PSYCH 111: Introduction to Psychology: Week 7: Chapter 3 Quizzes: Biopsychology

The Correct Answer is:

d. glucagon and insulin

The pancreas plays a vital role in regulating blood sugar levels by secreting two key hormones: insulin and glucagon. Insulin lowers blood glucose by promoting its uptake into cells for energy or storage, while glucagon raises blood glucose by stimulating the liver to release stored glucose. Together, they maintain homeostasis of blood sugar levels, ensuring the body has a stable energy supply necessary for proper functioning.

Why the other options are incorrect:

a. estrogen and progesterone

This is incorrect because these hormones are secreted by the ovaries in females, not the pancreas. They regulate female reproductive functions, including the menstrual cycle and pregnancy.

b. norepinephrine and epinephrine

This is incorrect because these hormones are secreted by the adrenal glands, not the pancreas. They prepare the body for fight-or-flight responses during stress by increasing heart rate, blood pressure, and energy release.

c. thyroxine and oxytocin

This is incorrect because thyroxine is secreted by the thyroid gland to regulate metabolism, while oxytocin is produced by the hypothalamus and released by the pituitary gland to influence childbirth, bonding, and social behaviors.

The Correct Answer is:

B. Because electrical impulses travel along the axon, while neurotransmitters cross the synaptic gap

Neuronal communication is considered an electrochemical event because it involves two interconnected processes. The electrical process begins when an action potential travels along the axon, caused by ion exchange across the neuron’s membrane. When this electrical signal reaches the axon terminal, it triggers the release of neurotransmitters into the synaptic cleft. These neurotransmitters then bind to receptors on the next neuron, allowing the signal to continue. Both electrical and chemical steps are essential for proper communication.

Why the other options are incorrect:

A. Because the brain uses only neurotransmitters to send messages between neurons

This is incorrect because neurotransmitters alone cannot transmit signals without the initial electrical impulse traveling along the axon. The electrical action potential is what triggers the release of neurotransmitters, making both electrical and chemical processes necessary for communication.

C. Because neurons communicate using hormones released into the bloodstream

This is incorrect because hormones are part of the endocrine system and are not the primary method of neuron-to-neuron communication. Hormonal signaling is much slower and affects multiple systems, whereas neurotransmitter-based signaling is rapid, precise, and specifically designed for quick communication between neurons.

D. Because communication in neurons relies entirely on electrical charges without chemical involvement

This is incorrect because although the action potential is electrical, the signal cannot cross the synaptic cleft without neurotransmitters. The chemical process bridges the gap between neurons, making the chemical phase just as vital as the electrical one in maintaining proper signal transmission.

The Correct Answer is:

C. Epigenetics

Epigenetics is the field of study that explores how environmental factors influence gene expression without altering the DNA sequence itself. It examines how experiences, diet, stress, toxins, and other external factors can “switch” genes on or off, leading to differences in traits and behaviors. Epigenetic mechanisms, such as DNA methylation and histone modification, explain how individuals with the same genotype can develop different phenotypes. This field bridges genetics, psychology, and environment in understanding human development and health.

Why the other options are incorrect:

A. Social psychology

This is incorrect because social psychology focuses on how people’s thoughts, behaviors, and emotions are influenced by others and social contexts. It does not study genes or their expression.

B. Evolutionary psychology

This is incorrect because evolutionary psychology studies how behaviors and mental processes evolved over time to enhance survival and reproduction. While related to genetics, it does not focus on gene expression specifically.

D. Behavioral neuroscience

This is incorrect because behavioral neuroscience studies the relationship between the brain, nervous system, and behavior. While it looks at biological processes, it does not primarily examine how environmental factors regulate gene expression like epigenetics does.

The Correct Answer is:

B. Our genes influence the environments we experience, and our environments influence how our genes are expressed

Genetic-environmental correlation explains the reciprocal relationship between genes and the environment. Our genes can shape the kinds of environments we are exposed to, and in turn, those environments can activate, enhance, or suppress the expression of certain genes. For example, a child genetically predisposed to musical talent may seek environments rich in music, such as lessons and performances, which further develop their abilities. This constant interaction between genetics and environment shapes personality, intelligence, skills, and behavior.

Why the other options are incorrect:

A. Our environment determines our traits completely, and genes have no influence

This is incorrect because traits result from an interaction between genes and environment. Genes set biological potentials, which the environment helps shape.

C. Genes and environment function separately and do not affect one another

This is incorrect because research shows that genes and environment are interdependent. Genes influence environments we select, and environments, in turn, affect gene expression.

D. Environmental factors can override our genetic makeup and permanently replace inherited traits

This is incorrect because the environment cannot replace or rewrite genes. Instead, it influences how genes are expressed, not the genetic code itself.

The Correct Answer is:

d. thalamus

The thalamus, located in the center of the brain, acts as a sensory relay station. It receives sensory input from the eyes, ears, skin, and taste receptors, then directs this information to the appropriate regions of the cerebral cortex for further processing. The only exception is the sense of smell, which bypasses the thalamus and goes directly to the olfactory cortex. The thalamus plays a critical role in regulating sensory perception, attention, and consciousness.

Why the other options are incorrect:

a. amygdala

This is incorrect because the amygdala is primarily involved in processing emotions such as fear and aggression, not relaying sensory information to the cortex.

b. hippocampus

This is incorrect because the hippocampus is responsible for forming and consolidating explicit memories and spatial navigation, not directing sensory signals.

c. hypothalamus

This is incorrect because the hypothalamus regulates homeostasis by controlling body temperature, appetite, hormone release, and other automatic bodily processes. It does not serve as the brain’s main sensory relay station.

The Correct Answer is:

B. It regulates homeostasis, controls appetite, body temperature, and connects the nervous and endocrine systems

The hypothalamus is a small but crucial structure located at the base of the brain that plays a central role in maintaining homeostasis — the body’s internal balance. It regulates vital processes like body temperature, hunger, thirst, and blood pressure. Additionally, it acts as a bridge between the nervous and endocrine systems by controlling the pituitary gland, influencing hormone release. It also plays a significant role in regulating sexual motivation, emotional responses, and behavior.

Why the other options are incorrect:

A. It processes visual information and interprets color and motion

This is incorrect because visual processing occurs in the occipital lobe, not the hypothalamus. The hypothalamus focuses on maintaining the body’s internal balance, whereas the occipital lobe interprets images and motion from visual input.

C. It manages voluntary muscle coordination and problem-solving skills

This is incorrect because muscle coordination is primarily controlled by the cerebellum, while decision-making and problem-solving are functions of the frontal lobe. The hypothalamus instead regulates automatic, involuntary functions related to survival and hormonal balance.

D. It stores long-term memories and processes auditory information exclusively

This is incorrect because long-term memory storage is handled by the hippocampus, and auditory processing occurs in the temporal lobe. The hypothalamus is responsible for regulating physiological states and connecting the nervous system with the endocrine system, not managing memory or hearing.

The Correct Answer is:

B. It is the process by which the nervous system changes and adapts based on experiences

Neuroplasticity is the brain and nervous system’s remarkable ability to reorganize and adapt in response to personal experiences, learning, injuries, and developmental processes. It involves forming new neural pathways, strengthening existing connections, or even compensating for damaged areas of the brain. This flexibility allows individuals to acquire new skills, recover from injuries, and adapt to environmental changes, making neuroplasticity a fundamental process in growth and learning throughout life.

Why the other options are incorrect:

A. It refers to the brain’s inability to change after childhood development

This is incorrect because neuroplasticity shows that the brain remains capable of change throughout life. While plasticity is more robust in childhood, adults also form new connections and reorganize neural pathways based on learning, practice, and recovery from damage.

C. It describes how neurotransmitters permanently block communication between neurons

This is incorrect because neurotransmitters facilitate communication between neurons rather than permanently blocking it. Neuroplasticity focuses on structural and functional adaptations in the nervous system, not on shutting down neurotransmitter activity or preventing neuron-to-neuron signaling

D. It explains why the spinal cord controls only reflexive and fixed responsesThis is incorrect because neuroplasticity goes beyond reflexive actions managed by the spinal cord. While reflexes are mostly automatic, neuroplasticity involves higher-level brain functions and allows new neural pathways to develop, enabling learning, skill-building, and adaptation to changing environments.

The Correct Answer is:

B. It shows changes in metabolic activity over time by tracking blood flow in the brain

Functional magnetic resonance imaging (fMRI) is a non-invasive brain imaging technique that measures changes in blood oxygen levels to track metabolic activity over time. When a specific brain region becomes active, it requires more oxygen, increasing blood flow to that area. The fMRI detects these changes, allowing researchers to create real-time maps of brain activity during different tasks. Unlike PET scans, fMRI does not involve radiation and provides better resolution and timing accuracy.

Why the other options are incorrect:

A. It measures electrical activity in the brain by detecting neuron firing patterns

This is incorrect because measuring electrical activity is the role of electroencephalography (EEG), not fMRI. While fMRI detects blood flow linked to activity, it does not directly measure neuron firing.

C. It uses radioactive tracers to map active and inactive brain regions

This is incorrect because the use of radioactive tracers is a feature of positron emission tomography (PET) scans. fMRI, on the other hand, measures oxygenated blood flow without exposing the brain to radiation.

D. It captures static images of brain structures without showing brain function

This is incorrect because static structural imaging is the function of a traditional MRI, not fMRI. While both techniques use magnetic resonance, fMRI specifically shows dynamic changes in brain activity over time rather than just capturing anatomical images.

The Correct Answer is:

B. It examines how gene-environment interactions can cause the same genotype to produce different phenotypes

Epigenetics is the study of how environmental factors influence gene expression without changing the DNA sequence itself. It explains how individuals with the same genotype can display different phenotypes based on experiences, lifestyle, diet, stress, and other environmental exposures. Epigenetic changes occur through mechanisms like DNA methylation and histone modification, which switch genes “on” or “off.” This field highlights the dynamic relationship between biology and environment in shaping traits, behaviors, and susceptibility to psychological and physical disorders.

Why the other options are incorrect:

A. It studies how genes alone determine fixed traits without environmental influence

This is incorrect because epigenetics specifically focuses on how environmental factors interact with genes. Traits are not determined by DNA alone; environmental triggers can alter how genes are expressed without changing the genetic code itself.

C. It focuses only on inherited mutations that permanently alter the DNA sequence

This is incorrect because mutations change the DNA structure itself, while epigenetics involves reversible changes in gene expression. Epigenetic mechanisms affect whether genes are activated or silenced but do not permanently rewrite the DNA sequence.

D. It explains how hormones regulate reproduction and sexual development exclusively

This is incorrect because hormonal regulation is a function of the endocrine system, not epigenetics. While hormones can influence gene activity, epigenetics studies the broader effects of environmental and lifestyle factors on how genes are expressed across multiple biological systems.