Unit 8 Flashcards
Gland
- an organ that synthesizes (makes) substances
ex. hormones
Hormone
- a chemical substance produce in the body that regulates and controls a range of
bodily functions
Secrete
to produce and discharge a substance, especially from the cells of specialized
glands
Homeostasis
- the tendency of the body to regulate its internal conditions, usually by a
system of feedback controls
Target Cell
- a unique cell which does a specific job when a specific hormone attaches to it
Receptor
a specific site on a cell designed to recognize and accept the specific hormone
The Role of Hormones:
- Maintain homeostasis
- Release of most hormones occurs in short bursts, although some are secreted over
long periods of time in order to stimulate permanent changes in the body - Hormones only affect specific target cells by chemically binding to specific receptors
- Hormones regulate and coordinate a range of bodily functions
Circulating hormones
- travel around the body in the bloodstream delivering messages to
cells to perform a function which will help the body return to homeostasis (ex. adrenaline
and testosterone)
Local Hormones
- act on neighbouring cells without entering the bloodstream and are
usually inactivated quickly (ex. insulin and glucag)
Hypothalamus gland function
Regulates hunger. thirst, sleep and wakefulness plus most of your
involuntary mechanisms including body temperature
THYROID
GLANDS
Regulates your energy and your
metabolism
PANCREAS
Aids in the digestion of protein, fats and carbo- hydrates. Produces insulin which controls blood sugar levels.
Ovaries
Influences how your blood circulates and determines your mental vigor
and your sex drive (Testes in males.)
ADRENAL
GLANDS
ADRENAL GLANDS Secretes hundreds of compounds including cortisone & adrenaline which helps you react to 110. emergencies Regulates your metabolic processes in the cells, water balance, blood pressure etc
THYMUS
Helps build resistence to disease.
PARATHYROID
Secretes the hormones necessary for calcium absorption.
PITUITARY
GLAND
Controls all other endocrine glands influences growth, metabolism and
regeneration.
Metabolism
The conversion of nutrients into energy and building materials to meet your body’s needs
Local hormone example
Pancreas release glucagon, this causes liver to release glucose into the blood. Causing increased blood glucose levels, if too high blood glucose levels, this causes insulin release, which causes liver to take glucose out of blood and store it as glycogen, this causes lower blood glucose level, cuasing release of glucagon.
REGULATION OF CIRCULATING HORMONES
egulated through a «negative» feedback loop mechanism ✔
regulated by signaling from the nervous system «adrenaline» ✔
regulated by the chemical changes in the blood «insulin» ✔
Explain the relationship between the hypothalamus and the pituitary gland
Neuro-hormones such as Growth Hormone Releasing Hormone (GHRH) are produced in the Hypothalamus
They travel down the nerve cells into the pituitary gland.
This causes the Pituitary to release Growth Hormone (GH)
The hypothalamus makes some of its own hormones such as Anti-Diuretic Hormone (ADH)
They travel down the nerve cells into the pituitary gland.
They are released directly into the blood stream from here.
The hypothalamus and the pituitary gland work together to maintain homeostasis
The hypothalamus is the part of the brain that controls the pituitary gland
The pituitary gland as the master gland, as it sends hormones to other glands in the body to release their hormones.
