TEAS 7 Chemistry: Essential Practice for Success

ATI TEAS 7

Chemistry

1. What is the formula for calculating molarity?

A. M = n/V
B. M = n/L
C. M = mol/L
D. M = mol/dmÂ³

Correct answer: a

Rationale: All of these choices are equivalent to the original formula. The symbol "n" represents the number of moles of solute, and the symbol "V" represents the volume of the solution in liters. The symbol "L" is an abbreviation for "liters," and "dmÂ³" is an alternative way to represent liters.

2. What is the name of the structure that packages DNA in eukaryotic cells?

A. Nucleosome
B. Chromatin
C. Histone
D. Centromere

Correct answer: A

Rationale: Rationale: - A nucleosome is the basic structural unit of DNA packaging in eukaryotic cells. It consists of DNA wrapped around a core of histone proteins. - Chromatin refers to the complex of DNA and proteins found in the nucleus of a eukaryotic cell, including nucleosomes. - Histones are the proteins around which DNA is wrapped to form nucleosomes. - Centromere is a region of a chromosome where the two sister chromatids are joined and to which spindle fibers attach during cell division.

3. Identify the comprehensive protection for the brain.

A. Skull
B. Meninges (Membranes)
C. Cerebrospinal fluid
D. All of the above

Correct answer: D

Rationale: Rationale: A) The skull provides a hard, protective covering for the brain, shielding it from external trauma and injury. B) The meninges are three layers of membranes (dura mater, arachnoid mater, and pia mater) that surround the brain and spinal cord, providing additional protection and cushioning. C) Cerebrospinal fluid is a clear, colorless fluid that surrounds the brain and spinal cord, acting as a shock absorber and providing nutrients to the central nervous system. Together, the skull, meninges, and cerebrospinal fluid work in conjunction to provide comprehensive protection for the brain, making option D the correct answer.

4. Which part of the spinal cord is responsible for transmitting sensory information from the body to the brain?

A. Dorsal root
B. Ventral root
C. Gray matter
D. White matter

Correct answer: a

Rationale: The correct answer is A: Dorsal root. The dorsal root of the spinal cord is responsible for transmitting sensory information from the body to the brain. This root contains sensory nerve fibers that carry information such as touch, temperature, and pain signals from the peripheral nervous system to the central nervous system. Ventral roots, on the other hand, are responsible for transmitting motor information from the brain to the muscles. Gray matter is primarily composed of nerve cell bodies and is involved in processing information, while white matter consists of myelinated nerve fibers that facilitate communication between different parts of the nervous system. Therefore, in this context, the dorsal root is the specific structure that handles sensory information transmission.

5. During exercise, heart rate increases to deliver more oxygen to the body's tissues. What other cardiovascular response also increases?

A. Blood pressure decreases
B. Blood vessel diameter narrows
C. Blood flow to muscles increases
D. Blood viscosity thickens

Correct answer: A

Rationale: The correct answer is A: 'Blood pressure decreases.' When the heart rate increases during exercise to deliver more oxygen to the body's tissues, the blood pressure also tends to decrease. This is due to the enhanced efficiency of the heart in pumping blood, resulting in a lower pressure exerted on the blood vessel walls. In contrast, options B and D are incorrect as blood vessel diameter typically widens (dilates) during exercise to facilitate increased blood flow, and blood viscosity does not usually thicken during exercise. Option C is a distractor as blood flow to muscles indeed increases during exercise to meet the higher demand for oxygen and nutrients.