the outermost layer of the skin providing protection against pathogens and the environment is the

ATI TEAS 7

TEAS 7 science practice

1. Which of the following is the outermost layer of the skin, providing protection against pathogens and the environment?

A. Dermis
B. Epidermis
C. Hypodermis
D. Stratum corneum (part of the epidermis)

Correct answer: B

Rationale: The epidermis is the correct answer as it is the outermost layer of the skin, providing protection against pathogens and the environment. It consists of multiple layers, including the stratum corneum, which is the outermost layer of the epidermis. The dermis is located beneath the epidermis, offering structural support and housing blood vessels, nerves, and glands. The hypodermis is the deepest layer of the skin, made up of fat and connective tissue that secures the skin to underlying structures. Choice A, Dermis, is incorrect as it is located beneath the epidermis. Choice C, Hypodermis, is incorrect as it is the deepest layer of the skin, not the outermost. Choice D, Stratum corneum (part of the epidermis), is not the correct answer as it is a specific layer within the epidermis and not the overall outermost layer of the skin.

2. Which of the following is NOT a part of a plant cell?

A. Cell wall
B. Plasma membrane
C. Vacuole
D. Mitochondria

Correct answer: D

Rationale: A) Cell wall: This is a structure found in plant cells that provides support and protection. B) Plasma membrane: Also known as the cell membrane, it surrounds the cell and regulates the passage of substances in and out of the cell. C) Vacuole: This is a storage organelle found in plant cells that stores water, nutrients, and waste products. D) Mitochondria: Mitochondria are membrane-bound organelles found in both plant and animal cells. They are responsible for producing energy in the form of ATP through cellular respiration. Therefore, the correct answer is D) Mitochondria, as it is a part of a plant cell.

3. Which organelle is responsible for carrying out photosynthesis in plant cells?

A. Golgi apparatus
B. Mitochondria
C. Chloroplasts
D. Lysosomes

Correct answer: C

Rationale: A) Golgi apparatus: The Golgi apparatus is responsible for modifying, sorting, and packaging proteins for secretion or for use within the cell. It is not involved in photosynthesis. B) Mitochondria: Mitochondria are known as the powerhouse of the cell and are responsible for generating energy in the form of ATP through cellular respiration. They are not involved in photosynthesis. C) Chloroplasts: Chloroplasts are the organelles responsible for carrying out photosynthesis in plant cells. They contain chlorophyll, a pigment that captures light energy and converts it into chemical energy in the form of glucose. D) Lysosomes: Lysosomes are membrane-bound organelles that contain digestive enzymes to break down waste materials and cellular debris. They are not involved in photosynthesis. Therefore, the correct answer is C) Chloroplasts, as they are specifically responsible for carrying out photosynthesis in plant

4. What defines the period of a wave?

A. The time it takes for one complete wave cycle to pass a point
B. The distance between two adjacent crests or troughs
C. The number of waves passing a point per unit time
D. The maximum displacement of particles in a medium due to the wave

Correct answer: A

Rationale: The period of a wave is defined as the time it takes for one complete wave cycle to pass a point. It is a crucial parameter in wave analysis and is typically measured in seconds. The period is directly related to the frequency of the wave, as they are reciprocals of each other. Therefore, the correct answer is the time it takes for one complete wave cycle to pass a point (choice A). The period is not related to the number of waves passing a point per unit time (choice C), the distance between two adjacent crests or troughs (choice B), or the maximum displacement of particles in a medium due to the wave (choice D).

5. What is the waxy or oily substance produced by sebaceous glands that helps lubricate the skin and hair?

A. Keratin
B. Melanin
C. Sebum
D. Sweat

Correct answer: C

Rationale: Sebum is the waxy or oily substance produced by sebaceous glands. It helps lubricate the skin and hair, keeping them moisturized and protected. Keratin is a protein that makes up hair, skin, and nails, providing structure and strength. Melanin is a pigment that gives color to the skin, hair, and eyes, providing protection against UV radiation. Sweat is a watery fluid produced by sweat glands to help regulate body temperature by cooling the body through evaporation.