Chapter 5 review

1. Which of the following is not an organic molecule? c. water
2. Which of the following terms includes all the other terms in this list? b. Carbohydrate
3. Which term is most appropriate to describe a molecule that dissolves easily in water?
d. organic
4. Cholesterol is an example of what kind of molecule? b. lipid
5. The 20 amino acids vary only in their b. side groups.
6. A specific reactant an enzyme acts upon is called the a. Catalyst
7. An enzyme does which of the following? b. lowers the activation energy of a reaction.
8. Besides satisfying your hunger, why else might you consume a big bowl of pasta the night before a race?
I might consume a big bowl of pasta for energy, proteins, minerals, etc for the night before the race.
9. How are glucose, sucrose, and starch related?
They are all polysaccharides.
10.What are steroids? Describe two functions they have in cells.
Steroids are lipid molecule in which the carbon skeleton forms four fused rings. The two functions are: 1. estrogen. 2. testosterone.
11.. How are polypeptides related to proteins?
polypeptides are the things that make proteins and polypeptides are made out of amino acids.
12. How does denaturation affect the ability of a protein to function?
It affects the protein by making it lose it's normal shape.

14. a. One product of the reaction is represented by a question mark. which molecule is it?
Water molecule.
b. Whit is this kind of reaction called? Explain
It is called a dehydration reaction. de means to remove and hydro means water. so it means the reaction that removes water.
c. If an amino acid were added to this chain, at what two places could it attach?
1. it could attach at the ____H part
____________________________-\
______________________________N
_____________________________/
___________________________H
2. it could ba also attached at the
___________________O
__________________// part.
_________________C
__________________\
__________________-OH

15. a. At which temperature does enzyme A perform best? Enzyme B?
At about 36 degrees is when enzyme A perform best. At about 76 degrees is when enzyme B perform best
b. knowing that one of these enzymes is found in humans and the other in thermophilic(heat-loving) bacteria, hypothesize which enzyme came from which organism.
Enzyme A should be found in humans and enzyme B should be found in thermophilic bacteria.
c. Propose a hypothesis that explains why the rate of the reaction catalyzed by enzyme A slows down at temperatures above 40 °C.
It lowers down because it has finished it's reaction and it starts to cool down.

5.1

Carbon is the main ingredient of organic molecules, Most carbo-based molecules are classified as organic molecules and non-carbon-based molecules are classified as inorganic molecules. Carbon can bond with atomes of other elements such as water, and molecules that are composed of only water and carbon are called hydrocarbons. Monomers are large molecules that are built from many similar molecular units, and polymers are long chains of monomers.

1. Draw a molecule that has a three-carbon skeleton and a hydroxyl group on the middle carbon.

(I stands for bonds)

______H_____H__-__H

____ ┃____ I_ I

H ----- C ------- C--------C -------- OH

_____I___ _I___ _I
______H___ _H___ _H

2. Explain the connection between monomers and polymers.

Monomers are smaller molecular units, and polymers are made of monomers.

3.What molecule is released during constuction of a polymer? What is this reaction called?

Each time a monomer is added to a chain, a water molecule would be released, and this is called a dehydration reaction.

4. Draw at least three ways in which five carbon atoms could be joined to make different carbon skeletons.

1. ___________H _____H____ H_____ H_____ H
_____________I______I______I_____ _I_____ I_
_______H ----- C -------- C--------C -------- C-------C-------OH
_____________I_______I_____I_______I_____I__
____________H______ H____ H______ H____ H

2.

_______CH2OH

_________

_________C-----------------------O

___H___ /_I_______________ \_____ H

____\__ /_ H _______________\ ____/

_____\ /____________________ \__ /

_____C_____________________ C

____/ __\ __OH _________ H ___/_ \

___/____ \__I____________I___ /___ \

_HO____ \_I___________ _I__ /____ OH

_________C---------------------C

_________I______________I_

________H_____________OH

3.

__-__H___ H__ O---- H--- H

--------I-------I----II-----I------I---

H-----C-----C--- C-----C----C----H

--------I------I------------I-----I--

-------H ----H ----------H ---H

5.5 abc

How an enzyme work.

Enzymes are proteins that speed up specific reactions in cells.

For a chemical reaction to occur, you need to provide it a "start-up" energy, and it is called activation energy. To make a chemical reaction occur easier, we have enzymes that can lower the activation energy and make it easier.

For making a enzyme work, eveery kind of enzyme is in a specific shape that can only fit the specific molecule, and when the reactants come in, it makes the reactants bind to it, then turn it into the products.

1. Explain the role of activation energy in a reaction. How does an enzyme affect activation energy?

The role of activation energy in a reaction is like a barrier between the reactants and the products, and an enzyme effects the activation energy by lowering the activation energy.

2. Describe how a substrate interacts with an enzyme.

A way that an enzyme lower activation energy is by accepting two reactants into the adjacent sites. and makes them react more easily.

1. Proteins are one of the main structure of most function of cells. 2. A protein is a polymer constructed from a set of just 20 kinds of monomers called amino acids.
3. They form structure of such as hair and fur, muscles, and provide long-term nutrient storage.
4. Proteins are created by cells and cells create proteins by linking amino acids together into a chain called a polypeptide.











Questions:


1. Give at least two examples of proteins you can "see" in the world around you. What are their functions?
Egg white(non-fried), hair. They make up muscles and provide nutrient storage.




2. Relate amino acids, polypeptides, and proteins.
Amino acids make up proteins and polypeptides but polypeptides are in a shape of a chain and proteins are not




3. Explain how heat can destroy a protein.
When heat get into a protein, it can make it lose it's normal shape, this process is called denaturation.




4. Which parts of an amino acid's structure are the same in all amino acid? Which part is unique?
All Amino acid monomers contains carbon.
It's unique part is the difference of the side group

5.3

steroid molecule

Lipids include fats and steroids, lipids are water-avoiding compounds. And fat consists of a three-carbon backbone called glycerol attached to three fatty acids. Lipid molecule in which the carbon skeleton forms four fused rings called steroids. Cholesterol is the best-known steroid. It is found in the membranes that surround your cells. it might block your blood vessels.

Structure of fat molecule

1. What property do lipids share?

They are all water avoiding compounds.
2. What are the parts of a fat molecule?

Basically, two parts. 1. Glycerol. 2. Three fatty acids.

3. Describe two ways that steroids differ from fats.

a. For steroids, the carbons form 4 rings but for a fat, instead of 4 rings, it forms glycerols attached to three fatty acids.

b. For fats, there are saturated fats and unsatuated fats. But for steroids, there are no saturated steroids and unsaturated steroids.

4. What does the term unsaturated fat on a food label mean?

It means the fat that contains less than the maximum number of hydrogen atoms in one or more of its fatty acid chain.