what is the process of making copies of dna called

ATI TEAS 7

TEAS 7 practice test free science

1. What is the process of making copies of DNA called?

A. Transcription
B. Translation
C. Replication
D. DNA repair

Correct answer: C

Rationale: A) Transcription is the process of synthesizing RNA from a DNA template. It involves the creation of mRNA molecules from a DNA template. B) Translation is the process of synthesizing proteins from mRNA. During translation, the genetic code carried by mRNA is decoded to produce a specific sequence of amino acids, forming a protein. C) Replication is the process of making copies of DNA. This process occurs before cell division and ensures that each daughter cell receives an identical copy of the genetic material. D) DNA repair is a cellular mechanism that corrects errors in DNA that arise due to various factors such as exposure to mutagens or mistakes during DNA replication. It is essential for maintaining the integrity of the genetic material.

2. Where does most of the chemical digestion take place?

A. Large intestine
B. Stomach
C. Small intestine
D. Esophagus

Correct answer: C

Rationale: Most of the chemical digestion occurs in the small intestine. Enzymes in the small intestine break down nutrients into smaller molecules that can be absorbed by the body. The stomach plays a role in digestion by breaking down food mechanically and initiating some chemical digestion, but the majority of nutrient breakdown and absorption happens in the small intestine. The large intestine mainly absorbs water and salts, with little to no digestion taking place there. The esophagus is a muscular tube that helps move food from the mouth to the stomach and does not participate in digestion.

3. What is the pathway of oxygenated blood from the lungs?

A. Lungs to the left atrium, through the mitral valve into the left ventricle, pumped into the aorta upon contraction, then dispersed to tissues via a network of arteries and capillaries
B. Lungs to the right atrium, through the mitral valve into the right ventricle, pumped into the aorta upon contraction, then dispersed to tissues via a network of arteries and veins
C. Lungs to the left atrium, directly to the right aorta, then dispersed to tissues via a network of arteries and capillaries
D. Lungs to the left atrium, through the septal valve, stored in the left ventricles, then dispersed to tissues via a network of arteries and capillaries

Correct answer: A

Rationale: The correct pathway of oxygenated blood from the lungs is as follows: Oxygenated blood travels from the lungs to the left atrium, then passes through the mitral valve into the left ventricle. From there, it is pumped into the aorta upon contraction of the heart and is then dispersed to various tissues throughout the body via a network of arteries and capillaries. Choice B is incorrect as it incorrectly mentions the right atrium and ventricle, which are associated with deoxygenated blood. Choice C is incorrect as it mentions a direct connection to the right aorta, which does not exist in the circulatory system. Choice D is incorrect as it refers to the septal valve (which is not anatomically correct) and storing blood in the left ventricle, which does not occur in the normal circulation of blood.

4. What determines the defining characteristic of an element?

A. Neutrons in its nucleus
B. Electrons surrounding the nucleus
C. Protons in its nucleus
D. All of the above

Correct answer: C

Rationale: The defining characteristic of an element is determined by the number of protons in its nucleus, which is referred to as the atomic number. The number of protons uniquely identifies an element. The correct answer is choice C because the number of protons in the nucleus of an atom defines its elemental identity, as different elements have a unique number of protons. Neutrons and electrons do play essential roles in the atom, but they do not determine the defining characteristic of an element. Neutrons contribute to the stability of the nucleus and isotopes of an element, while electrons are involved in chemical bonding and the reactivity of an atom.

5. What is a major structure of the limbic system?

A. Brainstem
B. Spinal cord
C. Hypothalamus
D. Cerebral cortex

Correct answer: C

Rationale: The correct answer is C: Hypothalamus. The hypothalamus is a significant structure of the limbic system responsible for regulating various functions such as emotions, autonomic functions, and hormone production. It plays a crucial role in maintaining homeostasis and orchestrating responses to stress and emotional stimuli. Choices A, B, and D are incorrect. The brainstem, although a vital part of the brain, is not a major structure of the limbic system. The spinal cord is not part of the limbic system; it is primarily involved in transmitting sensory and motor information between the brain and the rest of the body. The cerebral cortex is responsible for higher cognitive functions but is not a major structure within the limbic system.