Download Chemistry and Biomolecules - Ch

Chemistry and Biomolecules - Ch. 3.3
1. Carbon atoms can share _______ electrons.
4
2. What are monomers and polymers?
Monomers are the smaller building blocks that bind together to form a larger molecule
called a polymer
3. What are the four types of organic compounds that are necessary for life?
Carbohydrates, Lipids, Proteins, Nucleic Acids
4. What three elements must all carbohydrates contain?
Carbon, hydrogen, oxygen
5. What are the three types of carbohydrates? How are they different? Give an example of each.
Monosaccharide
1 ring
glucose
Disaccharide
2 rings
sucrose
Polysaccharide
3 or more rings
starch and fiber
6. How do plants get carbohydrates?
Photosynthesis
7. What do plants do with those carbohydrates?
Use them as a source of energy
Store them in the cells
8. How do animals get carbohydrates?
consume them
9. What happens to a complex carbohydrate after it is eaten?
Digestion breaks down the larger carbohydrate molecules into simple sugars can be absorbed
into the bloodstream
The bloodstream carries the simple sugars to cells throughout the body where they cross into
the cells through the cell membrane.
Inside the cells, simple sugars are used as fuel in the process of cellular respiration, releasing
energy which is stored as ATP
10. What happens to any excess carbohydrates that we consume?
extra energy is converted to fats and stored by the body
11. What are three functions of carbohydrates?
Energy source, Energy storage, Structural Support
12. What monosaccharide is the primary source of energy?
glucose
13. In what form do plants store carbohydrates?
glycogen
In what form do animals?
starch
14. What carbohydrate makes up the cell wall in plants?
Cellulose
How is this compound helpful to humans?
It is an important source of fiber for animals to stimulate the digestive system
15. What three elements must all lipids contain?
Carbon, hydrogen, oxygen
16. Name the structure to the right. Name the two types of monomers
that make it up.
Triglyceride
glycerol and three fatty acids
17. What makes lipids so energy rich?
The many C-H (carbon-hydrogen) bonds
18. When will the body use lipids for energy?
when carbohydrates are scarce
19. What happens to triglycerides in the body after they are eaten?
Digestion breaks down lipids into glycerol and fatty acids that can be absorbed into the
bloodstream
The blood stream carries the glycerol and fatty acid molecules to cells throughout the body
where the molecules cross into the cells through the cell membrane.
Then they are used as fuel for cellular respiration if there are no carbohydrates available
20. What happens to the excess lipids consumed?
stored for later use
21. What are three functions of lipids?
Energy storage, cellular membrane structure, and building vitamins and hormones
22. How are lipids helpful to a cold-climate organism?
They can build up lipids to serve as insulation and energy storage
23. What four elements must all proteins contain?
Carbon, hydrogen, oxygen, nitrogen
What fifth element is often present.
Sulfur
24. What are the building blocks of proteins?
Amino acids
25. How many different amino acids are there?
20
With only so few types of amino acids, how are so many different proteins possible?
They can be arranged in many different ways
26. How many amino acids can the body make?
12
How do we get the remaining amino acids?
We must consume them
27. When will the body use proteins for energy?
only if there is a shortage of carbohydrates or lipids
28. Describe the 5 types of proteins. Give an example of each.
Structural proteins are used for support
Ex. connective tissue and keratin that forms hair and finger nails.
Transport proteins transport many substances throughout the body
Ex. hemoglobin which transports oxygen from the lungs to the other parts of the body
Hormone proteins coordinate body activities
Ex. insulin which regulates the amount of sugar in the blood.
Contractile proteins help control movement
Ex. proteins in the muscles which help control contraction.
Enzymatic proteins accelerate the speed of chemical reactions
Ex. digestive enzymes which break down food in the digestive tract.
29. What five elements make up nucleotides?
Carbon, Hydrogen, Oxygen, Nitrogen, and Phosphorus
30. What are the building blocks of nucleic acids?
Nucleotides, which are made up of a Five carbon sugar, a Phosphate, and a Nitrogen base
31. What is the function of nucleic acids?
Store information
32. Give two examples of nucleic acids.
DNA and RNA
33. Classify each of the following compounds as a carbohydrate, lipid, protein, or nucleic acid.
Amylase - protein
DNA - nucleic acid
Glycogen - carbohydrate
Triglyceride - lipid
Sucrose - carbohydrate
Glucose - carbohydrate
Enzymes - protein
Cellulose - carbohydrate
Keratin - protein
RNA - nucleic acid
Starch - carbohydrate
Hemoglobin - protein
34. What determines the caloric value of a molecule?
Energy stored in organic molecules
35. Which of the four organic molecules that we discussed has the greatest chemical bond energy?
Lipids
36. How many calories per gram do proteins, lipids, and carbohydrates contain?
Proteins
4 calories per gram
Lipids
9 calories per gram
Carbohydrates 4 calories per gram
37. What is the body’s primary source of energy?
Carbohydrates (glucose)
If that is not available, what will the body use?
Lipids
If both of those are not available, what will the body turn to for energy?
Proteins
38. What is the purpose of a chemical reaction?
breaks down or build substances
39. Define the terms “reactant” and “product” in reference to chemical reactions.
Reactant – substances going into the reaction
Product – substances produced by the reaction
40. What does activation energy have to do with chemical reactions?
It is the amount of energy needed for a particular reaction to occur
41. Does a chemical reaction always require energy to start? Explain.
Some reactions must absorb energy to start, often this is in the form of heat
Some reactions give off energy in the form of heat or light
42. What types of processes require biochemical reactions to occur?
Grow
Develop
Reproduce
Adapt
43. What conditions can affect the rate at which a chemical reaction can occur?
Temperature
pH
Catalysts
44. Enzymes are a type of catalyst. What does that mean?
A catalyst is a substance that changes the rate of reaction or allows the reaction to occur
at a lower temperature
Enzymes are catalysts in living organisms
45. Is an enzyme consumed in a chemical reaction? Explain.
Catalysts (enzymes) are not consumed or altered in a reaction, can be used over and over.
They will release their products, return to their original shape, and become ready to act
again.
46. How does having enzymes involved in our body’s chemical reactions help us?
Enzymes speed up chemical reactions that otherwise would occur too slowly at the
body’s temperature
Reactions are able to occur at lower temperatures that are safer for our body
47. Describe three functions of enzymes.
a. Help with digestion of food
b. Help with energy storage and release (ex. Burning glucose)
c. Help with molecule synthesis (ex. Building proteins and fats)
48. What is a substrate?
what an enzyme acts upon
49. Where does the substrate fit on the enzyme?
The active site
50. What happens to the enzyme after it acts upon the substrate?
They will release their products, return to their original shape, and become ready to act
again.
51. What are four factors that can affect an enzymes activity?
Temperature
pH
enzyme concentration
substrate concentration
52. How do temperature and pH affect enzyme activity? How do extreme temperatures or pH effect
an enzyme?
With temperature and pH there is a specific range at which an enzyme will work.
At extreme an temperature or pH, an enzyme can denature (change shape and become
ineffective)
53. What happens to the reaction rate if more enzyme is added?
Reaction rate will increase
54. What happens to the reaction rate if more substrate is added?
Reaction rate will increase
55. What happens to the reaction rate if all of the enzymes are working?
Reaction rate will level off
56. Draw a diagram of an enzyme working on a substrate. Label the enzyme, enzyme-substate
complex, substrate, products, and active site.
57. What is ATP? What is its job in the cell?
ATP stands for adenosine triphosphate
ATP is the molecule that supplies energy that can be used quickly and easily by cells
58. What are the monomers that make up an ATP molecule?
A nitrogen base (adenine)
A sugar (ribose)
Three phosphate groups that are held together with high energy bonds
59. How does ATP transfer (release) energy? What does it become?
ATP releases energy by losing a phosphate group and becoming ADP
Adenosine triphosphate becomes adenosine diphosphate
When it transfers a phosphate, it transfers energy
60. How can ADP be used to store energy?
Energy is used (and stored) by reattaching a phosphate group to ADP forming ATP to
be used later.
61. Write out the two reactions in the ATP  ADP cycle.
ATP  ADP + Phosphate + Energy
ADP + Phosphate + Energy  ATP