memory b cells and memory t cells are crucial for immunological memory how does immunological memory enhance the immune response upon re exposure to a

ATI TEAS 7

TEAS version 7 quizlet science

1. Memory B cells and memory T cells are crucial for immunological memory. How does immunological memory enhance the immune response upon re-exposure to a pathogen?

A. It increases the production of the same ineffective antibodies.
B. It allows for a quicker and more robust immune response.
C. It suppresses the immune system to prevent overreaction.
D. It triggers a completely different immune response.

Correct answer: B

Rationale: Immunological memory enhances the immune response upon re-exposure to a pathogen by allowing for a quicker and more robust immune response. Memory B cells and memory T cells are primed to recognize the pathogen quickly and mount a faster and more effective response, leading to a more efficient clearance of the pathogen. Choice A is incorrect because immunological memory does not increase the production of ineffective antibodies but rather promotes the production of specific antibodies that are effective against the pathogen. Choice C is incorrect as immunological memory does not suppress the immune system; instead, it enhances the response. Choice D is incorrect because immunological memory leads to a recall of the specific immune response mounted during the initial exposure, not a completely different response.

2. What is the difference between homologous chromosomes and sister chromatids?

A. Homologous chromosomes have the same genes but may have different alleles, while sister chromatids are identical copies of the same chromosome.
B. Homologous chromosomes are only found in diploid cells, while sister chromatids are found in both haploid and diploid cells.
C. Both homologous chromosomes and sister chromatids are genetically identical, but only sister chromatids separate during mitosis.
D. Both homologous chromosomes and sister chromatids can separate during mitosis, but only homologous chromosomes have different alleles.

Correct answer: A

Rationale: Rationale: - Homologous chromosomes are pairs of chromosomes that have the same genes in the same order, one from each parent. While they carry the same genes, they may have different alleles (variants of a gene). - Sister chromatids are exact copies of each other, formed during DNA replication. They are held together by a centromere and are produced during the S phase of the cell cycle. - During meiosis, homologous chromosomes pair up and exchange genetic material through crossing over, leading to genetic variation. Sister chromatids separate during mitosis to ensure each daughter cell receives an identical copy of the genetic material.

3. What is the function of the myelin sheath in a neuron?

A. To transmit electrical impulses
B. To insulate and speed up electrical signals
C. To produce neurotransmitters
D. To protect the neuron from damage

Correct answer: B

Rationale: The myelin sheath serves to insulate neurons and accelerate the transmission of electrical signals along the axon. This insulation helps in the efficient conduction of nerve impulses by preventing signal loss or leakage. Choice A is incorrect because the myelin sheath does not transmit electrical impulses itself but rather helps in the conduction. Choice C is incorrect as the myelin sheath is not responsible for producing neurotransmitters. Choice D is also incorrect as the primary function of the myelin sheath is not to protect the neuron from damage. Therefore, the correct answer is B, as it accurately describes the function of the myelin sheath in a neuron.

4. What is the name of the microscopic filtering unit within the kidney responsible for waste removal and blood volume regulation?

A. Nephron
B. Ureteric bud
C. Renal pyramid
D. Glomerulus

Correct answer: A

Rationale: The correct answer is A: Nephron. The nephron is the functional unit of the kidney responsible for waste removal and blood volume regulation. It is composed of several structures, including the glomerulus, Bowman's capsule, proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct. The other options mentioned in the question (ureteric bud, renal pyramid, and glomerulus) are not the correct names for the microscopic filtering unit within the kidney. The glomerulus is a part of the nephron, specifically responsible for ultrafiltration in the initial stage of urine formation.

5. Which skin condition is characterized by red, itchy, and inflamed patches?

A. Eczema
B. Psoriasis
C. Melanoma
D. Keloid

Correct answer: A

Rationale: Eczema is a skin condition characterized by red, itchy, and inflamed patches. It is a common condition that can vary in severity and often presents with symptoms such as dry, scaly skin, and sometimes oozing or crusting. Psoriasis, on the other hand, presents with red, scaly patches but is not typically described as itchy. Melanoma is a type of skin cancer characterized by the development of abnormal moles, while keloid is a type of raised scar that can occur after an injury to the skin. Therefore, the correct answer is eczema due to its specific symptom presentation of red, itchy, and inflamed patches.