Ch 02 Chemical Properties Flashcards Preview

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Flashcards in Ch 02 Chemical Properties Deck (51):
1

What is an atom?

The smallest unit of matter that cannot be divided. Also smallest particle which retains properties of an element. Composed of electrons, protons, and neutrons.

2

What is atomic number?

The number of protons in the nucleus

3

What is atomic weight?

The number of protons and neutrons

4

What is an isotope?

The atom has a different number of neutrons. C12, C13, C14

5

What are the biological elements?

95% carbon, oxygen, nitrogen and hydrogen

6

What is the molecular weight of a molecule?

The sum of the atomic weight of all the atoms

7

What is radioactivity?

Unstable number of protons and neutrons

8

What is ionic bonding?

An atom that gains or loses electrons

9

What is covalent bonding?

Electron sharing H:C

10

What is hydrogen bonding?

H polar (unequal) bonding to N, O, F

11

Which type of chemical reaction releases energy?

Exothermic

12

What is one mole?

The molecular weight in grams

Ex. water 2H=2x1=2 1O=16 the molecular weight of water is 18

13

What is condensation?

Water removal AKA dehydration

14

What is hydrolysis?

Breaking molecular bonds using water

15

What are the three laws of thermodynamics?

1. E cannot be created or destroyed.

2. Entropy - no energy transformation is 100%

3. Conservation of matter

16

Are exothermic or endothermic are more likely to occur?

Exothermic because they are more chaotic

17

What element is needed for an organic molecule?

Carbon!

18

Is water organic or inorganic?

Inorganic!

19

What are four characteristics of water?

1. Polar molecule

2. A good solvent

3. Temperature buffering

4. Surface tension

20

What is the formula for pH?

pH = -log10 [H-]

21

What do acids and bases donate and accept?

Acids donate H+; accept OH-

Bases donate OH-; accept H+

22

What is an isomer?

Same chemistry, different structure

23

What is Vitamin C?

Made from glucose

24

Where is starch and glycogen made?

Starch is made by plants Glycogen is made by the liver

25

Where is cholesterol needed?

Cell membranes

26

What is the difference between unsaturated and saturated molecules.

Unsaturated = more double bonds Saturated = fully saturated with hydrogen atoms

27

What is the characteristic of polyunsaturated molecules?

the more polyunsaturated, the lower the boiling point

28

What is a glycolipid?

sugar coated lipid

29

What is meant by amphoteric?

One side likes water, the other side does not

30

What is a peptide bond?

a covalent bond that holds an amino acid protein together

31

Why is water a polar molecule?

Because of it's shape, one side is negatively charged, and the other side is positively charged

32

What is an exchange reaction?

When atoms are exchanged between two molecules AB + C -> A + BC

33

What is an oxidation-reduction reaction?

Transfer of electrons between to molecules

34

What is an enzyme?

A catalyst

35

What is a buffer?

A solution that resists pH change. Typically a weak acid or alkali with a salt

36

What is a lipid?

A fatty acid

37

What is the order of amino acids? KNOW THIS!

1. just amino acid

2. hydrogen bonds, form alpha helix and beta sheet

3. remainder of molecule

4. number of polypeptide chains

38

What results when a triglyceride is hydrolyzed?

glycerol and a fatty acid

39

What kind of bonds are in unsaturated and saturated lipids?

Unsaturated: double bonds

Saturated: single bonds, filled with H

40

What does making a lipid more polyunsaturated?

Lowers boiling poing

41

What does hydrogenating do?

Adds H where double bonds were

42

What does amphoteric mean?

A molecule that reacts as an acid or a base. Also has a hydrophillic and hydrophobic end. Usually metals are amphoteric

43

What are glycolipids?

Sugar coated lipids

44

What is the structure of ATP?

C10H16N5O13P3

A image thumb
45

Compare Purines and Pyrimidines

Purines                                         Pyrimidines

Adenine, guainine                       Cytosine, thymine, uracil

MP: 214 C                                     MP: 22 C

 

46

Define nucleic acids and what are the two types?

DNA RNA

Nucleotides of nitrogen, purine or pyrimidine, and sugar phosphate

47

What is a salt?

An ionic compund that results from the neutralization of an acid and a base. Electrically neutral.

48

What is the definition  of a carbohydrate?

Sugars, starches, or celluloses.

Release energy in animals

49

Why are lipids non-polar?

Their ends are not charged.

Not soluble in water.

50

What is the difference between D- and L- amino acids?

L amino acids are manufactured in cells

D amino acids are in bacteria

51

What is denaturation?

When nucleic acids lose their 2nd, 3rd, and 4th structures by application with a strong acid, base or salt