8.2

8.2 Summary

• Sunlight = for of electromagnetic energy


• Electromagnetic spectrum can show the range of electromagnetic energy.(colors are due to the pigments)


• Paper chromatography helps to discover the pigment.


• Water splitting photosystem and the producing NADPH is involved in the light reactions.

1) Explain why a leaf appears green.
A leaf appears green because green light is not absorbed.
2) Describe what happens when a molecule of chlorophyll a absorbs light.
3) Besides oxygen, what two molecules are produced by the light reactions?
The two other molecules are ATP and NADH.
4) Where in the chloroplast do the light reactions take place?
They take place in the thylakoid.

8.1~8.2 Vocab List

8.1 Section Vocabulary
Chloroplast: the cellular organelle where photosynthesis takes place
Chlorophyll: A type of chemical compounds that chloroplasts contain, which give these organelles a green color. All green parts visible contain chlorosplats and can carry out photosynthesis
Stroma: A thick fluid of the inner meembranes of a chloroplast which has a inner and outer membrane, similiar to the mitochondria's matrix.
Thylakoids: Suspended in the stroma are many disk-shaped sacs. They each have a membrane surrounding an interiro space, arranged in stacks called grana.
Light reactions: Convert the erngy in sunlight to chemical energy
Calvin Cycle: makes sugar from the atoms in carbon dioxide plus the hydrogen ions and high energy electrons carried by NADPH. the enzymes for the Calvin cycle are located outside rge rgtkakoids and dissolved in the stroma.
8.2 Section Vocabulary
Wavelength: the distance between two adjacent wave
Electromagnetic spectrum: The range of types of electromagnetic energy, from the very short wavelengths of gamma rays to the ver lkong wavelenths of radio waves
Pigments: a substance's color is due to chemical compounds
Paper chromatography: a laboratory technique which allows people to obersce rge dufferent pigments in a green leaf
Photosystems: within the thylakoid membrane, chlorphyll and other molecules are arranged in clusters, each containing a few hundred pigments molecules including chlorphyll.

8.1

Summary

• Photosynthesis takes place in chloroplast which have chemicals that give organelles green color.
• Chloroplasts has an inner, outer membrane, granum, stroma, thylakoid space, and thylakoid.
• Inside the inner membrane contains thick fluid. This fluid is called stroma.
• Photosynthesis's equation is 6 CO2 + 6H2O -> C6H1206 + 6 O2
• Photosynthesis is divided into two stages. One being light reaction and two being the calvin cycle. Light reaction changes sunlight into chemical energy. Calvin cycle uses carbon dioxide and hydrogen ions to make sugar.
  Concept Check 8.1

1. Draw and label a simple diagram of a chloroplast that includes the following structure: outer and inner membrane, stroma thylakoids



2.What are the reactants for photosynthesis? What are the products?
Reactants are carbon dioxide and water and the products are glucose and oxygen.


3.Name the two main stages of photosynthesis. How are the two stages related?
Light reactions and Calvin cycle are the two main stages of photosynthesis. They are related because they are both used in the photosynthesis and they both change different chemical reactions into different compound.

Chapter 5 Review

1.Whih of the following is not an organic moleule?
Water

2.Which of the following terms includes all the other terms on this list?
Carbohydrate

3.Which term is most appropriate to describe a moleculte that dissolves eaily in water?Hydrophilic

4.Cholesterol is an example of what kind of moleculte?
Lipid

5.The 20 amino acids vary only in their
aminogroups

6.A specific reactant an enzyme ats upon is called the
substrate

7.An enzyme does whih of the following
Lowers the ativation energy of a reaction

8.Besides satisfying your hunger, why else might you consume a big bowl of pasta the night before a race?
You would onsume the pasta since the carbohydrages help you get energy for the race.

9.How are glucose, sucrose, and starch related?
They are all carbohydrates.

10. What are steroids? Describe two functions they have in cells.
Steroids are lipids that have a ring shaped carbon skeleton. They also help your body by sending signals and this also choses weather you are a men or a women.

11.How are Polypeptides related to proteins?
Polypeptides make up proteins.

12.How does denaturation affect the ability of a protein to function?
Denaturation affects proteins because it causes the protein to unravel and lose its function and abilities.

14. Analyzing Diagrams.
a. One product of this reaction is represented by a question mark. Which molecule is it?
The molecule that is also produced is a water molecule.
b.What is this kind of reaction called? Explain.
Dehydration reaction, because when the two amino acids combine they need to bond so they give away a water molecule together which dehydrating.
c.If an amino acid were added to this chain, at what two places could it attach?
The possible places would be defintely consisting of a Hydrogen + Oxygen atoms or just a Hydrogen atom.
15.Analyzing Graphs
a.At which temperature does enzyme A perform best? Enzyme B?
Enzyme A performs the best when the temperature is at 35 Celcius and Enzyme B works best at 75 degree celsius
b. Knowing that one of these enzymes is found in humans and the other in thermophilic bacteria, hypothesize which enzyme came from which organism.
Enzyme A is from humans, and Enzyme B is from the weird bacteria.

5.5

Enzymes are proteins that speed up specific reactions in cells.



Enzymes and Activation Energy

-To start a chemical reaction, first need to weaken the chemical bonds

-molecules to absorb energy.

activation energy- start up energy



one way - heat up the mixture of molecule *then activation energy is produced*

Hot molecule colide with cooler molecule weakens the bond.



cellular reactions depend on the assistance of catalysts

catalysts-compounds that speed up chemical reactions.



enzymes-the main catalysts of chemical reaction in organisms are specialized proteins

enzymes provied a way for reactions to occur at the cell's normal temp.

enzyme do not supply activation energy to the reacting molecule, but lowers the energy requirement barrier so that the reaction can proceed at normal cell temp.



How Enzyme Work

A substrate binds to an enzyme at an active site. The enzyme-substance interaction lowers the activation energy required for the reaction to proceed. In this example, water is added to the weakened bond in sucrose, breaking sucrose into glucose and fructose.
CONCEPT CHECK:
1. Explain the role of activation energy in a reaction. How does an enzyme affect activation energy?
Activation energy in a reaction starts up the required molecules to get energy which is to trigger a chemical reaction and activate the reactants which allows a chemical reaction to happen. An enzyme affects activation energy because it helps to speed up cellular reactions and provides a way for reactions to occur at cell's normal temperature.
2. Describe how a substrate interacts with an enzyme.
A substrate interacts with an enzyme by helping this specific reactant fit into a particular region, the active site. When it fits in the active site, the active site changed slightly, fitting the substrate better.

5.4

amino acid-monomer consists of a central carbon atom bonded to four partners(carbon atom, remember forms four covalent bonds)

polypeptide-cells creat proteins by linking amino acids together into a chain which is called polypeptide.

denaturation-process of preotein.

Protein shape. influenced by the surrounding envrionment, usually aqueous.

water attracts hydrophilic side groups and reject hydrophobic ones-Hydrophilic amino acid tend to orient towards the outside edges of the protein and hydrophobic amino acids cluster in the center of the protein.

1) Give at least two examples of proteins you can "see" in the world around you. What are their functions?

Two proteins you can see in the world around you, are ones that form structures such as hair or fur, and make up the muscles of an organism.
2) Relate amino acids, polypeptides, and proteins.

Proteins are polymers constructed from amino acids, which are monomers with a central carbon atom, that are linked together into a chain called a polypeptides. Most polypeptide chains are around 100 amino acids in length.
3) Explain how heat can destroy a protein.

Heating it will destroy a protein because of the process called denaturation where protein unravels trying to work properly. As it goes by it will lose its shape and start losing attraction.
4) Which parts of an amino acid's structure are the same in all amino acids?Which part is unique?

Amino acids have three partner bonds to the centra carbon atom in all of them. They are hydrogen atom, carboxyl group, and an amino group. The difference is the fourth partner and which determines each protein's properties.

5.3

Lipids are compounds that avoid water. "Lipids surround and contain the watery contents of our cells, circulate in our bodies and send chemical signals to cells, and store energy in our bodies."(copyright.JunTakaki)
Fat - made up of carbon, backbone, glycerol.
Saturated fat-all three fatty acid chains have the maximum number of hydrogen atoms
Unsaturated Fat-has one or more fatty acid chains with molecules that don't bond with the maximum number of hydrogen atoms.
when lipids deposit, it may reduce the blood flow and cause a heart disease. One type of lipid is Steroids.
Steriods- molecules formed from carbon skeletons which make four fused rings. Has very different structure and funcition from fats. (eg.Cholesterol)
Concept Check
1.What property do lipids share?
The property that lipids share being hydrophobic.
2.What are the parts of a fat molecule?
The parts of a fat molecule are the glycerol three-carbon backbone.
3.Describe two ways that steroids differ from fat.
1)steroids differ from fats in the way they are structuredwhere one is four and one is three.
2)steroids differ from fats in the way that steroids are used as chemical signal in our body and fat doesn't.
4.What does the term unsaturated fat on a food label mean?
Unsaturated fat is probably more unhealthy than the saturated fat.