Biological explanations of obesity

which BMI would be considered the benchmark for obesity?

• 25

• 30

• 35

• 40

Concordance rates for obesity ranged from __________ which demonstrates a very substantial genetic component to obesity that remained influential from late childhood through adolescence to adulthood.

• 30-60%

• 60%-70%

• 61%-80%

• 72%-92%

The action of genes on obesity is (a)   . This means that, genetic inheritance involves multiple genes, their effects, interacting with eachother.

there is no single genetic cause of obesity. Many genes involved, all with relatively small effects.

• true

• false

Most research studies of both humans and non-human animals show that obesity is associated with abnormally ____________ levels of serotonin (or its main metabolite 5-HIAA).

• low

• high

It is _________ that signals to the hypothalamus that we have eaten to satiety.

• serotonin

• dopamine

Low __________ levels lead to cravings for carbohydrates, energy dense foods, including sugars, causing weight gain through too many calories.

• serotonin

• dopamine

Normal levels of this neurotransmitter stimulate brain areas such as the hypothalamus, hippocampus and amygdala, providing rewarding feelings of pleasure and well being.

• serotonin

• dopamine

Because levels of_______ are so low in some people, the neurotransmitter cannot perform its usual pleasurable reward function in response to eating i.e a person does not feel good after eating.

• serotonin

• dopamine

Overeating can therefore be seen as an attempt to activate reward centres in the brain that provide feelings of pleasure by increasing _______ levels.

• serotonin

• dopamine