1. SCIENCE GATEWAY Biological Systems and Life Processes
REVIEW AND PRACTICE
BIOLOGY

2. What does it mean to be alive?
Life
What does it mean to be alive?

3. Biological Systems
Homeostasis

4. ENERGY/MATTER TRANSFORMATIONS
RESPIRATION AND PHOTOSYNTHESIS

5. RESPIRATION
Process by which plants and animals obtain energy from foods
Organisms break down food into smaller molecules, which combine with oxygen
Energy stored in sugars (glucose) is released as ATP

6. RESPIRATION Process occurs in two phases:
Glycolosis: breakdown of glucose into pyruvic acid
Occurs in cytoplasm in eukaryotes
Oxidation of pyruvic acid to carbon dioxide and water
Occurs in mitochondria

7. RESPIRATION
After the breakdown of glucose, waste products, such as CO2 and water, leave through cell membrane

8. RESPIRATION Chemical reactions produce the nucleotide, ATP
ATP stores energy
Energy is released from ATP when needed
ATP is used for all the energy-consuming activities of the cell

9. RESPIRATION

10. OVERALL REACTION Respiration
C6H12O O2 → 6CO H2O + energy
Glucose Oxygen Carbon Dioxide Water
Similar to combustion reaction (burning)

11. PHOTOSYNTHESIS 6CO2 + 6H2O + energy → C6H12O6 + 6O2
Uses CO2 and water
Releases oxygen as waste
Process of producing food in plants
Chloroplasts (cells) use energy from the sun to produce glucose

12. PHOTOSYNTHESIS Light Reaction
Chlorophyll traps the energy available in sunlight
ATP is produced
ATP stores energy for cell processes
Water is split into hydrogen and oxygen
Some oxygen is used in respiration
A great deal of oxygen is released to the environment

15. Dark Reaction
CO2 and other chemicals combine to form glucose, using energy from ATP
Some of the glucose produced is used in respiration
Some glucose is used for growth
Excess glucose is stored in roots, stems and leaves of plants

16. RELATIONSHIP BETWEEN PHOTOSYNTHESIS AND RESPIRATION
ALL plants and animals carry on respiration
Uses oxygen
Releases water and CO2
Photosynthesis
Plants with chlorophyll carry on photosynthesis
Produces oxygen
Uses water and CO2

17. LIFE FUNCTIONS

18. BASIC LIFE FUNCTIONS
All living organisms need to perform certain functions to remain alive
Living organisms contain systems designed to carry out these essential functions

19. BASIC LIFE FUNCTIONS Six basic functions: D Digestion R Respiration
R Reproduction
R Response
E Excretion
G Growth

20. BASIC LIFE FUNCTIONS
DIGESTION
The process of changing food into a usable form to provide energy

21. BASIC LIFE FUNCTIONS RESPIRATION The process of using food
Breaking down stored food and combining it with oxygen to provide energy
The exchange of gases to produce food and energy

22. BASIC LIFE FUNCTIONS
REPRODUCTION
The process by which new organisms (offspring) are produced

23. BASIC LIFE FUNCTIONS RESPONSE
How organisms react to changes in their surroundings

24. BASIC LIFE FUNCTIONS
EXCRETION
The process by which the body gets rid of liquid waste
The lungs, kidneys, and skin function to excrete waste produces created by the body

25. BASIC LIFE FUNCTIONS
GROWTH
The repair and production of new and larger cells within a living organism

26. TO BE LIVING
An organism must perform all life functions to be considered living
However, these life functions may be carried out in different ways

27. BACTERIA Prokaryotic organisms
Single-celled organisms that lack a nucleus
Identified by shape, type of cell wall, movement, and the ways in which they obtain energy
Most reproduce by binary fission, creating two identical cells
May participate in conjugation
Genes move from one cell to another

28. ARE VIRUSES ALIVE? Not considered alive by many biologists
Not composed of cells
Not able to reproduce independently; must use host cell
Infect living cells
Can make copies of themselves
Made of a DNA or RNA core surrounded by protein coat
HIV Virus

29. That’s a lot of knowledge! Think you can remember?
WWHHHEEE!!!!
That’s a lot of knowledge! Think you can remember?
GATEWAY – HERE I COME!

30. ARE YOU READY???!!!!
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