HAP1.3

If the environment gets cold, we will often shiver in order to:

• keep body temperature the same as the external temperature

• decrease body temperature

• increase body temperature

• regulate blood pressure

Homeostasis

• allows for a wildly fluctuating internal environment

• is impossible in vertebrates

• is the maintenance of a relatively stable internal environment and often incorporates a form of feedback regulation

• is the maintenance of a relatively stable internal environment and often incorporates a form of feedback regulation

The organ/cells that carry out the response

• control center

• receptor

• thermoregulation

• effector

Humans have ___ for body temperature, blood glucose concentrations, electrolyte concentrations, pH levels, tendon tension and variables.

• positive feedback mechanisms

• a narrow range of healthy values

• a wide range of healthy values

• no regulation

When training a dog, you might reward the dog for obeying your command. This increases the likelihood that the dog will again obey that command in the future. This is similar to a

• positive feedback loop

• negative feedback loop

When glucose levels in the blood rise, your brain sends a signal to your pancreas. The pancreas releases insulin, which opens channels in cell membranes to allow glucose to enter the cell, lowering blood sugar levels.

• Positive Feedback Response

• Negative Feedback Loop

When you get cut, your skin cells release hormones that signal platelets to come and stop the bleeding. Platelets then release more hormones that signal even more platelets to help stop bleeding. The hormone signals continue until the cut is closed.

• Positive Feedback Response

• Negative Feedback Loop

The "cause" for something to happen is the

• response

• effect

• stimulus

• homeostasis

If the calcium in your blood decreases below homeostasis levels, a gland in the brain will sense the decrease and send a chemical message to your bones. Your bones will release calcium into the blood, bringing blood calcium levels back up.

• Positive Feedback Response

• Negative Feedback Loop

The two types of feedback systems that help organisms maintain homeostasis are:

• positive and negative

• receptor and effector

• static and dynamic

• minor and major