Question 1

Which statement best supports the hypothesis that intelligence is partly influenced by environmental factors

Accepted Answer

If intelligence were solely determined by genetics, then identical twins would have identical intelligence scores. The fact that they do not supports the idea that environmental factors also play a role in intelligence.

Question 2

Which hormone is associated with bonding and trust

Accepted Answer

Oxytocin is known as the "love hormone" and is associated with bonding and trust between individuals. It is involved in social behaviors, such as maternal-infant bonding, sexual intimacy, and social bonding between individuals.

Question 3

What is a person's genotype

Accepted Answer

A person's genotype refers to their genetic makeup, specifically the unique combination of alleles inherited from their parents that determines their traits and characteristics. It is different from their phenotype, which refers to their observable traits and characteristics.

Question 4

What do we call the interdisciplinary field that studies the influence of inherited traits on complex behaviour

Accepted Answer

The interdisciplinary field that studies the influence of inherited traits on complex behavior is behavioral genetics. This field combines elements of genetics, psychology, and biology to explore how genes, environment, and behavior interact to shape an individual's behavior. Choice A, cross-cultural anthropology, is not relevant to this field. Choice C, physiological psychology, focuses on the biological factors that underlie behavior but does not specifically address inherited traits. Choice D, ethology, is the study of animal behavior in their natural habitats and also does not specifically focus on inherited traits.

Question 5

Shane and Blane are monozygotic twins.However,people seldom get the two brothers mixed up because Blane is almost two inches shorter than Shane.What can you conclude based on this evidence

Accepted Answer

Monozygotic twins have the same genotype since they come from one fertilized egg. However, environmental factors can play a role in influencing the expression of genes, leading to differences in phenotype. In this case, the difference in height between Shane and Blane is likely due to other factors such as nutrition, exercise, or hormones.

Question 6

Which gland secretes hormones associated with the development of secondary sex characteristics

Accepted Answer

The gland that secretes hormones associated with the development of secondary sex characteristics is the gonad. Specifically, in males, it is the testes that secrete testosterone, which is responsible for the development of male secondary characteristics like facial hair and a deepening voice. In females, it is the ovaries that produce estrogen, which plays a crucial role in the development of female secondary characteristics like breast enlargement and the widening of hips.

Question 7

How many possible combinations of chromosomes are possible when you combine one person's sperm with another person's egg

Accepted Answer

When combining one person's sperm with another person's egg, the total possible combinations of chromosomes is 70 trillion, or 246. This is because each person has 23 pairs of chromosomes that can be combined in multiple ways, resulting in a large number of possible combinations for each pair of chromosomes. The formula for calculating the number of possible combinations is 2^n, where n is the number of chromosome pairs. In this case, 2^23 pairs of chromosomes results in 70 trillion possible combinations.

Question 8

What is the genetic complement of all cells in the human body,except sex cells

Accepted Answer

The genetic complement of all cells (except sex cells) in the human body is 46 chromosomes (23 pairs). This includes two copies of each chromosome - one inherited from each parent. Choice A (23 chromosomes) is incorrect because that is the number of chromosomes found in sex cells (sperm or egg). Choice C (23 recessive genes and 23 dominant genes) is incorrect because genes are not always dominant or recessive, and the genetic complement of an individual's cells would not be described in terms of dominant/recessive genes. Choice D (46 pairs of chromosomes) is incorrect because while it is technically true that there are 46 pairs of homologous chromosomes in each cell (excluding sex cells), it is more commonly stated that there are 23 pairs of chromosomes.

Question 9

Which statement describes genes but NOT chromosomes

Accepted Answer

Genes are segments of DNA that are found in large numbers within chromosomes, and there are thousands of genes in each sperm or egg.

Question 10

What is the term for the specific pattern of genes that an individual inherits at conception

Accepted Answer

Genotype refers to the specific pattern of genes that an individual inherits at conception. This includes both dominant and recessive genes which can affect physical traits, personality traits, and susceptibility to certain diseases.

Question 11

Four sisters were all raised in the same household by parents who are very creative and artistic.Anna and Betty are the biological children of their parents,while Cassie and Deanna were adopted as infants into the family.Like their parents,Anna and Betty are artistically inclined and enjoy working on creative projects.Cassie and Deanna are not particularly interested in artistic endeavours even though they've received a lot of exposure to art and a lot of encouragement for creative work.Which conclusion would be reasonable if this pattern occurred in a variety of similar families

Accepted Answer

Genetic factors seem to have more influence than environmental factors in artistic interest, as evidenced by the biological children showing a similar interest to their parents, while the adopted children do not, despite being raised in the same environment.

Question 12

Some individuals reach puberty before others.Which glands would be important to examine if you wished to explore the role of the endocrine system in producing these differences

Accepted Answer

The gonads (testes in males and ovaries in females) are responsible for producing sex hormones such as testosterone and estrogen, which play a critical role in the onset of puberty. Therefore, examining the function and regulation of the gonads is important in understanding individual differences in the timing of puberty. The parathyroid, pancreas, and thyroid are important endocrine glands, but they are not directly involved in the onset of puberty.

Question 13

If a trait is described as polygenic,what does that mean

Accepted Answer

A polygenic trait is controlled by more than one pair of genes.

Question 14

What is determined at conception

Accepted Answer

Conception is when an egg cell is fertilized by a sperm cell, resulting in the formation of a zygote. The zygote carries genetic material from both parents and determines an individual's genetic makeup or genotype, including their physical and hereditary traits. Phenotype refers to the observable physical and behavioral characteristics of an individual resulting from the interaction of their genotype with the environment, while somatotype refers to a classification system based on body type and composition.

Question 15

How many chromosomes does a zygote contain

Accepted Answer

A zygote, formed by the fusion of an egg and a sperm, contains 23 pairs of chromosomes, totaling 46 chromosomes. Each parent contributes one set of 23 chromosomes, making up the pairs.

Question 16

Mary and Celine are identical twins who have been raised apart in separate adoptive homes.Mary has developed a psychological disorder,but Celine does not appear to have the same disorder.What does this evidence suggest

Accepted Answer

This evidence suggests that environmental factors have more influence than genetic factors in the development of the disorder, as the twins share the same genetics but have been raised in different environments, leading to different outcomes regarding the disorder.

Question 17

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.What does this suggest about the disorder if this pattern holds for other identical twins

Accepted Answer

Since Londra and Sondra are identical twins and share the same genetic makeup, the fact that only Londra developed a psychological disorder suggests that environmental factors, rather than genetic ones, have a more significant influence on the development of this disorder. Identical twins having different outcomes in terms of psychological disorders indicates the role of environmental differences in their development.

Question 18

Phong and Phan are identical twins who have been raised apart in separate adoptive homes.However,both brothers have developed the same psychological disorder.What does this evidence suggest

Accepted Answer

The fact that Phong and Phan are identical twins raised apart but both developed the same psychological disorder suggests that genetic factors play a significant role in the development of this disorder, indicating that genetics may have more influence than environmental factors in this case.

Question 19

Skin colour is determined by three to five gene pairs.Based on this information,what type of trait is skin colour

Accepted Answer

Skin colour is determined by multiple gene pairs, therefore it is a polygenic trait. Monogenic traits are determined by a single gene, while homozygous and heterozygous refer to the alleles present at a single gene locus.

Question 20

Which two individuals would we expect to have the greatest degree of phenotypic similarity

Accepted Answer

Monozygotic (identical) twins come from a single fertilized egg that splits into two embryos, so they have nearly identical genomes and therefore the greatest degree of phenotypic similarity.

Quiz 3: A: The Biological Bases of Behaviour