Question 1

Determining the location of specific genes on specific chromosomes is referred to as

Accepted Answer

Genetic mapping is the process of determining the location of specific genes on specific chromosomes. Phenomapping, chromosomal atlasing, and genome projection do not refer specifically to the process of locating genes on chromosomes.

Question 2

Shane and Blane are identical (monozygotic) twins; however, people seldom get the two brothers mixed up because Blane is almost two inches shorter than Shane. The difference in height means that

Accepted Answer

The fact that Shane and Blane are identical suggests that they have the same genotype. However, the difference in height means that they display different phenotypes. This indicates that even though they have the same genotype, there are other factors affecting their height that result in different phenotypes. These factors could include environmental factors such as nutrition or hormone levels during development. Therefore, option C is correct.

Question 3

When the two genes in a specific pair are the same, the individual is

Accepted Answer

When the two genes in a specific pair are the same, the individual is homozygous for that trait. This means that they have inherited two copies (one from each parent) of the same version of the gene for that trait.

Question 4

The observable characteristics of an individual are referred to as that person's

Accepted Answer

Phenotype refers to the observable characteristics of an individual, while genotype refers to the genetic makeup of an individual. Zygotype is not a commonly used term in genetics, and heritability refers to the extent to which differences in a trait among individuals can be attributed to genetic factors.

Question 5

A ____ contains thousands of ____.

Accepted Answer

A chromosome contains many genes arranged in a linear sequence along its length. DNA molecules are tightly packed together to form chromosomes. Therefore, option C is the correct answer. Option A is incorrect because although DNA contains genes, it is not present in thousands. Option B is incorrect because although DNA forms chromosomes, the thousands of units referred to in the question are genes. Option D is incorrect because a single gene cannot contain thousands of chromosomes.

Question 6

Donald and Ronald are identical twins who have been raised apart, in separate adoptive homes. However, both brothers have developed the same psychological disorder. This information could be used as evidence to suggest that

Accepted Answer

The fact that both identical twins who were raised in separate adoptive homes have the same psychological disorder suggests that there is a strong genetic component to this disorder. If the disorder was solely influenced by environmental factors, we would expect the twins to have different outcomes due to their different upbringing. Therefore, option C is the best choice.

Question 7

While ____ refers to a person's genetic makeup, ____ refers to a person's observable characteristics.

Accepted Answer

Genotype refers to the genetic makeup of an organism, which includes all of its genes, while phenotype refers to the observable characteristics or traits of an organism, such as its physical appearance, behavior, and development, which are influenced by both its genotype and environmental factors.

Question 8

When a dominant gene is paired with a recessive gene, the gene pair is said to be

Accepted Answer

When a dominant gene is paired with a recessive gene, the gene pair is referred to as heterozygous. Heterozygous means that there is a different gene on each of the paired chromosomes. Homozygous means that both genes on the paired chromosomes are the same. Phenotypic refers to the physical expression of the genes, and polygenic refers to when multiple genes contribute to a single trait.

Question 9

Which of the following are generally considered the key functional units in hereditary transmission?

Accepted Answer

Genes are the key functional units in hereditary transmission, as they carry the genetic information that is passed down from parents to offspring. Chromosomes are made up of genes, but they are not the primary functional unit. Dichromats are individuals with color vision deficiency, and limens are threshold stimuli in sensory perception, neither of which are directly related to hereditary transmission.

Question 10

The result of the fertilisation of an egg by a sperm is a

Accepted Answer

The result of fertilization of an egg by a sperm is a zygote, which is the first stage of development for a new individual. A chromosome is a thread-like structure that carries genetic information, and a gene is a segment of DNA that determines a particular trait. A foetus is a developing offspring after the zygote has undergone several stages of development.

Question 11

Charise has blue eyes and blonde hair. Genetically, this description refers to Charise's

Accepted Answer

The description of Charise's physical traits (blue eyes and blonde hair) refers to her phenotype, which is the observable physical characteristics resulting from the expression of her genes. Somatotype refers to the classification of body types based on physical characteristics such as height, weight, and body shape. Genotype refers to an individual's complete set of heritable genes, while prototype refers to a standard or model from which other things are developed or copied.

Question 12

Skin colour is determined by three to five gene pairs. This makes skin colour

Accepted Answer

Skin colour is determined by multiple gene pairs, not just one, making it a polygenic trait.

Question 13

Which of the following is determined at conception and is fixed forever?

Accepted Answer

Genotype refers to the genetic makeup of an individual, which is determined at conception and remains fixed for life. Phenotype refers to the observable physical characteristics of an individual, which can be influenced by both genetic and environmental factors. Somatotype refers to the body type or physique of an individual, which can also be influenced by both genetic and environmental factors. Prototype refers to a preliminary or tentative model of something, and is not related to biological traits.

Question 14

Dr Solomons is a molecular geneticist interested in researching the influence of heredity on behaviour. The technique that Dr Solomons would be MOST likely to use is

Accepted Answer

Genetic mapping is specifically focused on identifying genetic influences on behavior, which is the main interest of Dr Solomons. Chromosomal atlasing and genome projection are more general techniques for visualizing and analyzing genetic information, and phenomapping is focused on identifying patterns in disease symptoms rather than genetic influences on behavior. Therefore, genetic mapping is the most relevant technique for Dr Solomons' research interests.

Question 15

Family studies, twin studies and adoption studies are primarily designed to

Accepted Answer

Family studies, twin studies, and adoption studies are all methods used to help researchers understand the extent to which genetics and experience influence different behavioral traits. These methods involve comparing the similarities and differences between individuals who are genetically related (such as family members or twins) or who have been raised in different environments (such as adoptees). By using these methods, researchers can gain insight into how genetics and experience interact to shape behavior.

Question 16

Londra and Sondra are identical twins who have been raised together in the same home. Londra has developed a psychological disorder, but Sondra does not appear to have the same disorder. This information could be used as evidence to suggest that

Accepted Answer

Since Londra and Sondra are identical twins who have been raised together in the same home, it can be assumed that their genetic makeup is almost identical. Therefore, any differences between the two twins can likely be attributed to environmental factors, rather than genetic factors. Since Londra has developed a psychological disorder, but Sondra has not, this suggests that environmental factors (such as different life experiences, for example) may have had more influence on the development of the disorder than any genetic factors.

Question 17

It is most accurate to state that family, twin and adoption studies are designed to determine the effect of ____ on human behaviour.

Accepted Answer

Family, twin and adoption studies are designed to determine the effect of both experience and genetics on human behavior. These studies compare the similarities and differences in behavior among individuals who share varying degrees of genetic and environmental similarity. The comparison helps to determine the extent to which genes and environment influence behavior.

Question 18

Slindile and her four sisters are all artistically inclined and enjoy working on creative projects. When she meets her three cousins for the first time, Slindile is somewhat surprised to find that none of them have any interest at all in art. The differences between Slindile's sisters and her cousins could be used as evidence to suggest that

Accepted Answer

The answer of Slindile and her four sisters are all...

Question 19

The specific pattern of genes inherited at conception defines an individual's

Accepted Answer

The specific pattern of genes inherited at conception is the genotype of an individual. This genotype determines the genetic makeup of individuals and influences their physical and behavioral traits.

Question 20

Dudu was adopted at birth by Mr and Mrs Nduna. Although neither of his biological parents had much musical ability, Dudu has become an excellent pianist, just like Mr Nduna. This information could be used as evidence to suggest that

Accepted Answer

Dudu's musical talent, despite his biological parents' lack of musical ability, suggests that the environment (growing up with a pianist adoptive father) played a significant role in developing his musical skills, indicating that environmental factors can have a strong influence on such talents.

Quiz 3: Biology of Behaviour