Chapter 8: Cellular Respiration, Photosynthesis and an Introduction to GMOs

What is the source of CO2 in the leaf disk experiment

Sodium Bicarbonate

Why did some leaf disk float at the end of the experiment?

They performed photosynthesis and produced O2

During cellular respiration is the gas used as a reactant by the reactions and is the gas released as a product of the reactions

oxygen, carbon dioxide

In what organelle does most of aerobic cellular respiration take place?

Mitochondria

In what organelle does photosynthesis take place?

Chloroplast

The dependent variable in the spinach disk experiment was the rate of photosynthesis which you measured by

counting how many disks floated over time (independent)

Why would phenol red change from yellow to orange/red in the presence of elodea in light?

Because the elodea used the CO2 for photosynthesis

Cellular Respiration equation

C 6 H12 O6 + 6 O2 —> 6 CO2 + 6 H2O+ ENERGY (ATP) ex: humans

Reactants

1. 6H12O6

2. O2

Products

1. CO2

2. H2O

independent variable

intensity of exercise

dependent variable

amount of CO2 produced

Photosynthesis balanced equation

6 CO2 + 6H2O + Light energy —→ C6 H12 O6 + 6 O2

Reactants (what goes in)

CO2

H20

Light energy

Products (what comes out)

C6H12O6

O2

Photoautotroph

organisms that produce their own organic molecules using light energy

Acid

pH below 7

yellow

Neutral

pH is 7

red

Basic

pH above 7

pink

Describe how the color of the phenol red changed in response to pH changes and changes CO2 levels?

• In acidic conditions ( High CO2 levels) turns yellow  (opposite)

• In neutral conditions ( Normal CO2 levels) stays red  

• In basic conditions ( Low CO2 levels) turns pink  (opposite)