2. LIFE CHEMISTRY: CHON
Carbon C
Hydrogen H
Oxygen O
Nitrogen N
Cells put these atoms together to make useful
molecules for food and energy.
3. 4 Macromolecules for LIFE:
1. Carbohydrates: (sugars)
2. Lipids: (fats & oils)
3. Proteins: (amino acids)
4. Nucleic acids: (DNA & RNA)
Glucose is a
carbohydrate
VIDEO: Macromolecules- a beginner guide
4. C A R B O H Y D R A T E S
• Sugars, starches,
cellulose
• Have ‘ose’ on the end of
the word
• Made by plants through
photosynthesis.
OTHER WORDS FOR SUGAR:
Glucose (grape sugar, corn
sugar, dextrose)
Fructose (honey)
Galactose (part of milk…
lactose)
Monomer:
(small organic blocks)
CH2
Polymer:
(large organic blocks)
C H O
6 12 6
6. HOW DO PLANTS GET WATER?
• Small, simple plants like mosses and liverworts
absorb water through simple diffusion; they
must live in wet spaces
7. • More advanced plants use
roots to absorb water and a
vascular system to pull the
water up to other parts of
the plant
• Therefore, these plants can
get taller
Xylem: path that water &
minerals take up the plant
Phloem: path that glucose
from leaves take down the
plant
8. •Transpiration-
process by which
plants lose water
through the leaves
99% water taken
into roots are
transpired out the
leaves
2. Water through
cortex of root to
xylem & up stem
1. Water from soil
into root hairs
3. Transpiration in
leaves helps draw
water up stem
4. Water moves
up stem to veins
to cells
As water
transpires out
of the stomata,
capillary action
pulls up the
next molecule…
water moves
up the tree
9. ENERGY
MOVEMENT
VOCABULARY
simple diffusion photosynthesis caretonoids
transpiration reactant enzyme
phloem product
xylem carbohydrate
light energy starch
chemical energy stroma
thermal energy thylakoid
glucose grana
chlorophyll light reaction
stomata dark reaction
11. PHOTOSYNTHESIS
• process by which autotrophs convert the sun’s
energy into glucose
• Occurs in the chloroplasts of plant and some
protist cells
• Glucose C6H12O6
BREAK IT DOWN
Photo- light
Synthesis- making
21. 1. Chlorophyll- main
pigment type
Absorbs blue and red
wavelengths
2. Carotenoids-
secondary pigment
types
Absorbs violet to green
wavelengths
Pigment: a substance that absorbs light and
produces color
22. Leaf stoma- opening in the leaf that allows the
exchange of gases.
CO2 enters
O2 and H2O exits
23.
24. • When the plant has adequate water, the
stoma remain open
• When the plant needs water, the stoma close
to prevent water loss… temporary condition
25. Since both H2O and CO2 are required for
photosynthesis, it’s important that the plant stays
hydrated.
26. During this first (light) part of
photosynthesis, light hits the
chlorophyll and “knocks” apart
the water molecule into Oxygen
and Hydrogen
Given off as oxygen
gas by plants
Goes to ATP
molecule
27. “Dark reactions”
During the second part of photosynthesis, the
trapped energy is used to make glucose from
carbon dioxide.
*NOTE: These reactions can
occur in the light or dark*
VIDEO: Nature’s Smallest factory: The Calvin Cycle (5:30)
28. • Some plants make and store a lot of sugar: starch
• We eat these plants
• We also isolate the sugar to sweeten things
29. At the end of the photosynthesis process,
glucose and oxygen are released.
VIDEO: Amoeba Sisters- Photosynthesis and the Teeny Tiny Pigment Cakes
30. 1. Chlorophyll absorbs light
from the sun
2. Sun’s energy splits water
molecule into hydrogen &
oxygen
3. Hydrogen joins
carbon dioxide to
make food
(sugar/glucose)
4. Sugar carried through the
plant; oxygen is released into
the air
6 6 6
H2O O2CO2 =+ + C6 H12 O6
PHOTOSYNTHESIS
MOVE
(Very over-simplified)
CC VIDEO: #8
Photosynthesis
(10 min)
31. How do you measure the rate of
photosynthesis?
• Rate of oxygen output
• Rate of carbon dioxide uptake
• Rate of carbohydrate production
Elodea photosynthesizing
32. Rate of Photosynthesis
• Depends on
• enzymes and how they work
• Light intensity
• CO2 concentration
• Temperature
• Amount of chlorophyll
VIDEO: Photosynthesis: Crash Course #8
33. Rate of Photosynthesis
Light intensity
• Increasing light intensity increases rate of
photosynthesis until another limiting factor
becomes in short supply. Then it will
plateau
34. Rate of Photosynthesis
CO2 concentration
• If concentration of CO2 increases, so will
photosynthesis, again until a limiting factor
causes this rate to
plateau
35. Rate of Photosynthesis
Temperature
• The chemical reactions are controlled by
enzymes (proteins that cause a reaction to
happen)
• Temperature can affect
the usefulness of an
enzyme: at high
temperatures, enzymes
are denatured
(become unusable)
36. Rate of Photosynthesis
Amount of chlorophyll
• Plants with poor lighting conditions are
darker b/c the plant produces more
chlorophyll to absorb required light
• Some plant diseases affect amount of
chlorophyll which affects photosynthesis
• Variegated varieties
require more light b/c
of lack of chlorophyll
pigment