Nokea
Which blood component is chiefly responsible for clotting?
- A. Platelets
- B. Red blood cells
- C. Antigens
- D. Plasma cells
Correct Answer: A
Rationale: The correct answer is A: Platelets. Platelets are small cell fragments in the blood that play a crucial role in clotting. When there is an injury, platelets adhere to the site and release chemicals that help form a clot to prevent excessive bleeding. Red blood cells transport oxygen, antigens are substances that trigger an immune response, and plasma cells are a type of white blood cell involved in producing antibodies, none of which are primarily responsible for clotting.
You may also like to solve these questions
Where does sperm maturation take place in the male reproductive system?
- A. Seminal vesicles
- B. Prostate gland
- C. Epididymis
- D. Vas Deferens
Correct Answer: C
Rationale: Sperm maturation occurs in the epididymis, a coiled tube located on the back of each testicle. In the epididymis, sperm gain motility and the ability to fertilize an egg. It serves as a storage site for mature sperm until ejaculation. The seminal vesicles and the prostate gland contribute fluids to semen, enhancing sperm viability and motility. The vas deferens is responsible for transporting mature sperm from the epididymis to the urethra during ejaculation, but it is not where sperm maturation takes place. Therefore, the correct answer is the epididymis.
In a closed system with a gas at constant volume, what will happen to the temperature if the pressure is increased?
- A. The temperature will stay the same
- B. The temperature will decrease
- C. The temperature will increase
- D. It cannot be determined with the information given
Correct Answer: C
Rationale: In a closed system with a gas at constant volume, according to Gay-Lussac's law, the temperature of a gas is directly proportional to its pressure. When the pressure is increased, the temperature of the gas will also increase. This relationship is a direct consequence of the ideal gas law, where pressure and temperature are directly proportional when volume is held constant. Therefore, as pressure increases in a closed system with constant volume, the temperature of the gas will increase. Choices A, B, and D are incorrect. The temperature will not stay the same (Choice A) or decrease (Choice B) when the pressure is increased in this scenario. The relationship between pressure and temperature in a closed system with constant volume allows for a definitive conclusion about the increase in temperature when pressure is increased, making Choice D, which suggests inability to determine, incorrect.
What is the function of the sinuses?
- A. To trap many airborne pathogens
- B. To direct air down the trachea rather than the esophagus
- C. To warm, humidify, and filter air
- D. To sweep away pathogens and direct them toward the top of the trachea
Correct Answer: C
Rationale: The correct function of the sinuses is to warm, humidify, and filter the air we breathe. Sinuses play a crucial role in preparing the air for the respiratory system by adding moisture, warmth, and filtering out particles. Choice A is incorrect because while sinuses can help filter some particles, their primary function is not to trap pathogens. Choice B is incorrect as the sinuses do not control the direction of air down the trachea; this is regulated by the epiglottis and vocal cords. Choice D is incorrect as sinuses do not sweep pathogens away or direct them towards the trachea; instead, they condition the air for respiration.
How many neurons typically comprise a sensory pathway?
- A. 1
- B. 2
- C. 3
- D. 4
Correct Answer: C
Rationale: A sensory pathway generally consists of three neurons: a first-order neuron, a second-order neuron, and a third-order neuron. The first-order neuron carries sensory information from the periphery to the spinal cord or brainstem. The second-order neuron then transmits this information to the thalamus or cerebellum. Finally, the third-order neuron projects the sensory input to the cerebral cortex for processing and perception. Therefore, the correct answer is 3 (C). Choices A, B, and D are incorrect as they do not align with the typical structure of a sensory pathway involving three neurons.
What is one feature that both prokaryotes and eukaryotes have in common?
- A. A plasma membrane
- B. A nucleus enclosed by a membrane
- C. Organelles
- D. A nucleoid
Correct Answer: A
Rationale: The correct answer is A: A plasma membrane. Both prokaryotes and eukaryotes share the characteristic of having a plasma membrane that surrounds the cell. While eukaryotes also possess a nucleus enclosed by a membrane and various organelles, prokaryotes lack a nucleus and membrane-bound organelles. The plasma membrane, however, is a universal feature found in all cells, regardless of their classification as prokaryotic or eukaryotic. Choice B is incorrect because only eukaryotes have a nucleus enclosed by a membrane. Choice C is incorrect because prokaryotes have limited organelles compared to eukaryotes. Choice D is incorrect as a nucleoid is a region in prokaryotic cells where the genetic material is located, not a common feature shared with eukaryotes.