unlike the circulatory system the lymphatic system does not have a pump how does lymph move through the lymphatic vessels

ATI TEAS 7

TEAS 7 science practice

1. Unlike the circulatory system, the lymphatic system does not have a pump. How does lymph move through the lymphatic vessels?

A. By the pumping action of the heart
B. Due to muscle contractions and breathing movements
C. Through one-way valves within the vessels
D. All of the above

Correct answer: C

Rationale: Lymph moves through the lymphatic vessels primarily due to muscle contractions and breathing movements and also with the help of one-way valves within the vessels. The lymphatic system lacks a central pump like the heart; hence, it relies on the contraction of surrounding muscles and breathing movements to propel lymph fluid. One-way valves within the lymphatic vessels prevent backflow and ensure the unidirectional flow of lymph. Option A is incorrect as the lymphatic system does not rely on the pumping action of the heart. Option D is incorrect as the correct answer is the combination of muscle contractions, breathing movements, and one-way valves, not all the options provided.

2. Which of the following correctly lists the normal blood flow through the heart?

A. Left ventricle, left atrium, body, right ventricle, right atrium, lungs
B. Left atrium, left ventricle, lungs, right atrium, right ventricle, body
C. Right atrium, right ventricle, lungs, left atrium, left ventricle, body
D. Right ventricle, right atrium, body, left atrium, left ventricle, lungs

Correct answer: B

Rationale: The correct order of normal blood flow through the heart is as follows: from the body, blood flows into the right atrium, then to the right ventricle, followed by the lungs through the pulmonary artery for oxygenation. Oxygenated blood then returns to the heart through the pulmonary veins into the left atrium, then moves into the left ventricle before being pumped out to the body. Choice B correctly depicts this sequential flow of blood through the heart. Choices A, C, and D are incorrect as they do not follow the typical path of blood flow through the heart.

3. What is the first number in a blood pressure reading?

A. Diastolic pressure
B. Mean arterial pressure
C. Pulse rate
D. Systolic pressure

Correct answer: D

Rationale: The correct answer is D: Systolic pressure. In a blood pressure reading, the first number represents the systolic pressure, which is the maximum pressure in the arteries during heart contraction. The second number in the reading is the diastolic pressure, which indicates the pressure in the arteries when the heart is at rest. Choices A, B, and C are incorrect because diastolic pressure, mean arterial pressure, and pulse rate are not the first numbers in a blood pressure reading.

4. 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.

5. Which of the following organs is responsible for filtering waste from the blood?

A. Liver
B. Kidneys
C. Pancreas
D. Heart

Correct answer: B

Rationale: The correct answer is B: Kidneys. The kidneys play a vital role in filtering waste from the blood, regulating fluid and electrolyte balance in the body. The liver is involved in detoxification and metabolism, while the pancreas aids in digestion and blood sugar regulation. The heart is responsible for pumping blood throughout the body and does not directly filter waste from the blood.