Question 1

Every cell in the human body carries one and only one gene.

Accepted Answer

Each cell in the human body (except for red blood cells and sex cells) contains the entire human genome, which is made up of approximately 20,000 to 25,000 genes.

Question 2

The bulk of a fertile human egg is contributed by the sperm.

Accepted Answer

The bulk of a fertile human egg is contributed by the ovum (egg cell), not the sperm. The ovum is much larger than the sperm and contains the cytoplasm and organelles necessary for early development.

Question 3

Some bicycle seats can cause a reduction in sperm production for some males.

Accepted Answer

Certain bicycle seats, especially those that are narrow and hard, can exert pressure on the perineum (the area between the anus and scrotum), potentially affecting blood flow and nerve function, which in turn can lead to a reduction in sperm production for some males.

Question 4

In deoxyribonucleic acid (DNA), adenine is paired with

Accepted Answer

Adenine pairs with thymine in DNA through two hydrogen bonds, following the base pairing rules.

Question 5

Which pair of chromosomes determines a person's sex?

Accepted Answer

The 23rd pair of chromosomes, also known as the sex chromosomes, determines a person's sex. In humans, females typically have two X chromosomes (XX), while males have one X and one Y chromosome (XY).

Question 6

The mother always contributes a(n)

Accepted Answer

The mother can only contribute an X chromosome to her offspring because females have two X chromosomes (XX), while males have one X and one Y chromosome (XY).

Question 7

Which of the following is caused by a single pair of genes?

Accepted Answer

Cystic fibrosis is caused by a mutation in a single pair of genes (specifically, the CFTR gene), making it a monogenic disorder. Down syndrome is caused by an extra copy of chromosome 21 (trisomy 21), not a single gene mutation. Sex-linked chromosomal abnormalities are related to the X or Y chromosomes but are not caused by a single pair of genes. Crohn's disease is a complex disorder influenced by multiple genes and environmental factors, not a single gene mutation.

Question 8

Which of the following is TRUE regarding amniocentesis and chorionic villus sampling (CVS)?

Accepted Answer

The risks of spontaneous abortion are similar for both procedures, though the specific risk level can vary based on the practitioner's skill and the timing of the procedure. Chorionic villus sampling (CVS) is typically performed earlier in the pregnancy (10-13 weeks) compared to amniocentesis (usually 15-20 weeks). Only CVS involves the examination of villi from the chorion, while amniocentesis involves sampling the amniotic fluid. The skill level required and the risk of complications can vary significantly among practitioners, indicating that not any trained practitioner can carry out these procedures with equal skill.

Question 9

Which of the following twin pair would physically resemble each other the most?

Accepted Answer

Monozygotic twins, also known as identical twins, are formed from a single fertilized egg that splits into two, leading to two individuals with virtually identical genetic material. This results in the highest degree of physical resemblance compared to any other type of twins, regardless of their sex.

Question 10

Studies on monozygotic twins raised in separate homes are useful for

Accepted Answer

Studies on monozygotic twins raised in separate homes are particularly valuable for understanding the genetic basis of behaviors and attitudes. By comparing twins raised apart, researchers can distinguish between traits influenced by genetics and those shaped by the environment, since monozygotic twins share nearly identical genetic makeup.

Question 11

Which statement about sperm is false?

Accepted Answer

Sperm are not attracted to ova by sound waves. Instead, they are guided by chemical signals released by the ovum, a process known as chemotaxis.

Question 12

Adopted children are most likely to become insecure when they are in

Accepted Answer

Middle school is a time of significant social and emotional changes, which can be challenging for adopted children, potentially leading to feelings of insecurity.

Question 13

Match the following:
-Spin a bifida

Accepted Answer

Spina bifida is a neural tube defect, which affects the spine and is apparent at birth.

Question 14

Match the following:
-Phenotype

Accepted Answer

Phenotype refers to the observable characteristics or traits of an organism, which are the manifestations of the genetic material (genotype) interacting with the environment.

Question 15

Match the following:
-Genotype

Accepted Answer

Genotype refers to the genetic material received from parents.

Question 16

Match the following:
-Estrogen

Accepted Answer

Estrogen is known as the female sex hormone, which plays a crucial role in the development and regulation of the female reproductive system and secondary sexual characteristics.

Quiz 2: Heredity and Conception

Every cell in the human body carries one and only one gene.

The bulk of a fertile human egg is contributed by the sperm.

Some bicycle seats can cause a reduction in sperm production for some males.

In deoxyribonucleic acid (DNA) , adenine is paired with

Which pair of chromosomes determines a person's sex?

The mother always contributes a(n)

Which of the following is caused by a single pair of genes?

Which of the following is TRUE regarding amniocentesis and chorionic villus sampling (CVS) ?

Which of the following twin pair would physically resemble each other the most?

Studies on monozygotic twins raised in separate homes are useful for

Which statement about sperm is false?

Adopted children are most likely to become insecure when they are in

Match the following: -Spin a bifida

Match the following: -Phenotype

Match the following: -Genotype

Match the following: -Estrogen