TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. What is the "lock-and-key" model?

A. Protein folding
B. Enzyme-substrate interaction
C. Muscle contraction
D. Blood clotting

Correct answer: B

Rationale: Rationale: The "lock-and-key" model is a concept used to describe the specificity of the interaction between enzymes and their substrates. In this model, the enzyme's active site is like a lock that can only be opened by the specific substrate molecule, which acts as the key. This specific binding ensures that enzymes catalyze specific reactions and do not interact with other molecules indiscriminately. Protein folding (option A) refers to the process by which a protein adopts its functional three-dimensional structure, but it is not specifically related to the lock-and-key model. Muscle contraction (option C) and blood clotting (option D) are biological processes that involve complex mechanisms but are not directly related to the lock-and-key model of enzyme-substrate interaction.

2. The speed of light in a vacuum is measured in units of:

A. Meters per second
B. Hertz
C. Candela
D. Newton

Correct answer: A

Rationale: The correct answer is A: 'Meters per second.' The speed of light in a vacuum is a fundamental constant of nature and is approximately 299,792,458 meters per second. This speed is constant and does not vary based on the frequency or wavelength of light. Hertz (B) is a unit of frequency, Candela (C) is a unit of luminous intensity, and Newton (D) is a unit of force. Understanding the units used to measure the speed of light is important in physics and related fields to accurately describe the propagation of light in different mediums.

3. What is the final stage of both mitosis and meiosis?

A. Interphase
B. Telophase
C. Cytokinesis
D. G1 phase

Correct answer: B

Rationale: Rationale: - Interphase (option A) is not the final stage of mitosis or meiosis; it is the phase before cell division where the cell prepares for division by growing and replicating its DNA. - Telophase (option B) is the final stage of both mitosis and meiosis. During telophase, the separated chromosomes reach opposite poles of the cell, the nuclear membrane reforms around each set of chromosomes, and the chromosomes begin to decondense. - Cytokinesis (option C) is the process of dividing the cytoplasm to form two separate daughter cells. While it occurs after telophase, it is not considered the final stage of mitosis or meiosis. - G1 phase (option D) is the first gap phase in the cell cycle, occurring before DNA replication. It is not the final stage of mitosis or meiosis.

4. What is the main function of vacuoles in plant cells?

A. To provide structural support for the cell
B. To transport substances in and out of the cell
C. To synthesize proteins and lipids
D. To store water, enzymes, and waste products

Correct answer: D

Rationale: Rationale: Vacuoles in plant cells primarily function as storage organelles. They store water, enzymes, pigments, and waste products. Vacuoles help maintain turgor pressure within the cell, which provides structural support for the plant cell. While vacuoles can also be involved in transporting substances within the cell, their main function is storage. Synthesizing proteins and lipids is primarily carried out by other organelles such as the endoplasmic reticulum and Golgi apparatus.

5. Which nitrogenous bases pair with each other in DNA?

A. A-G and T-C
B. A-T and C-G
C. -A and T-T
D. C-C and G-G

Correct answer: B

Rationale: Rationale: In DNA, nitrogenous bases pair with each other in a specific manner known as complementary base pairing. Adenine (A) always pairs with Thymine (T), and Cytosine (C) always pairs with Guanine (G). This pairing is essential for maintaining the structure and function of DNA. Therefore, option B is the correct answer as it correctly identifies the nitrogenous bases that pair with each other in DNA.