Unit 4 Review - Homeostasis

Mr. Andersen reviews homeostasis, covering feedback loops, behavioral and physiological responses, and regulation mechanisms like blood glucose and thermoregulation. He discusses the impact of biotic and abiotic factors, plant and animal defenses, and cell differentiation. The video concludes with environmental sensing and evolution, emphasizing natural selection.

What is the primary characteristic of a negative feedback loop?

• It amplifies changes away from a set point.

• It maintains stability by counteracting changes.

• It is less common than positive feedback loops.

• It only occurs in non-living systems.

Which of the following is an example of a positive feedback loop?

• Regulating blood glucose levels.

• Sweating to cool down the body.

• Childbirth contractions.

• Shivering to increase body temperature.

What is a behavioral response to cold temperatures in some animals?

• Vasodilation

• Vasoconstriction

• Hibernation

• Sweating

How does the body respond when blood glucose levels are too high?

• Secretes glucagon

• Increases glucose production

• Increases glycogen breakdown

• Secretes insulin

What role does the hypothalamus play in thermoregulation?

• It secretes insulin.

• It filters blood in the kidneys.

• It produces glucagon.

• It detects changes in body temperature.

What is the primary function of the kidney in osmoregulation?

• To filter blood and regulate osmolarity

• To secrete glucagon

• To produce insulin

• To control body temperature

Which of the following is a biotic factor affecting homeostasis?

• Temperature changes

• Carbon dioxide levels

• Reintroduction of wolves

• Water availability

How do plants typically respond to an invading pathogen?

• By producing specific antibodies

• By hardening cells around the infection

• By increasing blood glucose levels

• By secreting insulin

What is the process called when a cell decides its specific function?

• Apoptosis

• Differentiation

• Osmoregulation

• Thermoregulation

How do plants determine the right time to flower?

• By using phytochromes to measure night length

• By detecting temperature changes

• Through circadian rhythms

• Through phototropism