Question 1

Individuals with Klinefelter syndrome have:

Accepted Answer

Klinefelter syndrome is characterized by the presence of an extra X chromosome in males, leading to an XXY chromosomal pattern.

Question 2

Individuals who have an extra chromosome on the 21^st chromosomal pair usually develop signs of:

Accepted Answer

Down's syndrome is characterized by an individual having an extra chromosome on the 21st chromosomal pair.

Question 3

Females with Turner syndrome have:

Accepted Answer

Turner syndrome is characterized by a single X chromosome (45,X) instead of the usual two sex chromosomes in females (46,XX).

Question 4

Matt is a 36-year-old male. In the past year, he has noticed that his limbs sometimes move on their own, and he has also started having trouble remembering things and doing simple calculations. Matt's father and grandfather were also known to have similar problems during their adulthood. Matt is most likely suffering from:

Accepted Answer

Huntington's disease (HD) is a genetic disorder that affects the brain and causes progressive degeneration of nerve cells, leading to symptoms such as involuntary movements (chorea), cognitive decline, and psychiatric issues. The fact that Matt's father and grandfather had similar problems suggests a hereditary pattern, which aligns with HD's autosomal dominant inheritance. The other options listed do not typically present with these symptoms or inheritance patterns.

Question 5

Which of the following genetic abnormalities is considered a multifactorial problem?

Accepted Answer

Diabetes mellitus is considered a multifactorial problem because it involves a combination of genetic predispositions and environmental factors such as diet, exercise, and lifestyle.

Question 6

Which of the following statements is true of sickle cell?

Accepted Answer

Sickle cell disease is characterized by the production of abnormal hemoglobin, which causes red blood cells to assume a sickle shape. These misshapen cells can block blood flow in small vessels, leading to pain, organ damage, and a decreased oxygen supply to tissues.

Question 7

Twenty-year-old Jack is extremely tall and has very thick facial hair. Most of his male secondary sex characteristics are also more pronounced than men of his age. In this scenario, Jack is most likely:

Accepted Answer

Jack's symptoms suggest he is an XYY male, a condition associated with an extra Y chromosome, which can lead to taller stature and more pronounced male secondary sex characteristics.

Question 8

Who among the following is most likely to have gynecomastia?

Accepted Answer

Gynecomastia is the enlargement of breast tissue in males, and it is most commonly associated with Klinefelter syndrome, which is characterized by an extra X chromosome (XXY). Peter, who has Klinefelter syndrome, is therefore the most likely to have gynecomastia.

Question 9

Tim, a 27-year-old man, has unusually narrow shoulders, low muscle mass, and has no facial and body hair. His doctor recently prescribed testosterone replacement therapy to him. Tim is most likely suffering from:

Accepted Answer

Tim's symptoms, including narrow shoulders, low muscle mass, and lack of facial and body hair, along with the prescription of testosterone replacement therapy, suggest he has Klinefelter syndrome. This condition is characterized by an extra X chromosome in males (XXY), leading to hypogonadism and the need for testosterone treatment.

Question 10

Daisy was always unusually short for her age. She was unable to conceive a child after marriage, and upon visiting a doctor, she was prescribed estrogen replacement therapy. Daisy is most likely suffering from:

Accepted Answer

Turner syndrome is characterized by a missing or partially missing X chromosome, which can lead to short stature and infertility, both of which Daisy is experiencing. Estrogen replacement therapy is often prescribed to help develop secondary sexual characteristics and address hormonal deficiencies.

Question 11

Which of the following statements describes a deficit often encountered by supermales?

Accepted Answer

Supermales, who have an XYY chromosome configuration, often experience mildly delayed language development among other symptoms, but do not typically suffer from the other conditions listed.

Question 12

When the effects of both alleles are shown, there is said to be ______.

Accepted Answer

Codominance occurs when both alleles in a gene pair are fully expressed, allowing both traits to be shown simultaneously in the phenotype.

Question 13

Individuals with Down's syndrome ______.

Accepted Answer

Individuals with Down's syndrome typically show deficits in cognitive development due to the presence of an extra chromosome 21, which affects brain development and function.

Question 14

Pairs of chromosomes that look alike and possess genetic information concerning the same set of traits are termed _____.

Accepted Answer

The answer of Pairs of chromosomes that look alike and...

Question 15

Jill bears the genetic code for Von Willebrand disease, but she has never developed the illness herself. Jill would be considered ______.

Accepted Answer

Von Willebrand disease is a genetic disorder that affects blood clotting. If Jill carries the genetic code for the disease but does not exhibit symptoms, she is a carrier of the gene. This means she has inherited the gene but it does not manifest as the disease in her, which is typical for recessive genes when only one copy is present.

Question 16

A recessive gene is the main cause of:

Accepted Answer

Huntington's disease is caused by a dominant gene, Turner syndrome and Down's syndrome are chromosomal disorders not caused by a single gene, whereas Sickle cell disease is caused by a recessive gene, meaning an individual must inherit two copies of the abnormal gene (one from each parent) to develop the disease.

Question 17

When both alleles for a trait are different, the person is said to be _____.

Accepted Answer

When an individual has two different alleles for a specific trait, they are considered to be heterozygous for that trait.

Question 18

Rico is a man who has enlarged breasts and suffers from mild intellectually disability. He has a problem learning languages, and his body produces less of the male sex hormone testosterone than normal males. Rico is most likely suffering from:

Accepted Answer

Klinefelter syndrome is characterized by the presence of an extra X chromosome in males, leading to symptoms such as enlarged breasts, reduced testosterone levels, and learning difficulties, which matches Rico's condition.

Question 19

If an individual gets a dominant gene for eye color from one parent, and a recessive gene from another, the ______.

Accepted Answer

Dominant genes mask the effect of recessive genes, so if an individual inherits a dominant gene for a trait from one parent and a recessive gene for the same trait from the other parent, the dominant trait will be expressed.

Question 20

Which of the following statements is true of Down's syndrome?

Accepted Answer

Down's syndrome is primarily caused by an extra copy of chromosome 21 (trisomy 21), not by defects in sex chromosomes or sexually transmitted infections. The risk of having a child with Down's syndrome does indeed increase with the age of the parents, especially the mother.

Quiz 2: Heredity and Prenatal Development