which region of the small intestine is the primary site of absorption

ATI TEAS 7

Practice TEAS Science Test

1. Which region of the small intestine is the primary site of absorption?

A. Duodenum
B. Jejunum
C. Ileum
D. Cecum

Correct answer: B

Rationale: The jejunum is the correct answer. It is the primary site of nutrient absorption in the small intestine. The duodenum mainly facilitates digestion, the ileum is responsible for further absorption, while the cecum is part of the large intestine and not involved in nutrient absorption.

2. What type of reaction is represented by the following equation: 2C₆H₁₄ + 19O₂ → 12CO + 14H₂O?

A. Substitution reaction
B. Acid-base reaction
C. Enzyme reaction
D. Combustion reaction

Correct answer: D

Rationale: The given chemical equation represents a combustion reaction. Combustion reactions involve the burning of a hydrocarbon (C₆H₁₄) in the presence of oxygen (O₂) to produce carbon monoxide (CO) and water (H₂O). Combustion reactions typically release heat and light energy. In this case, the reactants are a hydrocarbon and oxygen, resulting in the formation of carbon monoxide and water. Choices A, B, and C are incorrect because the reaction does not involve substitution, acid-base reactions, or enzyme catalysis. Combustion reactions are characterized by the rapid combination of a substance with oxygen, leading to the production of heat and light energy.

3. Which of the following is NOT a state of matter?

A. Solid
B. Liquid
C. Gas
D. Superfluid

Correct answer: D

Rationale: The correct answer is 'Superfluid.' Superfluid is not considered a traditional state of matter. It is a unique phase of matter that displays zero viscosity and flows without losing kinetic energy. Solids, liquids, and gases are the three classical states of matter distinguished by their physical properties and structures. Therefore, choices A, B, and C are considered states of matter, while choice D, superfluid, is not.

4. Which phenomenon describes the separation of light into its component colors when passing through a prism?

A. Refraction
B. Diffraction
C. Dispersion
D. Reflection

Correct answer: C

Rationale: Dispersion is the phenomenon that describes the separation of light into its component colors when passing through a prism. When white light enters a prism, it is refracted at different angles depending on its wavelength, causing the colors to spread out. Refraction is the bending of light as it passes from one medium to another, not the separation of colors. Diffraction is the bending of light around obstacles, not the separation of colors. Reflection is the bouncing back of light rays from a surface, not the separation of colors. In the context of a prism, dispersion plays a key role in the creation of a spectrum of colors by separating the different wavelengths present in white light.

5. Which of the following describes a difference between cytosol and the mitochondrion?

A. Cytosol is a membrane-bound organelle, but the mitochondrion is not
B. Cytosol is part of the cytoplasm, but the mitochondrion is not
C. The mitochondrion is a membrane-bound organelle, but cytosol is not
D. The mitochondrion is part of the cytoplasm, but cytosol is not

Correct answer: C

Rationale: The mitochondrion is a membrane-bound organelle, while cytosol is the fluid part of the cytoplasm. This differentiation highlights that the mitochondrion has its own membrane structure separating it from the cytoplasm, whereas cytosol is not membrane-bound and represents the liquid portion of the cytoplasm. Choice A is incorrect because cytosol is not a membrane-bound organelle, and the mitochondrion is also not described accurately. Choice B is incorrect as cytosol is indeed part of the cytoplasm. Choice D is incorrect because both the mitochondrion and cytosol are part of the cytoplasm, but the mitochondrion is a membrane-bound organelle unlike cytosol.