which of the following choices would contain the code for making a protein

ATI TEAS 7

TEAS 7 Science Practice Test

1. Which of the following choices would contain the code for making a protein?

A. mRNA
B. tRNA
C. rRNA
D. DNA polymerase

Correct answer: A

Rationale: The correct answer is A: mRNA (messenger RNA). mRNA contains the genetic code or instructions for making a protein. During protein synthesis, mRNA carries the genetic information from DNA in the cell nucleus to the ribosomes, where proteins are synthesized. The sequence of nucleotides in mRNA corresponds to the sequence of amino acids that will be used to build the protein. Choice B, tRNA (transfer RNA), is involved in carrying amino acids to the ribosome during protein synthesis but does not contain the code for making a protein. Choice C, rRNA (ribosomal RNA), is a component of ribosomes where protein synthesis occurs but does not contain the specific code for making a protein. Choice D, DNA polymerase, is an enzyme involved in DNA replication, not in directly coding for protein synthesis.

2. What is the function of the pericardium, the sac surrounding the heart?

A. To generate electrical impulses for heart contraction
B. To transport blood throughout the body
C. To provide lubrication for heart movement
D. To protect the heart and anchor it in place

Correct answer: C

Rationale: The pericardium is a double-walled sac that surrounds the heart and contains a small amount of fluid to provide lubrication for the movement of the heart within the chest cavity. It helps reduce friction as the heart beats and moves. Choice A is incorrect because the generation of electrical impulses for heart contraction is primarily the function of the heart's specialized conduction system. Choice B is incorrect as the pericardium is not involved in the transportation of blood throughout the body. Choice D is also incorrect as while the pericardium does protect the heart, its primary function is to provide lubrication and reduce friction.

3. What is the protective fluid that surrounds the brain and spinal cord?

A. Blood
B. Cerebrospinal fluid
C. Myelin sheath
D. Insulin

Correct answer: B

Rationale: Cerebrospinal fluid is the protective fluid that surrounds the brain and spinal cord. It acts as a cushion to protect these vital organs from injury and provides nutrients and removes waste products. Blood, myelin sheath, and insulin do not serve as the protective fluid surrounding the brain and spinal cord. Blood carries nutrients and oxygen to cells, myelin sheath is a protective covering of nerve fibers, and insulin is a hormone involved in regulating blood sugar levels.

4. Which structure in the respiratory system is responsible for the exchange of oxygen and carbon dioxide between the lungs and the bloodstream?

A. Trachea
B. Bronchi
C. Alveoli
D. Bronchioles

Correct answer: C

Rationale: The alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide occurs. Oxygen from the air diffuses into the bloodstream through the alveoli, while carbon dioxide from the bloodstream diffuses into the alveoli to be exhaled. The trachea, bronchi, and bronchioles are essential parts of the airway system responsible for transporting air to and from the lungs but do not directly participate in the gas exchange process. Therefore, option C, the alveoli, is the correct answer for the structure responsible for the exchange of oxygen and carbon dioxide between the lungs and the bloodstream.

5. Which of the following is an example of a commensal relationship between a microorganism and a human?

A. Salmonella causing food poisoning
B. taphylococcus aureus causing skin infections
C. coli living in the gut
D. Rabies virus causing neurological disease

Correct answer: C

Rationale: A commensal relationship is a type of symbiotic relationship in which one organism benefits, while the other is neither harmed nor benefited. In this case, E. coli living in the gut is an example of a commensal relationship because it can benefit from the environment in the gut without causing harm to the human host. Option A, Salmonella causing food poisoning, is an example of a pathogenic relationship where the microorganism causes harm to the host. Option B, Staphylococcus aureus causing skin infections, is also an example of a pathogenic relationship where the microorganism causes harm to the host. Option D, Rabies virus causing neurological disease, is another example of a pathogenic relationship where the microorganism causes harm to the host.