Body Systems that Regulate Body Functions

Nervous System

What is the function of the nervous system?

Overview of a vertebrate nervous system

Structure of a vertebrate neuron

What are the functions of: dendrites, axons, synapses?

The main parts of the human brain

Heart rate & Breathing

Balance, Movement

Thinking, memory, learning

Homeostasis

“Master Gland”

REVIEW

Create a flow map to explain the series of events that happen from when you hear a loud noise to when you turn your head.

Receptors in ear receive sound information

Hormones & The Endocrine System

What is the function of the endocrine system?

Definitions

• Hormones– Chemical messages – Regulate activity of other cells– Help maintain homeostasis

• Endocrine glands– Secrete hormones

Endocrine System

Types of Hormones

• Protein hormones– Polar– Can they go through the cell membrane?

• Steroid hormones– Made from cholesterol– Can they go through the cell membrane?

Hormones are Chemical Signals

How does a protein hormone regulate a cell?How does a steroid hormone regulate a cell?

Selected Hormones & Glands

How can hormones maintain homeostasis?

NegativeFeedback

Adrenal Glands & Stress

• “Fight or Flight” – Immediate Stress– Epinephrine & Norepinephrine – hormones– Prepare body for emergency action

• Increase heart rate• Increase blood glucose level

• Long-term Stress– Cortisol & Aldosterone – hormones– Makes more energy available to body– Suppresses immune system– Increases blood pressure

Time for a yoga class?

ReviewCreate a Thinking Map of your choice to summarize what hormones do and how they work.

Immune System

What is the function of the immune system?

First Line of Defense

• Blocking germs from getting in in the first place

– Skin– Mucous membranes– Low pH in stomach

Second Line of Defense

• Attacks invaders when they get in

• Not specific – kills all cells that aren’t supposed to be there

Phagocytotic WBC InflammationFever

Third Line of Defense

• Specific – attacks a specific invader (antigen)– Examples – cold, flu, measels

• Made up of white blood cells– Cytotoxic T cells– B cells– Helper T cells

• Antigens – cause a specific immune response

Helper T-Cells1. A macrophage (phagocytotic WBC) eats an invader2. It wears surface proteins of the bacteria 3. The Helper T-Cell that can fight this infection recognizes the surface protein4. The Helper T-Cell organizes B Cells and Cytotoxic T-Cells

** Helper T-Cells are Coordinators **

Cytotoxic T-Cells

Kill infected cells by causing them to lyse (pop open)

B CellsMake antibodies; Antibodies prevent invader from infecting new cells

Lock and key fit

(Invader)

Memory & ImmunityAntibodies and Memory Cells “remember” an infection so you only get sick once.

HIV attacks Helper T-Cells

Very low Helper T CellCan’t fight infections

• Cause immunity without sickness

• Cause specific immune response; build up of antibodies

• Examples– Killed microbes– Parts of microbes– Weakened microbes

Vaccines

Review

Think of an analogy to compare and contrast the non-specific and specific immune responses.

Create a Thinking Map to summarize the function of the Immune System.