ati teas 7 science

Correct Answer: D

Rationale: The correct answer is D, Collagen. Collagen is a fibrous protein known for its structural role in connective tissues. It has a triple helix structure, providing strength and support to tissues. Insulin (A) is a hormone, not a fibrous protein. Keratin (B) is a structural protein found in hair and nails. Hemoglobin (C) is a globular protein responsible for oxygen transport in red blood cells. Therefore, collagen is the only fibrous protein among the choices.

Correct Answer: B

Rationale: The correct answer is B: Pulmonary artery. The pulmonary artery carries deoxygenated blood from the heart to the lungs for oxygenation. This is a crucial step in the pulmonary circulation system. The pulmonary vein carries oxygenated blood from the lungs back to the heart, so it does not transport blood from the heart to the lungs. The aorta is responsible for carrying oxygenated blood from the heart to the rest of the body, not to the lungs. The superior vena cava is a large vein that carries deoxygenated blood from the upper body to the heart, not to the lungs. Therefore, the pulmonary artery is the correct choice for transporting blood from the heart to the lungs.

Correct Answer: D

Rationale: The correct answer is D, both transcription and translation. First, DNA undergoes transcription to produce mRNA, which carries the genetic information. Then, during translation, mRNA is used by ribosomes to synthesize proteins. Replication (A) is the process of copying DNA, not directly related to protein synthesis. Transcription (B) is the step where DNA is transcribed into mRNA. Translation (C) is the process where mRNA is translated into proteins. Therefore, both transcription and translation are essential steps in the flow of genetic information from DNA to protein.

Correct Answer: B

Rationale: The correct answer is B: Bacteria. Dysentery is primarily caused by pathogenic bacteria such as Shigella or Escherichia coli. Bacteria are single-celled microorganisms that can infect the intestines and cause symptoms like bloody diarrhea and abdominal pain. Helminths are parasitic worms that typically cause different types of infections. Protozoa are single-celled organisms that can also cause intestinal infections, but they are not the primary cause of dysentery. Fungi do not typically cause dysentery; they are more commonly associated with skin infections or respiratory issues. In summary, the correct answer is B because dysentery is most commonly caused by bacterial infections in the intestines.

Correct Answer: A

Rationale: The correct answer is A because the atomic number represents the number of protons in the nucleus of an atom, which determines the element's identity. The mass number is the total number of protons and neutrons in the nucleus, indicating the atom's mass. The number of electrons is not directly related to either the atomic or mass number, eliminating choices B and D. Choice C is incorrect because the atomic number specifically refers to the number of protons, not neutrons. Thus, choice A is the only accurate explanation of the difference between the atomic number and the mass number.