CHEMICAL REGULATION

Regulation - Control of all activities in an organism.

This helps maintain balance (Homeostasis). 2 body systems work to maintain this-Nervous and Endocrine(hormones)

7. Regulation

REGULATION involves the control and coordination of life activities.

Both chemical and nerve

control aid in the

maintenance of homeostasis in

living organisms.

In multicellular animals, there is nerve control in addition to chemical control.

Life activities are controlled by chemicals called HORMONES.

(This happens in Plants and Animals.)

Plant hormones called AUXINS are produced. Auxin helps plants grow.

Dancing Plants

When auxin is released in un-even amounts the plant will bend.

The growth of a plant toward a light source is called a PHOTOTROPISM.

Specialized leaves called tendrils grasp

and wrap around objects.

Tendrils

In animals, growth, reproduction and metabolism are controlled by hormones.

Butterfly Video

See parasitic wasps laying eggs in aphids.

And what happens when similar parasites mess with a caterpillars normal growth hormone signals.

2 Types of Glands in Humans

EXOCRINE GLANDS secrete substances locally.

They use Ducts to carry the materials directly to the place where they are used.

The ENDOCRINE GLANDS secrete hormones directly into the blood. There are no ducts.

The hormones are transported throughout the

body by the circulatory system.

The organs affected by hormones are called the

TARGET ORGANS.Brain POP !

Many hormones are secreted by the pituitary gland.

The pituitary is called the MASTER GLAND because of

its effect on the other glands.

One of the many pituitary hormones is called GROWTH HORMONE (HGH).

Growth hormone regulates the physical growth of the body.

When too much growth hormone is released, a person grows too much.

MMA Fighter - Hong Man Choi(7 ft 2 in) and weighs 166.6 kg (367 lb)

When too little growth hormone is released, a person

grows too little.

It is rare for individuals affected by primordial dwarfism to live past

the age of 30.

See video of Kenadie

The THYROID gland secretes THYROXINE which regulates metabolism.

The ADRENAL GLANDS produce ADRENALINE.

Adrenaline increases a person’s heart rate and

breathing rate in emergency situations.

This produces the “fight or flight”

response.

It also produces an athletic “high” when you exercise or participate in sports.

The PANCREAS has both endocrine and exocrine functions.

It produces both digestive enzymes and

hormones.

REMEMBER THIS??Bile is made in the liver.

It emulsifies fats.

The PANCREAS produces two

important hormonesINSULIN and GLUCAGON.

Together, these hormones maintain a person’s blood sugar

concentration.

When the pancreas cannot produce enough

insulin, a person has DIABETES.

Diabetics need regular injections of insulin to

help maintain their blood sugar at a constant level.

If not properly managed, diabetes can lead to heart

disease, blindness, nerve and kidney damage.

The OVARIES and TESTES are referred to as the

human GONADS.

They produce specialized reproductive cells and

hormones.

ESTROGEN stimulates the development of female reproductive

organs and secondary sex characteristics.

It also stimulates egg production and the

menstrual cycle.

TESTOSTERONE stimulates the

development of male reproductive organs and

secondary sex characteristics.

It also stimulates sperm production.

If Ya Smellllllll

What the……..

People use synthetic testosterone to increase the size of their bodies and their athletic

performance.

There are many negative side effects of steroid use.

•shrinking testes•stunted growth•acne and skin rashes•rage•baldness•heart disease

The endocrine system uses NEGATIVE FEEDBACK to regulate the body.

Negative feedback works to maintain homeostasis.

Remember STEROID GUY??

What was some of the NEGATIVE

FEEDBACK that affected his

body??