Nokea
What is a primary function of red blood cells?
- A. To fight infection
- B. To carry oxygen
- C. To produce antibodies
- D. To transport waste
Correct Answer: B
Rationale: The main function of red blood cells is to carry oxygen from the lungs to all the body's tissues and organs, where it is needed for cellular functions and metabolism. This process is essential for sustaining life and providing energy to cells. Choice A is incorrect because fighting infection is primarily done by white blood cells. Choice C is incorrect because antibody production is mainly carried out by specialized white blood cells. Choice D is incorrect as the primary role of red blood cells is not to transport waste, but rather to transport oxygen and some carbon dioxide.
You may also like to solve these questions
What is the term for a microorganism that lives on or in the human body and normally causes no disease or harm?
- A. Bacteria
- B. Commensal Microorganism
- C. Microorganism
- D. Host
Correct Answer: B
Rationale: The correct term for a microorganism that lives on or in the human body without causing harm is a commensal microorganism. Commensal microorganisms coexist with the host without causing disease or harm. Choice A, 'Bacteria,' is too broad as not all bacteria are harmless in the body. Choice C, 'Microorganism,' is a general term and does not specifically refer to the harmless nature of the organism. Choice D, 'Host,' refers to the organism harboring the microorganism, not the microorganism itself.
Which of the following statements regarding the working of the heart is not correct?
- A. The atria contract, and the valves open to allow blood into the ventricles.
- B. The heartbeat begins when the heart muscles relax, and blood flows into the atria.
- C. The valves close to stop blood from flowing backward.
- D. The ventricles contract, forcing blood to leave the heart.
Correct Answer: B
Rationale: The correct answer is B because the heartbeat actually begins when the heart muscles relax, allowing the chambers to fill with blood. The contraction phase follows, which propels blood out of the heart. The other statements are accurate in describing the normal sequence of events in the heart's functioning: the atria contract to push blood into the ventricles, the valves close to prevent backflow of blood, and the ventricles contract to pump blood out of the heart.
Which of the following describes the term allele?
- A. A specific form of a gene that can exist at a particular locus
- B. An inheritable variation of a gene
- C. A grouping of various genes
- D. Variations of complementary base pairs
Correct Answer: B
Rationale: The correct answer is B. Alleles are different forms of a gene that can exist at a specific locus. They represent variations of a gene and are inheritable. Choice A is incorrect as it does not fully capture the concept of an allele, which is a specific form of a gene rather than a substitution. Choice C is incorrect as alleles are not a grouping of various genes but rather different forms of a single gene at a specific locus. Choice D is also incorrect as it does not accurately describe alleles; alleles are variations of genes, not base pairs.
Where does glycolysis occur within the cell?
- A. Cytosol
- B. Nucleus
- C. Mitochondria
- D. Endoplasmic reticulum
Correct Answer: A
Rationale: Glycolysis occurs in the cytosol, the liquid component of the cytoplasm, not in the nucleus, mitochondria, or endoplasmic reticulum. It is the initial step in cellular respiration and involves the breakdown of glucose into pyruvic acid. The process takes place in the cytosol as it does not require membrane-bound organelles like the mitochondria or endoplasmic reticulum for its completion.
What is the primary function of the stomach in the digestive system?
- A. To absorb nutrients
- B. To break down proteins
- C. To neutralize stomach acid
- D. To regulate body temperature
Correct Answer: B
Rationale: The correct answer is B: 'To break down proteins.' The primary function of the stomach in the digestive system is to break down proteins using gastric acid and enzymes. The stomach's acidic environment aids in protein digestion and prepares food for further processing in the small intestine. Choice A is incorrect because nutrient absorption primarily occurs in the small intestine, not the stomach. Choice C is incorrect because the stomach actually produces stomach acid to aid in digestion, not to neutralize it. Choice D is incorrect because regulating body temperature is not a primary function of the stomach within the digestive system.