TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. The Minimum Inhibitory Concentration (MIC) of an antibiotic refers to:

A. The lowest concentration that kills bacteria
B. The dose required for 50% bacterial inhibition
C. The time it takes for an antibiotic to work
D. The spectrum of bacteria the antibiotic targets

Correct answer: B

Rationale: Rationale: A) The lowest concentration that kills bacteria is known as the Minimum Bactericidal Concentration (MBC), not the Minimum Inhibitory Concentration (MIC). MIC is the lowest concentration of an antibiotic that inhibits visible growth of bacteria. B) The MIC of an antibiotic is the concentration at which bacterial growth is inhibited by 50%. This concentration is used to determine the effectiveness of an antibiotic against a specific bacterium. C) The time it takes for an antibiotic to work is not described by the MIC. MIC is a measure of concentration, not time. D) The spectrum of bacteria the antibiotic targets is not defined by the MIC. The MIC value is specific to a particular antibiotic and bacterium, regardless of the spectrum of activity of the antibiotic.

2. Which component of the nervous system is responsible for controlling voluntary movements, such as the contraction of skeletal muscles?

A. Autonomic nervous system
B. Peripheral nervous system
C. Somatic nervous system
D. Sympathetic nervous system

Correct answer: c

Rationale: The correct answer is C, the somatic nervous system. The somatic nervous system is responsible for controlling voluntary movements, such as the contraction of skeletal muscles. This system consists of motor neurons that send signals from the central nervous system to the skeletal muscles, allowing us to consciously control our movements. The autonomic nervous system (A) controls involuntary actions like heart rate and digestion, the peripheral nervous system (B) includes all nerves outside of the brain and spinal cord, and the sympathetic nervous system (D) is a division of the autonomic nervous system responsible for the fight-or-flight response. Therefore, the somatic nervous system is specifically involved in voluntary movements.

3. The pH scale is used to indicate the concentration of:

A. Oxygen
B. Hydrogen ions
C. Salts
D. Sugar molecules

Correct answer: A

Rationale: The pH scale measures the concentration of hydrogen ions in a solution, indicating acidity or basicity.

4. The kidneys are bean-shaped organs that perform several vital functions. Which of the following is NOT a primary function of the kidneys?

A. Filtering waste products from the blood
B. Regulating blood pressure
C. Producing red blood cells
D. Maintaining water balance in the body

Correct answer: C

Rationale: The correct answer is C. While the kidneys perform multiple vital functions, such as filtering waste products from the blood, regulating blood pressure, and maintaining water balance in the body, they do not produce red blood cells. Red blood cell production occurs in the bone marrow, specifically in the spongy tissue called the red bone marrow. Therefore, the kidneys' primary functions do not include producing red blood cells.

5. What is the function of introns in eukaryotic genes?

A. They code for protein sequences.
B. They are involved in gene regulation.
C. They are removed during mRNA processing.
D. They are non-functional remnants of ancient DNA.

Correct answer: C

Rationale: Rationale: A) Introns do not code for protein sequences. Exons are the segments of DNA that code for proteins. B) While introns can indirectly influence gene regulation, their primary function is not directly involved in gene regulation. C) Introns are non-coding regions of DNA that are transcribed into pre-mRNA but are removed during mRNA processing through a process called splicing. This allows only the exons to be included in the mature mRNA that will be translated into proteins. D) While introns were once thought to be non-functional remnants of ancient DNA, research has shown that they can have regulatory functions and play a role in gene expression.