Y3-TV3-LSN1

Getting organised:

• Join the Google Classroom.
• Join the Lessonup group.
• Join the WRTS group.
• Download PDF of the textbook.
• Does everyone have a notebook?
• Join this presentation. 

Good way to make notes: Cornell method

Homeostasis, Health & Disease

Introduction

Learning Goals:

• I know what biology is.
• I know the hierarchy of biological organization
• I know the different organ systems and their function
• I know what homeostasis is
• I know how the body can keep homeostasis

What do you think biology is about?

Biology: the study of living organisms. 

Key words:

• biology
• molecule
• organel
• cell
• tissue
• organ
• organ system 

• organism
• population
• ecosystem
• bioma
• biosphere
• integumentary
• homeostasis

• homeostasis
• negative feedback
• positive feedback
• sensor
• controlor
• effector

The hierarchy of biological

 organization

molecule

cell

organel

organ

organsystem

tissue

population

organism

ecosystem

Bioma

The hierarchy of biological organization

name all organ systems you know

Organ systems

Assignment:

Write down all the body systems in your note book and think about the function of each body system.

reproductive system

urinary system

respiratory system

digestive system

lymphatic system

endocrine system

ciculatory system

nervous system

muscular system

skeletal system

integumentary system

facilitates gas exchange between cells and the environment

Breaks down food into usable nutrients

Responsible for transport through the body

Extracts and excretes dissolved waste product from the blood

secretes chemical signals that allow body systems to respond to environmental changes and to one another

allows us to perceive and respond to the world around us

gives the body structure 

 largest organ of the body that forms a physical barrier between the external environment and the internal environment that it serves to protect and maintain.

responsible for absorbing fat from the digestive system, maintaining fluid balance, and supporting the cells of the immune system

facilitates the production of offspring

Allows the body to move

Body systems and their functions

• Integumentary system - The largest organ of the body that forms a physical barrier between the external environment and the internal environment that it serves to protect and maintain.
• Muscular system - Allows the body to move
• Reproductive system - facilitates the production of offspring
• Endocrine system - secretes chemical signals that allow body systems to respond to environmental changes and to one another
• Urinary system - Extracts and excretes dissolved waste product from the blood
• Digestive system - Breaks down food into usable nutrients
• Lymphatic system - responsible for absorbing fat from the digestive system, maintaining fluid balance, and supporting the cells of the immune system
• Respiratory system - facilitates gas exchange between cells and the environment
• Nervous system - allows us to perceive and respond to the world around us
• Skeletal system - gives the body structure 
• Circulatory system - Responsible for transport through the body

Together the organ systems, with a big role for the endocrine and nervous system, help to keep the body in homeostasis........Homeo what?

Homeostasis - the tendency to resist change in order to maintain a stable, relatively constant internal environment.

e.g. body temperature, blood pressure, pH, etc.

High

Low

Low

High

too high

too low

Hypothalamus

Assignment:

Write down a summary of this lesson which briefly capitulates what you have learned today.

Biology has a hierarchical organization. The organization level of organ systems is distinguished in 11 level which together keep the body in homeostasis.

Homeostasis - keeping conditions inside the body in balance

                     done by the endocrine system and the nervous system

Negative feedback - causing the opposite reaction: 

                              temperature high      temperature low  

                              temperature low        temperature high

Positive feedback -  causing the reaction to get even stronger

Examples of conditions which are under control: 

                             Blood sugar

                             Water level

                             pH

                             carbondioxide 

                             temperature

Summary

Assignment:

Try to make a feedback loop for bloodsugar regulation by filling in the correct words in this scheme.

Copy the scheme in your notebook and use "high blood sugar" as stimulus

Tip: read page 96 until 98 in your kerboodle