what potential consequences can chromosomal nondisjunction have on offspring

ATI TEAS 7

ati teas 7 science

1. What potential consequences can chromosomal nondisjunction have on offspring?

A. Down syndrome, caused by an extra copy of chromosome 21.
B. Turner syndrome, characterized by the absence of one X chromosome in females.
C. Klinefelter syndrome, featuring one or more extra X chromosomes in males.
D. All of the above.

Correct answer: D

Rationale: - Chromosomal nondisjunction is the failure of homologous chromosomes or sister chromatids to separate properly during cell division, leading to an abnormal number of chromosomes in the resulting cells. - Down syndrome is caused by an extra copy of chromosome 21, resulting from nondisjunction during meiosis. Individuals with Down syndrome have three copies of chromosome 21 instead of the usual two. - Turner syndrome is characterized by the absence of one X chromosome in females, leading to a variety of physical and developmental features. - Klinefelter syndrome features one or more extra X chromosomes in males, typically resulting in infertility and other physical characteristics. Therefore, chromosomal nondisjunction can lead to various genetic disorders such as Down syndrome, Turner syndrome, and Klinefelter syndrome, making option D the correct answer.

2. What is the primary function of the cell membrane?

A. To provide structural support for the cell
B. To transport substances in and out of the cell
C. To synthesize proteins and lipids
D. To store genetic material

Correct answer: B

Rationale: The primary function of the cell membrane, also known as the plasma membrane, is to regulate the movement of substances in and out of the cell. It acts as a selectively permeable barrier, allowing specific molecules to pass through while blocking others. This role is crucial for maintaining the internal environment of the cell by enabling essential nutrients to enter and waste products to exit. While the cell membrane provides some structural support for the cell, its main function is substance transport. Protein and lipid synthesis predominantly occur in organelles like the endoplasmic reticulum and Golgi apparatus, and storing genetic material is the nucleus's responsibility. Therefore, choices C (To synthesize proteins and lipids) and D (To store genetic material) are incorrect as these functions are carried out by other cell organelles, not the cell membrane.

3. What functional group is present in esters?

A. Hydroxyl
B. Carbonyl
C. Ester
D. Amine

Correct answer: C

Rationale: The functional group present in esters is -COO-, which represents a carbonyl group bonded to an oxygen atom. This group is responsible for the characteristic fruity aroma of esters. Choice A, 'Hydroxyl,' refers to -OH, which is a characteristic group of alcohols, not esters. Choice B, 'Carbonyl,' is a broad term that includes various compounds with a C=O group, but specifically in esters, it is a carbonyl group bonded to an oxygen atom. Choice D, 'Amine,' refers to compounds containing a nitrogen atom bonded to hydrogen atoms or alkyl groups, which is not present in esters. Therefore, the correct answer is 'C: Ester.'

4. Where is the gastrocnemius vein in relation to the femoral vein?

A. Lateral
B. Distal
C. Superior
D. Ventral

Correct answer: A

Rationale: The gastrocnemius vein is located lateral to the femoral vein. In anatomical terms, lateral refers to the direction towards the side of the body or away from the midline. In this case, the gastrocnemius vein is positioned to the side of the femoral vein. The term 'distal' refers to being further away from the point of reference, 'superior' indicates a higher position, and 'ventral' refers to the front or anterior aspect of the body. Therefore, the correct answer is A. Lateral.

5. What type of muscle is found in the walls of the heart?

A. Smooth muscle
B. Cardiac muscle
C. Skeletal muscle
D. Voluntary muscle

Correct answer: B

Rationale: The correct answer is B: Cardiac muscle. Cardiac muscle is the specialized muscle found in the walls of the heart. It contracts involuntarily to pump blood throughout the body, ensuring circulation. Smooth muscle is typically found in organs like the intestines and blood vessels, aiding in their functions. Skeletal muscle is attached to bones and plays a vital role in movement and posture. Voluntary muscle is a general term for skeletal muscles that are under conscious control, unlike cardiac muscle which contracts involuntarily to maintain the heart's continuous pumping action.