TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. Decomposers in an ecosystem play a vital role by:

A. Photosynthesizing and producing organic matter
B. Breaking down dead organisms and returning nutrients to the environment
C. Preying on herbivores and controlling their populations
D. Fixing nitrogen from the atmosphere and making it available to plants

Correct answer: B

Rationale: Rationale: Decomposers are organisms that break down dead organic matter, such as dead plants and animals, into simpler substances. By doing so, they help to recycle nutrients back into the environment, making them available for other organisms to use. This process is essential for the functioning of ecosystems, as it ensures that nutrients are not lost but instead are continuously cycled through the ecosystem. Photosynthesis (option A) is the process by which plants and some other organisms convert light energy into chemical energy in the form of glucose, and it is not a role of decomposers. Preying on herbivores (option C) is a role typically carried out by predators, not decomposers. Fixing nitrogen from the atmosphere (option D) is a process carried out by nitrogen-fixing bacteria, not decomposers.

2. The thymus gland, crucial for immune system development, is located in the:

A. Chest
B. Abdomen
C. Pelvis
D. Head and neck

Correct answer: A

Rationale: The thymus gland, an essential organ for immune system development, is located in the chest region, specifically in the upper part of the chest behind the breastbone. It plays a vital role in the maturation of T-cells, a type of white blood cell crucial for immune responses. The thymus gland is part of the lymphatic system and is most active during childhood and adolescence, gradually decreasing in size and function with age. Its location in the chest allows it to interact closely with other immune system components in the body, making it a key player in maintaining overall immune health.

3. The process of splitting a heavy nucleus into smaller nuclei, releasing a vast amount of energy, is called:

A. Nuclear fusion
B. Nuclear fission
C. Radioactive decay
D. Chain reaction

Correct answer: B

Rationale: Rationale: Nuclear fission is the process of splitting a heavy nucleus into smaller nuclei, releasing a vast amount of energy. This process is commonly used in nuclear power plants and nuclear weapons. A) Nuclear fusion is the process of combining two light nuclei to form a heavier nucleus, releasing energy in the process. This process powers the sun and other stars. C) Radioactive decay is the process by which an unstable atomic nucleus loses energy by emitting radiation. D) Chain reaction is a self-sustaining reaction in which the products of one reaction event stimulate further reaction events. This can occur in both nuclear fission and nuclear fusion reactions.

4. Which of the following is the main organ responsible for storing energy?

A. Liver
B. Heart
C. Kidneys
D. Adipose tissue

Correct answer: D

Rationale: Rationale: - Adipose tissue, commonly known as body fat, is the main organ responsible for storing energy in the form of triglycerides. - The liver plays a role in energy metabolism by regulating glucose levels and storing glycogen, but its primary function is not energy storage. - The heart is a muscular organ responsible for pumping blood throughout the body and does not play a significant role in energy storage. - The kidneys are vital organs responsible for filtering blood and regulating fluid balance, but they are not primarily involved in energy storage.

5. What property of a substance remains constant regardless of the amount of the substance present?

A. Mass
B. Weight
C. Density
D. Volume

Correct answer: c

Rationale: Density remains constant for a specific substance regardless of the quantity present. It's the mass per unit volume and remains the same for a substance.