1 Serous fluid is contained between the visceral pleura and

1. Serous fluid is contained between the visceral pleura and the lung.

True

False

2. When blood sugar levels increase after a meal, insulin is released. This lowers sugar levels back toward normal. This is an example of

negative feedback.

positive feedback.

3. During childbirth, the baby pushes on the wall of the uterus. This is detected by pressure receptors that signal the brain to release oxytocin. If this is a positive feedback process, select the likely next step.

Oxytocin causes the uterus to contract, preventing further release of oxytocin from the brain.

Oxytocin has no effect on the uterus, so as to maintain homeostasis.

Oxytocin causes the uterus to relax, decreasing pressure from the baby so as to maintain homeostasis.

Oxytocin causes the uterus to contract, further stimulating the receptors, and releasing more oxytocin from the brain.

4. Which of the following is NOT an example of homeostasis?

Maintaining body temperature by putting on a hoodie

Maintaining body temperature by sweating

Maintaining blood pH by hyperventilating

Maintaining blood glucose levels by releasing insulin

5. Thermoreceptors detect body temperature and send impulses to the brain for analysis. If body temperature is low, the brain will signal skeletal muscles to perform brief, repeated contractions to help generate heat. In this example, what is the effector?

Skeletal muscles

Body temperature

Brain

Thermoreceptors

Solution

1. False

Serous fluid is present in between visceral pleura and parietal pleura.

2. Negative feedback

3. Oxytocin causes the uterus to contract, further stimulating the receptors, and releasing more oxytocin from the brain.

4. Maintaining body temperature by putting on a hoodie.

5. Skeletal muscles

Effector organs are those which respond to the nerve impulses fron CNS.