Biology Unit 2 Homeostasis

Which type of receptor detects only intense (painful) chemical, mechanical or thermal stimulation?

• nociceptor

• chemoreceptor

• mechanoreceptor

• photoreceptor

Which type of receptor detects only light stimulation?

• nociceptor

• chemoreceptor

• mechanoreceptor

• photoreceptor

Muscle fibre cells are effectors contract in response to which type of stimulus:

• Nerve impulse from a sensory neuron

• The hormone insulin binding to a hormone protein receptor

• Nerve impulse from a motor neuron

• The hormone adrenaline binding to a hormone protein receptor

Identify the correct sequence of a nerve impulse from receptor to effector

• Receptor > motor neuron > interneuron > sensory neuron > effector

• Receptor > motor neuron > sensory neuron > interneuron > receptor

• Receptor > sensory neuron > interneuron > motor neuron > effector

• Receptor > interneuron > sensory neuron > motor neuron > receptor

Examine the diagram showing the action potential of a nerve impulse along the axon of neuron. Which of the following describes step 4?

• Resting potential

• Peak of action potential

• Repolarisation

• Depolarisation

Which of the following statements about hormones is false?

• Hormones are mostly produced in endocrine glands

• Hormones are chemical messengers

• Hormones can relay their message to any hormone protein receptor in the body

• Hormones are transported throughout the body via the circulatory or lymphatic system.

Which of the following statements about hormones is false?

• Upregulation occurs when a cell is stimulated to produce more of a specific cellular component

• A decrease in the number of protein receptors for a specific hormone results in upregulation

• When a hormone binds to its protein receptor, it stimulates the cell to produce more of the receptor

• Hormones can only bind to their specific, corresponding protein receptor

Which of the following statements about thermoregulation is false?

• Some types of insulation can reduce heat loss in cold environments, and other types of insulation can reduce heat gain in hot environments

• Endotherms are animals that regulate their internal body temperature

• Endotherms living in cold environments tend to have a high surface area to volume ratio

• Brown adipose tissue contains more mitochondria and blood vessels than white adipose tissue

Examine the graph showing the effect of environmental temperature on the metabolic rate of a small mammal. Which of the following temperature ranges corresponds to an increase in thermoregulatory responses that reduce internal body temperatures?

• 28^oC - 36^oC

• less than 28^oC

• greater than 36^oC

• less than 36^oC

Which of the following physiological thermoregulatory mechanisms is an adaptation to hot conditions?

• Vasoconstriction

• Counter-current heat exchange

• Shivering

• Evaporative heat loss