Explanation:

Choice A is correct because fraternal twins only share 50% of their genes, and identical twins share 100%. Due to this, researchers can study the differences and similarities in personality, intellect, and behaviour.

Choices B, C, and D are incorrect because they do not address the nature aspect of the nature vs. nurture debate in twin studies.

Explanation:

Stress hormones such as adrenaline and cortisol released after an event activates the amygdala often linked to the formation of flashbulb memories.

Choices B, C and A are hormones but are not related to the amygdala.

Explanation:

Answer C is correct because the study mainly focused on the heritability of intelligence and the influence of upbringing.

Answers A, B, and D are incorrect because the study did not specifically focus on birth order, cultural factors, or physical health outcomes.

Explanation:

A transporter protein is a protein at a synapse that recognises neurotransmitter molecules and collects them to transport them somewhere (often back to the presynaptic neuron) where they can be degraded, recycled, or re-used. A, describes the process of neurotransmission, C, is the axon terminal and D, is the crossing of the synapse during neurotransmission.

Explanation:

The evolutionary approach, using Charles Darwin’s concepts of evolution and adaptation, suggests that our ability to adapt to new situations and environments directly results from evolution.

Answer A is incorrect because humanistic psychology emphasises achieving a person’s holistic growth in terms of love, fulfilment, and self-worth.

Answer B is incorrect because the Freudian concept of psychoanalytic psychology emphasises the influence of the unconscious and childhood experiences on behaviour and personality.

Answer D is incorrect because the biopsychosocial perspective suggests that physical and mental health is affected by biology, psychology, and social stressors.

Explanation:
Studying animal models refer to using animals in research to test a cause-effect hypothesis about a specific human behaviour—for example, understanding stress models, separation models, and medical models. They allow researchers to test hypotheses and explore interventions in a controlled and ethical manner.

Popular species commonly subjected to psychological research are rats, mice, pigeons, cats, rabbits, hamsters, dogs, chimpanzees, and baboons.

Explanation:
Cushing's syndrome is a medical condition that occurs when the body is exposed to high cortisol levels for an extended period. This can be because the body is making too much cortisol or because of oral corticosteroid medicines.

Cushing's syndrome symptoms can include feeling emotional and tired, a rounded face, high blood pressure, and excess weight around the shoulders and neck.

Explanation:

A, B and D are functions of the MRI and fMRI.

The difference between the MRI and fMRI is C, the ability to produce a video representation of brain activity over time, which a normal MRI cannot do.

MRI scans use magnetic fields and radio waves to produce 3D computer-generated images.

Explanation:
Serotonin is a neurotransmitter responsible for regulating essential bodily functions, including mood, sleep, and learning and memory processes. It acts as a chemical messenger and passes messages from the brain to the rest of the body. Serotonin deficiency can result in depressive symptoms and anxiety in people.

Explanation:
SSRIs (selective serotonin reuptake inhibitors) are drugs that act as agonists/antagonists. SSRIs selectively inhibit or block the reuptake of the neurotransmitter serotonin from the synaptic gap, increasing serotonin concentration in the synapse. SSRIs allow serotonin to build up between neurons so messages are sent correctly.

Explanation:
The primary role of GABA (gamma-aminobutyric acid) is to send inhibitory signalling to the brain and reduce the effect of the excitatory neurotransmitter. It promotes relaxation by inhibiting the neurons from firing and balancing brain activity.

Explanation:
Research on depression suggests that heritability of depression is a result of both genetic and environmental factors (Caspi et al., 2003). Genetic factors contribute to individual differences in depression, and environmental factors contribute.

Explanation:
The 5-HTT or serotonin receptors are found in the central or peripheral nervous system. 5-HTT stands for 5-hydroxytryptamine. Serotonin receptors affect many processes, such as memory, sleep, appetite, aggression, and anxiety. A study done by Caspi et al. in the year 2003 shows depression was also linked to a particular gene—the serotonin transporter gene 5-HTT.

Explanation:
Synaptogenesis is an explosion of synaptic formation between neurons during early brain development. The brain experiences a lot of growth during infancy. This period of synaptogenesis plays an essential role in learning, memory formation. Active synapses are strengthened, and less active synapses are weakened. The process of removing the irrelevant/pruned synapses is referred to as synaptic pruning.

Explanation:
Behavior results from genetic factors and natural selection. The evolutionary explanation of behaviour explains that certain behaviours have lasted over many generations (i.e. survival tendency) and, as a result, have been encoded in the genes of organisms. They are subject to natural selection.

Explanation:

The biological approach in understanding human behaviour emphasises the role of genetics and other physiological factors in influencing personality and behaviour. Answers A, B, and C do not have this emphasis.

Explanation:
Cortical remapping, or cortical reorganization, is the ability of one part of the brain area to assume the functions of another part of the brain in case of an injury.

Cortical remapping is explained in the research by Merzenich et al. (1984) on eight adult owl monkeys. The middle finger of the monkey was amputated, and remapping was observed in 62 days. Adjacent areas from other fingers spread and occupied the parts of the unused area / amputated area.

Explanation:

Answer A is correct. The behaviour the dogs exhibited after being repeatedly shocked showed they stopped trying to escape due to the shocks, thereby learning that they were helpless in that particular situation.

Explanation:
Antagonists counteract neurotransmitters and prevent a signal from being passed further. It decreases the activation of a synaptic receptor by blocking the neurotransmitters from binding/bonding. An example of an antagonist is scopolamine, which affects the neurotransmitter Acetylcholine (ACh).

Explanation:
EEG - Electroencephalography measures the electric potentials generated by the neural circuits; neurons here interact with each other by sending electrical impulses. In this method, electrodes are attached to the scalp and pick up the changes in the electric potential of the scalp areas. EEG has a perfect temporal resolution and can detect changes in brain activity within milliseconds. Because of this, it outperforms techniques such as fMRI.

Explanation:

An action potential, also called a nerve impulse, is an electrical charge that travels along the membrane of a neuron. It can be generated when chemical signals change a neuron’s membrane potential from a nearby cell. A, neurotransmission is the transfer of information between neurons. B, synaptic reuptake refers to the reabsorption of neurotransmitter molecules by the presynaptic neuron that released them and C, a receptor site, is the space on the cell that houses the receptor.

Explanation:

In neurological diseases, axons can regenerate or sprout in an attempt to reconnect with the target neuron and restore synapse function.

A is for synaptic plasticity, C is for synaptic pruning and D is about cortical remapping

Explanation:
Leptin is a hormone that travels from the fat cells to the brain indicating that enough food has been consumed and energy burning can happen at a normal rate.

When an individual is suffering from obesity, their bodies become resistant and no longer receive the message that their body has had enough food.