AP BIOLOGY

Detailed explanation-1: -Animal organs and organ systems constantly adjust to internal and external changes through a process called homeostasis (“steady state”). These changes might be in the level of glucose or calcium in blood or in external temperatures. Homeostasis means to maintain dynamic equilibrium in the body.

Detailed explanation-2: -A stimulus is a change in the internal or external environment. A receptor detects a stimulus. A coordinator formulates a suitable response to a stimulus. An effector produces a response.

Detailed explanation-3: -Receptors are the cells that detect the changes in chemical and physical conditions of the external and internal environment of an animal.

Detailed explanation-4: -Organisms need to detect and respond to changes in their internal and external environment. This is because the conditions inside our body must be carefully controlled for it to function effectively and survive. The control systems that allow organisms to respond to changes are incredibly important.

Detailed explanation-5: -This response, or behavior, is called a tropism.