which is true of the process of digestion

ATI TEAS 7

ATI TEAS Science Test

1. Which statement is true regarding the process of digestion?

A. Digestion of starch begins in the mouth.
B. Amylase is produced by the stomach to help break down food in the upper intestine.
C. The di- and tri-saccharides produced in early digestion are absorbed through the intestinal wall.
D. Proteases are responsible for breaking down starches.

Correct answer: A

Rationale: The statement 'Digestion of starch begins in the mouth' is correct. Salivary amylase, an enzyme produced in the salivary glands, initiates the breakdown of starch into simpler sugars like maltose in the mouth before further digestion in the stomach. This initial breakdown of starch is crucial in the digestion of carbohydrates, marking the beginning of the digestive process. Choice B is incorrect because amylase is produced in the salivary glands, not the stomach. Choice C is incorrect because di- and tri-saccharides are further broken down into monosaccharides before absorption. Choice D is incorrect because proteases are enzymes that break down proteins, not starches.

2. What determines the defining characteristic of an element?

A. Neutrons in its nucleus
B. Electrons surrounding the nucleus
C. Protons in its nucleus
D. All of the above

Correct answer: C

Rationale: The defining characteristic of an element is determined by the number of protons in its nucleus, which is referred to as the atomic number. The number of protons uniquely identifies an element. The correct answer is choice C because the number of protons in the nucleus of an atom defines its elemental identity, as different elements have a unique number of protons. Neutrons and electrons do play essential roles in the atom, but they do not determine the defining characteristic of an element. Neutrons contribute to the stability of the nucleus and isotopes of an element, while electrons are involved in chemical bonding and the reactivity of an atom.

3. Which hormone, produced by the pancreas, regulates blood sugar levels by promoting the uptake of glucose into cells?

A. Insulin
B. Glucagon
C. Cortisol
D. Thyroxine

Correct answer: A

Rationale: Insulin is the correct answer. It is produced by the pancreas and plays a crucial role in regulating blood sugar levels by facilitating the absorption of glucose into cells. When blood sugar levels are elevated, insulin is released to help cells utilize glucose for energy or store it for future use. Glucagon, choice B, is produced by the pancreas as well but has the opposite effect of raising blood sugar levels by releasing stored glucose into the bloodstream. Cortisol, choice C, is a hormone produced by the adrenal glands that is involved in the stress response and metabolism, not specifically in regulating blood sugar levels. Thyroxine, choice D, is a hormone produced by the thyroid gland that regulates metabolism but is not directly involved in the uptake of glucose into cells.

4. Which property of matter remains constant regardless of changes in gravity?

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

Correct answer: A

Rationale: Mass is a measure of the amount of matter in an object and remains constant regardless of changes in gravity. This is because mass is an intrinsic property of an object and does not depend on the gravitational field it is in. Weight, on the other hand, is the force of gravity acting on an object's mass and can vary depending on the strength of gravity. Volume is the amount of space an object occupies, which can change depending on the environment. Density is the mass of an object per unit volume, which can also change with variations in gravity. Therefore, the correct answer is Mass as it remains the same regardless of gravitational changes.

5. What type of cells compose the epidermis?

A. Osteoclasts
B. Connective
C. Dendritic
D. Epithelial

Correct answer: D

Rationale: The correct answer is D: Epithelial. The epidermis is composed of epithelial cells, specifically called keratinocytes, which are responsible for producing keratin, a protein that provides the skin with strength and flexibility. Epithelial cells form the protective outer layer of the skin and play a crucial role in skin repair and regeneration. Choice A - Osteoclasts are cells involved in bone remodeling, not found in the epidermis. Choice B - Connective tissue cells are not the primary cells found in the epidermis. They are more commonly found in the dermis, providing structural support and elasticity to the skin. Choice C - Dendritic cells are part of the immune system and are present in the skin to help recognize pathogens and activate the immune response. However, they are not the main cell type that composes the epidermis.