Endocrine System

Endocrine System

Homeostasis

Multiple Choice

Which sense organ detects light and colour?

• Ear

• Skin

• Eye

• Nose

Multiple Choice

Which type of neurone takes an impulse from the CNS to a muscle or gland?

• Sensory

• Relay

• Motor

Multiple Choice

What is the gap called between neurones?

• Bridge

• Cleft

• Neurotransmitter

• Synapse

Multiple Choice

How many neurones are involved in a reflex arc?

• 1

• 2

• 3

• 4

Multiple Select

What are the parts of the CNS?

• Brain

• Nerves

• Spinal Cord

• Receptors

Learning Objectives

• Defining a hormone

• Identify the organs of the endocrine system

• Describing what each hormone does

Endocrine System

The endocrine system is made up of glands that secrete chemicals called hormones directly into the bloodstream

A gland is an organ that secretes hormones

A hormone is a chemical that travels in the bloodstream to a target organ

Endocrine System

Some hormones act rapidly, like adrenaline, but this is still much slower than the nervous system

Other hormones act over many months or even years, such as testosterone, and the effects are long lasting

Open Ended

How many hormones can you name? Make a list of as many as you can think of before hitting enter!

There are several glands you need to know about

Open Ended

Think of a time you were REALLY scared? What changes happened in your body?

Adrenaline

Released from: Adrenal Gland

Adrenaline is called the 'flight or fight' hormone

It prepares the body for stressful situations:

Increases heart rate

Increases breathing rate

Diverts blood to muscles

Insulin

Released from: Pancreas

Lowers blood sugar

Acts on the liver and muscles

Anti-diuretic hormone (ADH)

Released from: Pituitary Gland (master gland)

Controls water content of the blood

Acts on the kidneys

Testosterone

Released from: Testes

Promotes growth of male characteristics eg. hair growth, sperm production

Oestrogen

Released from: Ovaries

Promotes growth of female characteristics, eg. egg production, breast development

Other Hormones

• Follicle Stimulating Hormone (FSH) - Pituitary gland

• Luteinising Hormone (LH) - Pituitary gland

• Progesterone - Ovaries

• Thyroxine - Thyroid gland

Multiple Choice

Which hormone is produced by the testes?

• Oestrogen

• Adrenaline

• Insulin

• Testosterone

Multiple Choice

Which hormone lowers blood sugar?

• Adrenaline

• Insulin

• ADH

• Ostrogen

Multiple Select

Select all of the glands

• Pancreas

• Ovaries

• Liver

• Stomach

• Pituitary

Multiple Choice

Which gland produces anti-diuretic hormone?

• Pituitary

• Adrenal

• Pancreas

• Testes

Multiple Choice

Which hormone is responsible for female characteristics?

• Testosterone

• Adrenaline

• Thyroxine

• Oestrogen

Multiple Choice

Which gland is known as the 'master gland'?

• Adrenal

• Pancreas

• Pituitary

• Thyroid

Multiple Choice

How do hormones get to their target organs?

• Along nerves

• In urine

• In blood

• Through the skin

Negative Feedback

Homeostasis is the control of a constant internal environment in the body

Hormones have a major role in this control and most work through negative feedback loops

Negative feedback systems work by bringing levels down when they get too high, or raising them up when they get too low

Thyroxine

The thyroid gland in your neck uses iodine in your diet to produce thyroxine

Thyroxine is important for controlling metabolic rate – how fast substances can be broken down or built up

The release of thyroxine is controlled by Thyroid Stimulating Hormone (TSH) released from the pituitary gland

Positive Feedback - Adrenaline

If you are stressed, angry, excited or frightened your body needs to be ready for action

•Heart and breathing rate increase

•Glycogen is converted to glucose for respiration

•Pupils dilate to let in more light

•Mental awareness increases

•Blood is diverted from the digestive system to muscles in limbs

If negative feedback stopped these responses then your body would not be prepared for the ‘flight or fight’ response

When the threat has gone the adrenal gland stops producing adrenaline

Multiple Choice

Thyroxine level is detected by the:

• Adrenal gland

• Pancreas

• Pituitary gland

• Ovaries

Multiple Choice

What does the pituitary gland do if it detects a rise in thyroxine levels?

• Stops TSH production

• Releases TSH

• Stops producing thyroxine

• Releases thyroxine

Multiple Choice

What effect does increased TSH have on the thyroid gland?

• Stops producing thyroxine

• Stops producing adrenaline

• Produces thyroxine

• Produces testosterone

Hormones

• Hormones are chemical messengers

• They are generally slow to act and long lasting

• They travel in the bloodstream to their target organ

• They coordinate and control the body

Nerve Impulses

• Nervous signals are electrical impulses

• They are fast to act and short lived

• They travel along nerve cells (neurones)

• They coordinate and control the body

Multiple Select

Select all the statements that relate to hormones

• Fast transmission

• Long lasting

• Travel in bloodstream

• Short lived

• Chemical

Multiple Select

Select all the statements that relate to nervous impulses

• Electrical

• Chemical

• Travel in neurones

• Fast acting

• Slow transmission

Multiple Choice

What hormone would be released if you ate a chocolate bar?

• Adrenaline

• ADH

• Testosterone

• Insulin

Multiple Choice

What hormone would be released if you were chased by a dog?

• ADH

• Insulin

• Oestrogen

• Adrenaline

Poll

How do we feel about this topic?

• I understand!

• I'm going to write a glossary of key words

• I have no idea what a hormone is!