Getting Energy and Matter into Biological Systems

1
Getting Energy and Matter into Biological Systems

Write a statement that explains what is taking
place in this picture
2
Review

• We, living organisms, need ________ in order to
  survive.
• Molecules like _________, ________, and _________
  found in food provide us this.
• Molecules are made of ____________ such as
  Carbon, Hydrogen, Oxygen, etc.
• These ___________ are what make up matter.
• So how do we get matter found in food in the
  first place? Who/what gets the credit?

3

• Photosynthesis!The process by which plants, some
  protists, and some bacteria use energy
  transferred from the sun to...
• synthesize LARGE, energy rich molecules from
  small ones. What do plants make?
• ? CO2 ?

4
Things that may affect the rate of photosynthesis

• Intensity of light
• Amount of CO2
• Water availability?
• What else?
• Color of light?
• Toxins?
• Soil nutrients?

5
A Plant Cell
6
Where does PS happen?

• All plants are made up of plant cells
• Most plant cells contain chloroplasts, which make
  them appear green
• Inside chloroplasts, there are structures called
  thylakoids
• In the thylakoid membranes, chlorophyll is stored
• Chlorophyll is a pigment that absorbs the suns
  energy

7
(No Transcript)
8

• Light energy from the sun hits the chlorophyll
  molecules
• Much of the light energy is absorbed but one
  wavelength of light is reflected off, not
  absorbed.
• This is the color of light that you see.

9
(No Transcript)
10
3 major events, but 2 phases

• Absorption of light energy
• 2. Conversion of light energy into chemical
  energy ? 1st PHASE
• outcome
• 3. Storage of chemical energy in the form of
  carbs a.k.a. glucose? 2nd PHASE
• outcome

11
How do you fix Carbon?
Bottom of a leaf
Cross-section of a leaf
12
(No Transcript)
13
Carbon Fixation is the process that converts
atmospheric Carbon Dioxide into carbohydrate
molecules (glucose, etc.)
14
Why does photosynthesis happen?

• Autotrophs use PS to get and store energy (as
  ___________)
• Heterotrophs eat autotrophs and use these
  carbohydrates as energy sources

15
The Big Picture
16
Reactions

• Photosynthesis
• Cell Respiration

17
Connect PS and CR reactions to Endo and
Exothermic reactions
18
Video Clip
http//www.teachersdomain.org/9-12/sci/life/cell/p
hotosynth/index.html
19
Homework due Wednesday

• Read Essay in textbook, Getting Light Energy into
  Biological Systems, p.367
• Complete the first half of Photosynthesis Review
  WS