Energy & Photosynthesis - Part 1

Question 1

All living things must be able to:

Answer 1

1. Produce energy from the environment
2. Store energy for future use
3. Use energy in a controlled manner

Produce energy&raquo_space; Store energy&raquo_space; Use energy

Question 2

Autotrophs

Answer 2

can make their own food

Question 3

Heterotrophs

Answer 3

must ingest food from other sources

Question 4

2 Universal Laws regarding Energy

Answer 4

1. Energy can be converted from one form to another, but it CANNOT be destroyed
2. Energy cannot be converted without the loss of usable energy

Question 5

Metabolism

Answer 5

all of the chemical reactions in a cell made up of: anabolism & catabolism

Question 6

Anabolism

Answer 6

uses energy to build larger molecules from smaller molecules (small to > LARGE) = photosynthesis

Question 7

Catabolism

Answer 7

releases energy by breaking down larger molecules into smaller molecules (LARGE > to > small) = respiration

Question 8

Adenosine Triphosophate = ATP

Answer 8

• Nucleotide with 3 phosphate groups (large amounts stored in the bonds between hose phosphate groups
• Breaking bonds = releases energy to be used by the cell

Question 9

How does ATP work?

Answer 9

• When the bonds are broken, each phosphate that comes off releases energy

Question 10

Photosynthesis can be divided into 2 parts

Answer 10

• The Light Reaction

* The Dark Reaction

Question 11

Light Reaction occurs here

Answer 11

in the chloroplasts - specifically in the thykaloid (flattened membranes in stacks called grana) (pancakes)

Question 12

Light is absorbed here

Answer 12

In the chloroplasts via the pigments

Most important is the chlorophyll

Question 13

Dark Reaction occurs here

Answer 13

In the STROMA of the choloroplasts (the fluid-filled space outside the grana)

Question 14

Name the reactants in the formula for photosynthesis

Answer 14

6CO2 + 6H2O —-> (sun energy) —->

C6H12O6 + 6O2

Question 15

Light Reactions

Answer 15

Light Reactions absorb energy from the sun and convert it into a chemical bond of ATP and NADH
+AKA: Light-DEPENDENT Reaction (DEPENDS on light)

Question 16

Dark Reactions

Answer 16

Dark Reactions take ATP and use it to make sugar

+AKA: Light-Independent Reaction

Question 17

The Light Reaction

Step 1 - Light Absorption

Answer 17

Step 1. Light Absorption

• Photons hit chlorophyll inside membranes of thlakoid
• Photons cause chlorophyll molecules to become excited
• Electrons in chlorophyll become excited and jump to higher energy level

Question 18

The Light Reaction

Step 2 - Electron Transport

Answer 18

Step 2 - Electron Transport

• Excited electron is “picked up” from PS II by an electron carrier in thylakoid membrane
• Electron is shuttled among a series of electron carriers to get to PS I where it is re-energized by more photons (light)
• Electron is picked up by a ferrodoxin (protein)
• Ferrodoxin transfers electron to NADP (electron carrier), to make NADPH, an energy storage molecule

Question 19

The Light Reaction

Step 3 - Oxygen Production

Answer 19

Step 3 - Oxygen Production
* Light energy causes water molecule to split
~ Electron released to replace excited electron from PS II
~ H+ moves into thylakoid space
~ Oxygen (O2) released as a waste product

Question 20

The Light Reaction

Step 4 - ATP Production

Answer 20

Step 4 - ATP Production

• so many H+s create a concentration gradient
• H+s flow from high concentration inside to low concentration outside through a special-enzyme - ATP Synthase
• ATP is made

Question 21

See also Photosynthesis Part 2: Calvin Cycle and Respiration.

Answer 21

It’s the next set of cards in the Bio library.