what does the large intestine absorb

ATI TEAS 7

ATI TEAS Science Practice Test

1. What do large intestines absorb?

A. Water, sodium, and potassium ions
B. Proteins and carbohydrates
C. Water, vitamin K, and bile salts
D. Vitamins A, D, E, K

Correct answer: C

Rationale: The correct answer is C. The large intestine absorbs water, vitamin K, bile salts, sodium, and chloride ions. It helps in maintaining the body's water and electrolyte balance, and also plays a role in absorbing certain vitamins and nutrients such as vitamin K. Choices A, B, and D are incorrect because proteins, carbohydrates, vitamins A, D, E, and K are primarily absorbed in the small intestine, not the large intestine.

2. Which of the following is true regarding adipocytes?

A. They are involved in the secretion of glucose.
B. They are responsible for storing the fat found in adipose tissue.
C. They are critical in the digestive breakdown of fat.
D. They are the foundational element of muscles.

Correct answer: B

Rationale: The correct answer is B. Adipocytes are responsible for storing the fat found in adipose tissue. These specialized cells store energy in the form of fat and play a key role in energy balance and metabolism. Adipocytes do not secrete glucose; that function is typically attributed to other cells like pancreatic beta cells. Adipocytes are not involved in the digestive breakdown of fat, as this process primarily occurs in the gastrointestinal system with the help of enzymes. Adipocytes are distinct from the foundational elements of muscles, which are primarily made up of muscle fibers and associated connective tissues.

3. What are the fluid-filled sacs that cushion the brain within the skull called?

A. Meninges
B. Cerebrospinal fluid
C. Dura mater
D. Arachnoid mater

Correct answer: B

Rationale: The correct answer is B, cerebrospinal fluid. Cerebrospinal fluid acts as a shock absorber, protecting the brain from impact and providing nutrients to brain cells. Meninges are the three protective layers of tissue that surround the brain and spinal cord. Dura mater and arachnoid mater are specific layers of the meninges, not the fluid-filled sacs that cushion the brain.

4. The Hardy-Weinberg equilibrium describes a population that is:

A. Undergoing rapid evolution due to strong directional selection.
B. Not evolving and at genetic equilibrium with stable allele frequencies.
C. Experiencing a founder effect leading to a reduction in genetic diversity.
D. Dominated by a single homozygous genotype that eliminates all variation.

Correct answer: B

Rationale: The Hardy-Weinberg equilibrium describes a theoretical population in which allele frequencies remain constant from generation to generation, indicating that the population is not evolving. This equilibrium occurs under specific conditions: no mutation, no gene flow, random mating, a large population size, and no natural selection. In this scenario, all genotypes are in proportion to the allele frequencies, and genetic diversity is maintained. Options A, C, and D do not accurately describe a population in Hardy-Weinberg equilibrium. Option A suggests rapid evolution due to strong directional selection, which would disrupt the equilibrium. Option C mentions a founder effect, which can reduce genetic diversity but is not a characteristic of a population in Hardy-Weinberg equilibrium. Option D describes a population dominated by a single homozygous genotype, which also does not align with the genetic diversity seen in a population at Hardy-Weinberg equilibrium.

5. Which property remains constant despite possible changes to the element?

A. Atomic number
B. Number of electrons
C. Atomic mass
D. Isotopic form

Correct answer: A

Rationale: The correct answer is 'Atomic number' (A). The atomic number of an element remains constant as it defines the number of protons in the nucleus, which does not change despite various chemical reactions or physical processes affecting the element. The number of protons in the nucleus determines the identity of the element, and this fundamental property remains unchanged even if the element undergoes chemical reactions, forms ions, or changes its physical state. Choices B, C, and D are incorrect because the number of electrons (B) can change in chemical reactions, atomic mass (C) can vary with isotopes, and isotopic form (D) refers to variations in the number of neutrons in the nucleus, which can result in different isotopes of an element.