Science

Science Related

Review Science related questions and content

What process causes most of the carbon dioxide from the blood to move into alveoli?

  • A. Active transport
  • B. Diffusion down a concentration gradient
  • C. Passive transport using carrier proteins
  • D. Conversion to carbon monoxide
Correct Answer: B

Rationale: The correct answer is B: Diffusion down a concentration gradient. In the alveoli, there is a higher concentration of carbon dioxide in the blood compared to the air, leading to the movement of carbon dioxide from the blood into the alveoli through diffusion. This natural movement occurs due to the concentration gradient, ensuring the elimination of carbon dioxide during respiration. Active transport, a process requiring energy, is not involved in this movement. Passive transport using carrier proteins is not the primary mechanism for carbon dioxide movement in the lungs. Conversion to carbon monoxide is incorrect as it does not explain the physiological process of carbon dioxide exchange in the alveoli.

You may also like to solve these questions

Which structure of the female reproductive system is the source of the blood and mucosal tissue during menstruation?

  • A. Fallopian Tubes
  • B. Endometrium
  • C. Cervix
  • D. Ovaries
Correct Answer: B

Rationale: The correct answer is B: Endometrium. The endometrium is the inner lining of the uterus where an embryo implants during pregnancy. If no pregnancy occurs, the endometrial lining sheds during menstruation, leading to the discharge of blood and mucosal tissue. The fallopian tubes are responsible for transporting the egg from the ovary to the uterus. The cervix is the lower part of the uterus that connects to the vagina. The ovaries produce eggs and hormones, but they are not the source of blood and mucosal tissue during menstruation.

Which of the following processes causes most of the carbon dioxide from the blood to move into the alveoli?

  • A. Diffusion down a concentration gradient
  • B. Active transport using energy or passive transport using carrier proteins
  • C. Conversion to carbon monoxide
  • D. Conversion to carbon dioxide
Correct Answer: A

Rationale: The correct answer is A: Diffusion down a concentration gradient. In the alveoli, carbon dioxide moves from an area of higher concentration in the blood to an area of lower concentration in the alveolar air sacs. This movement occurs through simple diffusion, which does not require energy or carrier proteins. Active transport (B) requires energy input from the cell, while conversion to carbon monoxide (C) or conversion to carbon dioxide (D) are not processes involved in the movement of carbon dioxide from the blood to the alveoli.

What is the primary outcome of using a catalyst in a chemical reaction?

  • A. A greater amount of heat energy is released during the reaction
  • B. The yield of the product remains consistent
  • C. The reaction is accelerated and completed in a shorter timeframe
  • D. A different product is often formed
Correct Answer: C

Rationale: The primary outcome of using a catalyst in a chemical reaction is to accelerate the reaction and complete it in a shorter timeframe. A catalyst functions by lowering the activation energy required for the reaction to occur, thereby speeding up the process without altering the amount of heat energy released, the yield of the product, or the nature of the final product. This acceleration makes the reaction more efficient by facilitating the conversion of reactants to products in a more rapid manner.

Which of the following processes uses an electrochemical gradient to produce ATP?

  • A. Chemiosmosis
  • B. Cell division
  • C. Fermentation
  • D. Photosynthesis
Correct Answer: A

Rationale: Chemiosmosis is the process where ATP is produced as protons flow down their electrochemical gradient across a membrane, typically during cellular respiration or photosynthesis. Cell division and fermentation do not produce ATP via an electrochemical gradient.

Which of the following substances is excreted by the sweat glands in response to the breakdown of proteins and the formation of ammonia?

  • A. Lysozymes
  • B. Water
  • C. Urea
  • D. Sebum
Correct Answer: C

Rationale: The correct answer is Urea. Sweat glands excrete urea in response to the breakdown of proteins and the formation of ammonia. Urea is a waste product formed in the liver by the breakdown of amino acids. It is then excreted by the kidneys in urine and by sweat glands through perspiration. Urea plays a vital role in the excretory process by helping eliminate nitrogenous wastes from the body and maintaining proper physiological balance.

Copyright © 2025 Nokea. All rights reserved.