1. CH. 4 Cellular Processes
Biology

2. 4A- Cellular Energy 4.1 Energy Relationships
Explain why energy is required for me
Define autotroph and heterotroph
Describe how energy is stored in ATP molecules

3. Energy and Life? The primary need of all cells is energy.
Only cellular need that is not recyclable in the environment
Must be in constant supple

4. Autotrophs and Heterotrophs
Organisms that make their own food
Plants, Algae, etc.- capture light energy and produce their own food.
Also known as Producers
Organisms that depend on other organisms for their energy
Consumers
Humans, animals, fungi, bacteria

5. ATP: The Energy Currency in Cells
ADP
ATP molecule made up of Adenosine (adenine + simple sugar) and three phosphate groups
Key to how ATP stores energy is found in the bonds between the three phosphate groups; these are bound to each other by unstable, high energy covalent bonds
A phosphate group broken off from the original three phosphate attached groups.

6. ATP: The Energy Currency in Cells
ADP
ATP ADP + P + Energy
ADP + P + Energy  ATP

7. 4.2 Photosynthesis Objectives:
Write a simple equation for photosynthesis
Explain how light energy is captured for use in photosynthesis
Describe the light-dependent phase and the Calvin Cycle
List the final products of photosynthesis
Explain how the environment affects photosynthesis

8. Photosynthesis
The process of absorbing light and converting it into stored chemical energy
Primary photosynthetic organisms: green plants and algae

9. Chlorophyll and Light
Chlorophyll- a green pigment, a primary catalyst of photosynthesis
Pigments- Special light absorbing molecules
Chlorophyll a and Chlorophyll b- The two primary pigments of photosynthesis
Found in the grana of chloroplasts in photosynthetic eukaryotic cells
Chlorophyll a is more abundant and serves as primary catalyst for photosynthesis

10. The Process of Photosynthesis
Light Dependent Phase
Calvin Cycle
First phase, also called “Light Reactions”
Step One: Light energy absorbed by pigments and used to energize electrons in a chlorophyll a molecule.
Step Two: e- Transport Chain
Step Three: Photolysis- splitting of water molecule into H+ ions, electrons, and oxygen
Step Four: NADP+ picks up 2 e- and H+ ion to become NADPH
Light Independent Phase- takes place in stroma of the chloroplast
Step One: CO2 molecule diffuses from cytoplasm into stroma, binds to RuBP. Energy stored in ATP and NADPH is used to produce PGAL.
PGAL molecules are used to make glucose and also more RuBP

11. Calvin Cycle in a Nutshell
Calvin Cycle produces sugar using the atoms from CO2, energy from ATP, and the electrons and hydrogen ions provided by NADPH
See PG’s 82 and 83

12. 4.3 Cellular Respiration
Cellular Respiration: the breaking down of a food substance into usable cellular energy in the form of ATP.
Glucose is primary food source of cellular energy, however, lipids, monosaccharides, and even protein can used.

13. Aerobic and Anaerobic Aerobic Anaerobic Requiring Oxygen No Oxygen
C6H12O6 + 6O2  6H2O+ 6CO2 +ATP
No Oxygen

14. Glycolysis
Go to PG. 87
The breakdown of glucose into pyruvic acid, H+ ions, and electrons
Step One: two molecules of ATP supply activation energy. Using energy and 2 Phosphates from ATP, glucose is broken down into 2 molecules of PGAL
Step Two: Each molecule of PGAL releases electrons and hydrogen ions to an electron carrier molecule (NAD+). Each PGAL molecule also has a Phosphate attached to it.

15. Glycolysis CONT.
Step Three: Each phosphate group added in Step 1 and 2 is removed and added to a molecule of ADP, forming 4 ATP molecules. This reaction produces 2 Pyruvic Acid molecules

16. Krebs Cycle
Pyruvic Acid reacts with an enzyme that removes a carbon from pyruvic acid to produce acetyl coenzyme A (Acetyl CoA), CO2, Hydrogen ions, ATP, and electrons

17. Electron Transport Chain
Majority of ATP produced here.
Converts 3 molecules of ADP to ATP
In total, one molecule of glucose produces 32 ATP

18. Aerobic Respiration Energy Output
Converts 40% the energy contained in a glucose molecule into the for of ATP

19. Alcoholic Fermentation
In this, the pyruvic acid molecule is changed to a molecule of ethyl alcohol in a two step process:
Step One: Pyruvic acid gives off a carbon dioxide molecule, converting it into a 2 carbon-compound
Step Two: 2-carbon compound takes the hydrogen ions and electrons from the carrier molecule NADH to make ethyl alcohol. The use of the of the hydrogen and the electrons frees the carrier molecule to be used again in glycolysis

20. Lactic Acid Fermentation
Has only one step: Pyruvic acid take the hydrogen and electrons from the NADH produced during glycolysis, freeing the carrier molecule to be used again in glycolysis to produce ATP

21. Fermentation Energy Output
Fermentation supplies no ATP energy beyond that obtained from glycolysis. Cellular fermentation, therefore, produces a net gain of only 2 ATP molecules per glucose molecule.

22. 4B- Cellular Metabolism and Protein Synthesis
Objectives:
Describe the structure and function of the three kinds of RNA
Differentiate between introns and exons
List and describe the steps in translation

23. Protein Synthesis The Code of Life
Code of life: 4 bases (amino acids)-
Adenine
Thymine
Guanine
Cytosine
All the “words” or “instructions” in the DNA are three letters long (Codons)

24. Types of RNA
mRNA- contains the code for a polypeptide chain of amino acids and carries the code from the DNA in the nucleus to the ribosomes, in the cytoplasm, where the code is read.
tRNA- where amino acids are attached. tRNA molecules are about 80 nucleotides long and are formed in the nucleus. The chain of nucleotides forms several loops. On the edge of these loops are anticodons (complimentary base pairs for specific codons in the mRNA)
G - C
A - U
C - G

25. Types of RNA
rRNA- manufactured by the DNA of the nucleus. It combines with various proteins in the cytoplasm to form a ribosome.

26. Translation
The process of assembling the polypeptide from information coded in the mRNA

28. The Manufacture of Messenger RNA
Exons: sections of mRNA that are actually read as codons when making the protein.
Introns: sections of transcribed RNA that do not code for amino acids and therefore cannot be translated into proteins. These tend to be cut out of the sequence.

29. Anabolism and Catabolism
Anabolism: process that build molecules and store energy
Catabolism: processes that break down molecules and release energy

30. Three types of Cellular Digestion
Intracellular Digestion: Phagocytosis or pinocytosis, materials are then broken down by enzymes.
Extracellular Digestion: enzymes released by vesicles outside of cell to breakdown food substances. The products are then absorbed through the membrane of the cell.