What are two examples of how the human body maintains homeostasis, what is the process called when glucose is broken down to make ATP, and how do cacti and other plants respond to stimuli?

What these questions are really asking

You are being asked to connect three big biology ideas: how humans keep internal conditions stable (homeostasis), how cells harvest energy from food (ATP production), and how plants sense and react to their environment (stimulus and response).

Two clear examples of homeostasis in the human body

Homeostasis means keeping internal conditions within a safe range using feedback control.

• Body temperature control (thermoregulation): If you get too warm, you sweat and blood vessels near the skin widen to release heat. If you get too cold, you shiver and blood vessels narrow to reduce heat loss.
• Blood glucose control: After a meal, the pancreas releases insulin, which helps cells take in glucose and store it as glycogen, lowering blood sugar. Between meals, glucagon signals the liver to release glucose, raising blood sugar.

These are classic examples of negative feedback, where the body pushes a change back toward a set point.

Name of the process that breaks down glucose to make ATP

The overall energy-releasing pathway is cellular respiration.

A common summary equation is: $$C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{ATP (energy)}$$

Cellular respiration includes stages such as glycolysis and (when oxygen is present) aerobic steps in mitochondria that make most of the ATP.

How cacti and other plants respond to stimuli

Plants do not have nerves, but they still detect stimuli and respond using hormones and growth or movement responses.

• Tropisms (growth responses): Plants can grow toward light (phototropism) or respond to gravity (gravitropism).
• Water-saving responses in cacti: Cacti often reduce water loss by controlling stomata (tiny pores). Many use CAM photosynthesis, opening stomata mostly at night to limit evaporation during hot days.

So, plant responses often show up as changes in growth direction, opening and closing stomata, or other hormone-driven adjustments.