Chemical Regulation Endocrine System  Communication

Do Now Place Labs & Respiration Packet in TWO piles in the middle of the table What do you know about the endocrine system? Brain Pop video: Endocrine System Endocrine SystemEndocrine System

Endocrine System Regulation of the human body through chemical messengers called hormones to maintain homeostasis Homeostasis = stable internal environment

Endocrine Regulation Stimulus is detected Impulse sent to brain (hypothalamus) Hypothalamus to pituitary Pituitary sends message to gland Gland releases a hormone Hormone does work New stimulus is detected

Do Now Brain Pop video: Hormones Hormones

Hormones Chemicals released into the blood stream from a gland Needed in very small amounts Contain receptor molecules Act on specific parts of the body –Ex: Insulin will “lock in” to blood cell receptors to lower blood sugar. Insulin cannot “lock in” to other body cells because the receptor sites don’t match.

ENDOCRINE GLANDS Pituitary = master gland (controlled by the hypothalamus in the brain)

Pituitary Gland TSH – thyroid stimulating hormone ACTH – stimulates adrenal glands FSH – stimulates the ovaries Oxytocin – labor contractions Calcitonin – Calcium metabolism Releases hormone messengers (do not “do work”)

ENDOCRINE GLANDS Thyroid Gland – in neck Releases Thyroxine which regulates metabolism Parathyroids – 4 tiny glands behind thyroid Releases Parahormone regulates Calcium in blood

Adrenal Gland – on top of kidneys Releases Adrenaline which allows the body to respond appropriately in times of emergency or stress “Fight or Flight”

Pancreas – glands located within the pancreas –Releases Insulin which regulates blood sugar levels Diabetes – caused by decreased amounts of insulin which leads to increase blood sugar  coma  death if not medicated

GONADS – sex glands Ovaries Releases Estrogen – 2 nd degree sex characteristics/ cycle Releases Progesterone – cycle and maintain pregnancy Testes Releases Testosterone – 2 nd degree male characteristics and production of sperm production of sperm

Do Now Using the diagram on the board, fill in the chart.

Feedback Mechanisms A cycle in which the output “feeds back” to modify or reinforce the action of the system 2 types: (a)Positive feedback Change in the environment – increases the response Change in the environment – increases the response Ex: uterine contractions during labor (a)Negative feedback most common Change in the environment  creates a response message  makes a change  stops the response message

Ex: regulate blood sugar Sensor detects Sensor detects high blood sugar high blood sugar Pancreas Negative secretes feedback insulin shuts off insulin production Blood sugar Blood sugar drops drops - Ex: increase exercise  increased muscle activity  increases HR and BP and resp. rate  O2 to muscles

Disease Disease = failure of homeostasis – the body fails to work as it should Causes of disease: 1)Pathogens – organisms (germs) that invade the body ex: virus, bacteria, fungi. And parasites (spread) – Lyme, cold 2)Uncontrolled cell division

Cancer mass of abnormal cells called tumor 3) Inherited ex: CF, Down’s 4) Poor nutrition 5) Toxins 6) Organ malfunction 7) High risk – skin/lung cancer

In class assignment Brain Pop video: Puberty Puberty Multiple choice worksheet/vocab