] Macrophages
[C] Natural Killer Cells
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Innate immune cells are white blood cells. It mediates innate immunity and includes basophils, dendritic cells, eosinophils, Langerhans cells, mast cells, monocytes and macrophages, neutrophils and NK cells.
32. Which of the following immunity is called the first line of defense?
[A] Innate Immunity
[B] Active immunity
[C] Passive immunity
[D] Acquired immunity
Show Answer
Correct Answer: A [Innate Immunity]
Notes:
Innate Immunity is called the first line of defense. Innate immune cells are white blood cells that mediate innate immunity and include basophils, dendritic cells, eosinophils, Langerhans cells, mast cells, monocytes and macrophages, neutrophils, and NK cells.
33. How does food move through your digestive tract?
[A] By gravity
[B] By wavelike muscle contractions
[C] By cilia
[D] By chemical absorption
Show Answer
Correct Answer: B [By wavelike muscle contractions]
Notes:
Food moves through your digestive system by wave-like muscle contractions.
34. Gastroesophageal reflux disease is related to which of the following?
[A] circulatory system
[B] digestive system
[C] respiratory system
[D] excretory system
Show Answer
Correct Answer: B [digestive system]
Notes:
Gastroesophageal reflux disease is related to the digestive system. Gastroesophageal reflux disease (GERD) occurs when stomach acid repeatedly backs up into the tube connecting your mouth and stomach (esophagus).
35. Lassa and Ebola are emergent viruses in W. Africa. What is their origin?
[A] Humans
[B] Primates
[C] Fruit bats
[D] Pigs
Show Answer
Correct Answer: C [Fruit bats]
Notes:
Lassa and Ebola are emergent viruses in W. Africa originated by Fruit bats. Ebola hemorrhagic fever is caused by Ebola virus infection.
36. Which protein helps in DNA winding?
[A] Helicase
[B] Histone
[C] Lipase
[D] Cellulase
Show Answer
Correct Answer: B [Histone]
Notes:
A protein that provides structural support to a chromosome is called histone.
37. Gastric juice has a pH of about ____:
[A] 1.5 to 3.5
[B] 5 to 6
[C] 6 to 8
[D] 8.5 to 9.5
Show Answer
Correct Answer: A [1.5 to 3.5]
Notes:
Gastric acid, also known as gastric juice or stomach acid, is a digestive fluid, formed in the stomach. It is composed of hydrochloric acid (HCl), potassium chloride (KCl) and sodium chloride (NaCl). It is strongly acidic with pH varying from 1.5 to 3.5. the acid plays a key role in digestion of proteins.
38. ___ is the study of the physical form and external structure of plants:
[A] Physiology
[B] Anatomy
[C] Phytomorphology
[D] Cytology
Show Answer
Correct Answer: C [Phytomorphology]
Notes:
Plant morphology or phytomorphology is the study of the physical form and external structure of plants. This is usually considered distinct from plant anatomy, which is the study of the internal structure of plants, especially at the microscopic level. It is useful in the visual identification of plants.
39. Activity of an enzyme can be modulated by change of
____:
[A] pH
[B] Light
[C] Humidity
[D] Rainfall
Show Answer
Correct Answer: A [pH]
Notes:
Changes in pH which can accompany metabolic process such as respiration (aerobic glycolysis for example) can alter the conformation of an enzyme and hence enzyme activity such as salivarya mylase is effective in neutral condition, pepsin in acidic condition l.5 (less than pH 7) and trypsin in basic condition (more than pH 7).
40. With regard to kidneys and its functions, which of the following statements is not correct?
[A] Each nephron has two parts – the glomerulus and the renal tubule
[B] They maintain water balance and expel metabolic waste
[C] Their basic functional units are called nephrons
[D] Reptiles have relatively more nephrons than birds
Show Answer
Correct Answer: D [Reptiles have relatively more nephrons than birds]
Notes:
The kidneys perform many crucial functions, including: maintaining overall fluid balance. regulating and filtering minerals from blood. filtering waste materials from food, medications, and toxic substances. The renal corpuscle of each kidney nephron has two parts – they are the Glomerulus, which is a network of small blood vessels called capillaries, and the Bowman’s Capsule (also known as the Glomerular Capsule), which is the double-walled epithelial cup within which the glomerulus is contained. A nephron is the basic structural and functional unit of the kidney. They are the microscopic structure composed of a renal corpuscle and a renal tubule. The word nephron is derived from the Greek word – nephros, meaning kidney. There are about millions of nephrons in each human kidney.
