Homeostasis and Regulation Biology exam revision

Flashcards covering vocabulary terms related to Homeostasis and Regulation

Homeostasis

The tendency for an organism or cell to maintain a constant internal environment within tolerance limits, despite changes to the external environment

Hormones

Chemical messengers produced in endocrine glands and released directly into the bloodstream to be transported to specific target cells where they elicit a response

Antagonistic hormones

A pair of hormones that have opposing effects on one another, such as insulin and glucagon

Pituitary gland

Secretes hormones involved in regulation of growth, reproduction, kidney function and thyroid and adrenal activity

Hypothalamus

The section of the brain that links the nervous and endocrine systems in order to maintain homeostasis

Negative feedback

Reverses the change detected to promote equilibrium

Positive feedback

Continues and reinforces the change detected, amplifying the initial change until the stimulus is removed

Efferent (motor neurons)

Transmit info from CNS to tissues and organs

Afferent (sensory neurons)

Communicate info from tissues and organs to CNS

Receptor

Detects change

Control center

Takes in the message and relays the information to the appropriate regulator, usually the brain

Effector

Muscles and organs that receive signals from the brain and help restore normal balance

Thermoregulation

Process that allows your body to maintain its core internal temperature

Vasodilate

Blood vessels under the skin get wider, increasing blood flow to the skin where it is cooler to release heat through heat radiation

Vasoconstrict

Blood vessels under the skin become narrower, decreasing blood flow to the skin, retaining heat near the warm inner body

Thermogenesis

Produce heat, such as muscles shivering

Hormonal Thermogenesis

Thyroid gland releases hormones to increase metabolism, increasing energy and heat production

Osmoregulation

Process of maintaining an internal balance of salt and water

Anti-diuretic hormone (ADH)

Released to hold onto water and decreases urine production