Question 1

The folds of the cerebral cortex

Accepted Answer

The folds of the cerebral cortex, also known as convolutions or gyri, allow for more cortex to be packed into a smaller area, increasing the brain's surface area and capacity for processing information. This is important in allowing for the higher order thinking and cognitive functions that the brain is capable of.

Question 2

Which area of the brain is involved in memory processes?

Accepted Answer

The hippocampus is a region of the brain located in the temporal lobe that plays a critical role in the formation and storage of new memories. Damage to the hippocampus can result in various forms of memory impairment, such as anterograde amnesia, where individuals cannot form new memories.

Question 3

In regard to the chromosomes that parents pass on to their offspring, parents pass on

Accepted Answer

Chromosomes are randomly assorted during meiosis and experience crossing over, which can create new combinations of alleles. Therefore, offspring receive chromosomes that are constituted differently than their parents' chromosomes. This is why siblings can have different combinations of traits and genetic disorders than each other or their parents.

Question 4

Humans continue to generate new neurons throughout life, particularly in the

Accepted Answer

The hippocampus is a region of the brain important for memory and learning, and it is known for its ongoing production of new neurons, particularly in the dentate gyrus. This process, known as neurogenesis, continues throughout adulthood, although it may decline with age.

Question 5

Different forms of a gene are referred to as

Accepted Answer

Different forms of a gene are referred to as alleles.

Question 6

During which time is brain damage LEAST likely to lead to permanent deficiencies?

Accepted Answer

During early childhood, the brain has a high level of plasticity, which allows it to recover and reorganize more effectively after damage compared to other stages of life.

Question 7

Individuals receive _____ copy(ies) of each gene from their mother.

Accepted Answer

Individuals receive one copy of each gene from their mother and one copy from their father, making a total of two copies for each gene.

Question 8

Genes guarantee that humans will be similar to each other in certain ways. What are these?

Accepted Answer

Genes ensure similarity among humans both at the species level, by determining shared characteristics that define Homo sapiens, and at the individual level, by influencing unique traits that differentiate one person from another.

Question 9

Which occurrence is NOT likely to be due to environmental factors?

Accepted Answer

Females generally reaching puberty before their male peers is a biological phenomenon largely determined by genetics and the inherent differences in the physiological development between males and females, rather than environmental factors.

Question 10

How does neurogenesis occur?

Accepted Answer

Neurogenesis occurs through cell division, where new neurons are generated from neural stem cells or progenitor cells.

Question 11

The amount of variability of a trait that is due to genetic and environmental factors is referred to as

Accepted Answer

Heritability is the proportion of variability in a trait that is due to genetic factors. Environmental factors also contribute to the variability of a trait, so heritability reflects the extent to which genetics vs. environment contribute to that variability.

Question 12

Which statement provides the BEST evidence for the argument that intelligence has a genetic influence?

Accepted Answer

The statement that identical twins are more similar in intelligence than fraternal twins suggests a genetic influence on intelligence, as identical twins share 100% of their genes while fraternal twins share, on average, only 50%. This supports the idea that genetics play a significant role in determining intelligence.

Question 13

Synaptic pruning refers to which process?

Accepted Answer

Synaptic pruning refers to the elimination of unnecessary or weaker connections between neurons in the brain. This process helps to refine the neural circuitry and enhance overall brain function.

Question 14

Which method for examining the specific areas of the brain associated with particular behaviors, thoughts, and feelings is MOST likely to be used with infants and young children?

Accepted Answer

Electrophysiological recording is the most appropriate method for examining specific brain areas in infants and young children because it is noninvasive and does not require the child to remain still. This method involves placing electrodes on the scalp to measure electrical activity in the brain. PET and fMRI scans require the child to remain still and are not always suitable for young children. Autopsy is not a viable option for examining brain activity in living individuals.

Question 15

Eddie and Freddy are identical twins who grew up in the same home but then went their separate ways after high school. Eddie moved to the Midwest and became a family farmer. Freddy moved to New York City and became a high-powered attorney. A university research project measures their DNA methylation levels at age 6, age 36, and age 60. Which statement MOST likely reflects the results?

Accepted Answer

Although Eddie and Freddy have identical DNA, their different lifestyles and environments could cause epigenetic changes that affect their DNA methylation levels. Since Eddie is a farmer and lives in the Midwest, he may be exposed to different environmental factors than Freddy, who is an attorney and lives in New York City. Additionally, their different lifestyles and diets could contribute to differences in their methylation levels over time. However, since they are identical twins, their methylation levels at age 6 should be similar. As they age and are exposed to different environments and lifestyles, their methylation levels may diverge.

Question 16

Kody, a boy, and Shakira, a girl, are brother and sister. They both inherit the same recessive allele for trait T on their X chromosome from their mother. What is the relative likelihood of Kody and Shakira expressing trait T?

Accepted Answer

Kody has only one X chromosome (XY), so if he inherits a recessive allele for trait T from his mother, he will express it because he lacks a second X chromosome that could potentially carry a dominant allele to mask the recessive one. Shakira, on the other hand, has two X chromosomes (XX), so she would need to inherit the recessive allele for trait T from both parents to express the trait. Therefore, Kody is more likely to express trait T than Shakira.

Question 17

Which statement about physical growth is TRUE?

Accepted Answer

Physical growth is not regular over time; it is uneven. There are periods of rapid growth, followed by periods of slower growth, and sometimes even regression. This is particularly true during infancy, where growth tends to be the most rapid, followed by childhood and adolescence where there are also bursts of growth. It is also important to note that growth is uneven across different parts of the body, with some areas growing more quickly than others. Human beings actually grow for a larger proportion of their life span than do other species, so option B is also incorrect. Option A is therefore incorrect, leaving only option D as the correct choice.

Question 18

Which statement about sex determination is TRUE?

Accepted Answer

The presence of a Y chromosome makes an individual male. The Y chromosome carries the SRY gene which stimulates the development of male characteristics. Females typically have two X chromosomes.

Question 19

Traits that are influenced by genetic factors are considered

Accepted Answer

Traits that are influenced by genetic factors are heritable, meaning they can be passed down from parents to offspring through their genes.

Question 20

Infant taste preferences

Accepted Answer

Research suggests that infant taste preferences are innate and may be related to evolution and survival instincts. Infants have a preference for sweet flavors and a dislike for bitter flavors, which may help them identify and prefer nutrient-dense breast milk over potentially harmful substances. Adult taste preferences may be more influenced by environmental and cultural factors.

Quiz 3: Biology and Behavior