Question 1

The simplest form of assisted reproductive technology (ART) is ________, and it can facilitate conception if a man has a low sperm count.
A) ovum transfer
B) gamete intrafallopian transfer
C) artificial insemination
D) in vitro fertilization

Accepted Answer

Artificial insemination is the simplest form of assisted reproductive technology (ART) and is particularly useful when a man has a low sperm count, as it involves directly inserting sperm into a woman's uterus to facilitate fertilization.

Question 2

Which of the following statements is true about adoption?
A) In June 2017, the U.S. Supreme Court ruled that same-sex couples were to be treated as equal under the law, and same-sex adoption is now legal in all 50 states.
B) In 2008, adoptions were unlikely to occur through publicly funded adoption agencies or through intercountry adoption.
C) In August 2011, the U.S. Supreme Court ruled that stepparents could adopt the child of a spouse even if the spouse did not have legal custody of the child.
D) Since the mid-1970s, the percentage of never-married women who adopt out their children has increased significantly.

Accepted Answer

In June 2017, the U.S. Supreme Court ruled in favor of same-sex couples on several issues, including marriage equality, which has had implications for adoption laws, leading to same-sex adoption being legal in all 50 states. This decision reflects the legal recognition of same-sex couples' rights, including the right to adopt.

Question 3

Which of the following is true about the genetic code?
A) Deoxyribonucleic acid (DNA) has a cylindrical structure.
B) Chromosomes are found only in the male and female gamete cells.
C) The complete sequence of genes in the human body constitutes the human genome.
D) A single gene is likely to be located in numerous potential points on a chromosome.

Accepted Answer

The human genome refers to the complete set of nucleic acid sequences for humans, encoded as DNA within the 23 chromosome pairs in cell nuclei and in a small DNA molecule found within individual mitochondria. This encompasses all the genes (including all the nuclear DNA but not the mitochondrial DNA or mtDNA), along with the noncoding sequences.

Question 4

In the context of the genetic code, the fundamental unit of heredity is a chemical called
A) threonine.
B) adenosine monophosphate.
C) arachidonic acid.
D) deoxyribonucleic acid.

Accepted Answer

The fundamental unit of heredity is deoxyribonucleic acid (DNA), which carries the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses.

Question 5

Which of the following is true of meiosis?
A) It results in two cells, each with 46 chromosomes.
B) It reduces the number of chromosomes by half.
C) It refers to the addition of an extra 21st chromosome.
D) It represents the process by which the ovum and sperm combine.

Accepted Answer

Meiosis is a type of cell division that reduces the chromosome number by half, creating four haploid cells, each genetically distinct from the parent cell that gave rise to them. This is essential for sexual reproduction, as it ensures that when gametes (sperm and egg) combine, the resulting offspring has the correct number of chromosomes.

Question 6

Meiosis is a type of cell division in which
A) nonsex cells divide and replicate DNA.
B) permanent alterations are made in genetic material.
C) sex cells end up with 23 chromosomes.
D) recessive disorders are passed on to female children.

Accepted Answer

Meiosis is a specialized form of cell division that reduces the chromosome number by half, resulting in the production of sex cells (sperm and eggs) with 23 chromosomes in humans, ensuring that when they combine during fertilization, the resulting offspring has the normal diploid number of 46 chromosomes.

Question 7

Which of the following is true of the sequence of bases in a gene?
A) It tells the cells how to make the proteins that enable them to carry out specific functions.
B) It is meant to be a recipe for making a particular human.
C) It turns the gene on and off at different points in the development of an individual.
D) It has a double-helix structure and resembles a long, spiraling ladder.

Accepted Answer

The sequence of bases in a gene provides the instructions for synthesizing proteins, which are crucial for cellular functions.

Question 8

In the context of the mechanisms of heredity, normal human females have ________ and normal human males have ________.
A) an XY pairing of chromosomes; an XO pairing of chromosomes
B) an XY pairing of chromosomes; a YX pairing of chromosomes
C) two X chromosomes; an XO pairing of chromosomes
D) two X chromosomes; an XY pairing of chromosomes

Accepted Answer

Normal human females have two X chromosomes (XX), while normal human males have one X and one Y chromosome (XY).

Question 9

________ are chromosomes that are not related to sexual expression.
A) Allosomes
B) Ribosomes
C) Lysosomes
D) Autosomes

Accepted Answer

Autosomes are chromosomes that are not involved in determining the sex of an organism, unlike allosomes (sex chromosomes).

Question 10

During the 1860s, Gregor Mendel laid the foundation for people's understanding of patterns of inheritance. Mendel's most important finding was that
A) genes occur singly and not in pairs.
B) genes do not have fixed positions on chromosomes.
C) dominant traits are expressed only if both copies of a gene are recessive.
D) traits are transmitted independently of each other.

Accepted Answer

Mendel's most important finding was the principle of independent assortment, which states that the alleles for different traits are transmitted to offspring independently of one another. This principle is one of the key concepts of Mendelian genetics.

Question 11

Which of the following exemplifies a homozygous trait in a person?
A) Briana has curly hair similar to that of her parents.
B) Connor has freckles like his father, whereas his mother has clear skin.
C) Jayden, a mixed-race child, takes after his Asian mother who does not have eyelid creases.
D) Nyle's blood type is AB, whereas his mother's and father's blood types are A and B, respectively.

Accepted Answer

A homozygous trait is one where an individual has two identical alleles for a trait. Briana having curly hair similar to her parents suggests she could have inherited the same allele from both, making her homozygous for that trait.

Question 12

A spontaneous dominant mutation known as ________ results in dwarfism.
A) toxoplasmosis
B) achondroplasia
C) bordetella
D) achlorhydria

Accepted Answer

Achondroplasia is a genetic disorder whose hallmark is dwarfism. It is caused by a spontaneous mutation in the gene that codes for fibroblast growth factor receptor 3 (FGFR3), leading to an abnormality in the conversion of cartilage to bone, which is particularly evident in the long bones of the arms and legs.

Question 13

________ is defined as a mechanism that turns genes on or off and determines the functions of body cells.
A) Mitosis
B) Meiosis
C) Phagocytosis
D) Epigenesis

Accepted Answer

Epigenesis refers to the process through which gene expression is regulated, effectively turning genes on or off without altering the DNA sequence itself. This process determines the functions of body cells by influencing which genes are active in particular cells at specific times.

Question 14

In the context of races and ethnicities, which of the following is a true statement about birth disorders?
A) Hispanic infants report the highest rates of hypospadias.
B) Hispanic infants have a higher occurrence of neural tube and ear defects than do non-Hispanic white infants.
C) African American infants are more likely than others to have cleft lip or gastrointestinal abnormalities.
D) Asian American infants are at a higher risk for most birth defects than others.

Accepted Answer

Hispanic infants indeed have a higher occurrence of neural tube defects and ear defects compared to non-Hispanic white infants. This is supported by various health studies and reports that analyze birth defects across different racial and ethnic groups.

Question 15

Which of the following statements is true about the genetic or chromosomal abnormalities that are not apparent at birth and appear later?
A) Huntington's disease results in excessive bleeding in males and typically appears during adolescence.
B) Cystic fibrosis is a condition that is most common in people of northern American descent.
C) Sickle-cell anemia is a metabolic disorder more common among Asian Americans and generally appears in infants between 3 to 4 months of age.
D) Tay-Sachs is a fatal degenerative disease of the central nervous system and is most common in Jews of eastern European ancestry.

Accepted Answer

Tay-Sachs disease is indeed a fatal genetic disorder that affects the central nervous system. It is most commonly found in individuals of Ashkenazi Jewish descent (from Eastern Europe). The other options contain inaccuracies regarding the description of the diseases or the populations they most commonly affect.

Question 16

Beta thalassemia is a birth defect that
A) causes severe anemia, leading to weakness, fatigue, and frequent illness.
B) leads to respiratory failure.
C) leads to the overproduction of mucus, which collects in the lungs and digestive tract.
D) causes poor blood clotting.

Accepted Answer

Beta thalassemia is a genetic blood disorder that reduces the production of hemoglobin, leading to severe anemia, which manifests as weakness, fatigue, and increased susceptibility to infections.

Question 17

Which of the following statements is true about phenylketonuria?
A) It is best treated with the help of enzymes used to improve digestion.
B) It is most likely to be found in families of Mediterranean descent.
C) It is a metabolic disorder that results in intellectual disability.
D) It is an enzyme deficiency that is likely to lead to cirrhosis of the liver in early infancy.

Accepted Answer

Phenylketonuria (PKU) is a metabolic disorder caused by a deficiency in the enzyme phenylalanine hydroxylase, leading to intellectual disability if not treated early with a special diet low in phenylalanine.

Question 18

Recessive defects are expressed only if a child is ________ for that gene.
A) homozygous
B) hemizygous
C) azygous
D) heterozygous

Accepted Answer

Recessive defects are expressed in an individual only if they have two copies of the recessive allele, meaning they are homozygous for that gene.

Question 19

Incomplete dominance is a pattern of inheritance in which
A) multiple genes at different sites on chromosomes affect a complex trait.
B) a child receives identical recessive alleles, resulting in expression of a nondominant trait.
C) a child receives two different alleles, resulting in partial expression of a trait.
D) a child receives different alleles but only the dominant one is expressed.

Accepted Answer

Incomplete dominance occurs when a child inherits two different alleles from their parents, leading to a phenotype that is a blend or partial expression of both alleles, rather than one being completely dominant over the other.

Question 20

Reza, a 2-day-old baby, has muscle weakness and is unable to move his limbs. His doctors perform a surgery to close his spinal canal and to place a shunt inside his brain to drain excess fluid. In the context of birth defects, Reza is likely to have
A) spina bifida.
B) anencephaly.
C) Duchenne muscular dystrophy.
D) Tay-Sachs disease.

Accepted Answer

Reza's symptoms and the description of his surgery suggest he has spina bifida, a birth defect where the spinal canal does not close completely. The placement of a shunt to drain excess fluid indicates the presence of hydrocephalus, which can accompany spina bifida.

Quiz 2: Conception, Environment, and Heredity

The simplest form of assisted reproductive technology (ART) is ________, and it can facilitate conception if a man has a low sperm count.

Which of the following statements is true about adoption?

Which of the following is true about the genetic code?

In the context of the genetic code, the fundamental unit of heredity is a chemical called

Which of the following is true of meiosis?

Meiosis is a type of cell division in which

Which of the following is true of the sequence of bases in a gene?

In the context of the mechanisms of heredity, normal human females have and normal human males have .

________ are chromosomes that are not related to sexual expression.

During the 1860s, Gregor Mendel laid the foundation for people's understanding of patterns of inheritance. Mendel's most important finding was that

Which of the following exemplifies a homozygous trait in a person?

A spontaneous dominant mutation known as ________ results in dwarfism.

________ is defined as a mechanism that turns genes on or off and determines the functions of body cells.

In the context of races and ethnicities, which of the following is a true statement about birth disorders?

Which of the following statements is true about the genetic or chromosomal abnormalities that are not apparent at birth and appear later?

Beta thalassemia is a birth defect that

Which of the following statements is true about phenylketonuria?

Recessive defects are expressed only if a child is ________ for that gene.

Incomplete dominance is a pattern of inheritance in which

Reza, a 2-day-old baby, has muscle weakness and is unable to move his limbs. His doctors perform a surgery to close his spinal canal and to place a shunt inside his brain to drain excess fluid. In the context of birth defects, Reza is likely to have