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Flashcards in Chapter 2 Study Guide Deck (59):
1

Define Term: Element

Chemical elements are substances that cannot be split into simpler substances by ordinary chemical means

2

Define Term: Atom

units of matter of all chemical elements. An element is a quantity of matter composed of atoms of the same type.

3

Define Term: Ion

an atom that has a positive or negative charge due to an enequal number of protons and electrons

4

Define Term: Molecule

when two or more atoms share electrons, the resulting combination is called a molecule

5

Define Term: Free Radical

an electrically charged atom or group of atoms with an unpaired electron in the outermost shell

6

Define Term: Compound

a substance that contains atoms of two or more different elements

7

Define Term: Trace Element

elements present in tiny amounts (0.4% of body mass) in the body

8

Name the 12 major elements in the human body:

Oxygen, Carbon, Hydrogen, Nitrogen, Calcium, Phosphorus, Potassium, Sulfur, Sodium, Chlorine, Magnesium, Iron

9

Name the 4 most abundant elements in the human body:

Carbon, Oxygen, Hydrogen, Nitrogen

10

Name the importance of Carbon in the body:

Forms backbone chains and rings of all organic (carbon-containing) molecules: carbohydrates, lipids (fats), proteins, and nucleic acids (DNA and RNA)

11

Name the importance of Oxygen in the body

Part of water and many organic (carbon-containing) molecules; used to generate ATP, a molecule used by cells to temporarily store chemical energy.

12

Name the importance of Hydrogen in the body

Constituent of water and most organic molecules; ionized form (H+) makes body fluids more acidic.

13

Name the importance of Nitrogen in the body

Component of all proteins and nucleic acids

14

Define Term: Isotope

Isotopes are atoms of an element that have different numbers of neutrons

15

Define Term: Radioisotope

radioactive isotopes are unstable because their nuclei decay to form a simpler and thus more stable configuration

16

Define Term: Valence Electron

Electron(s) on the valence (outermost) shell

17

Define Term: Cation

a positively charged ion

18

Define Term: Anion

a negatively charged ion

19

Define Term: Ionic Bond

the force of attractice that holds together ions with opposite charges

20

Define Term: Covalent Bond

A bond where two or more atoms share electrons rather than gaining or losing them. Atoms form a covalently bonded molecule by sharing one, two, or three pairs of valence electrons. The larger the number of electron pairs shared between two atoms, the stronger the covalent bond. May form between atoms of the same element or of different elements. Most common chemical bonds in the body, and the resultant compoints form most of the body's structures.

21

Define Term: Polar Covalent Bond

A covalent bond where the sharing of electrons between two atoms in unequal -- the nucleius of one atoms attracts the shared electrons more strongly than the nucleus of the other atom. E.g. water, where the oxygen molecule attracts the electrons more strongly.

22

Define Term: Hydrogen Bond

forms when a hydrogen atoms with a partial postiive charge attracts the partial negative charge of neiboring electronegative atoms, most often larger oxygen or nitrogen atoms. Weak compared to ionic or covalent bonds.

23

Define Term: Inorganic

Usually lack carbon and are structurally simple. Their molecules also have only a few atoms and cannot be used by cells to perform complicated biological functions. Includes water and many salts, acids, and bases.

24

Define Term: Organic

always contain carbon, usually contain hydrogen, and always have covalent bonds. Most are long molecules and many are made up of long chains of carbon atoms.

25

How do you generate chemical reactions and cellular energy?

The making and breaking of chemical bonds.

26

Define Term: Polar

(chemistry) Pertaining to a compound exhibiting polarity or dipole moment, that is a compound bearing a partial positive charge on one side and a partial negative charge on the other.

27

Define Term: non-polar

(chemistry) Pertaining to a compound that is nonionic or does not dissociate into ions.
Examples of nonpolar compounds are fats and oil. Many nonpolar compounds are hydrophobic. They do not readily dissolve in water but they do in a nonpolar solvent.

28

Define Term: hydrophilic

Having an affinity for water; capable of interacting with water through hydrogen bonding; hygroscopic.

29

Define Term: hydrophobic

Lacking an affinity for water; insoluble in water; repelling water.

30

Define Term: acid

A solution is acidic if it contains a lot of hydrogen ions (H+)

31

Define Term: Base

A solution is basic (alkaline) if it contains a lot of hydroxide ions (OH-)

32

Define Term: Salt

A substance that divides in anions and cations when dissolved in water (example: sodium chloride)

33

Define Term: Solution

The result of a solute dissolved in a solvent

34

Define Term: Solvent

The medium (water) in which a solvent is dissolved to create a solution

35

Define Term: Solute

The compound that is dissolved in a solvent to create a solution

36

What are the properties of water that allow polar substances to dissolve?

Water iself is polar, so it is good at breaking bonds in polar compounts.

37

What does the pH scale refer to?

Acidity and Alkalinity.

38

What is the pH of the blood?

7.35-7.45

39

Acidic substances have a ____ pH value

low

40

Alkaline substances have a _____ pH value

High

41

Substances with a low pH value are considered ____.

Acidic

42

Substances with a high pH value are considered _____.

Alkaline (basic).

43

What are the four major classes of organic compounds in the body?

Carbohydrates, Lipids, Proteins, and Nucleic Acids.

44

Define Term: Monosaccharide. Give Examples.

Simple sugar -- glucose, fructose, ribose

45

Define Term: Dissacharide. Give Examples.

double Sugar (made up of two monosaccharides) -- Examples are sucrose, lactose, maltose

46

Define Term: Polysaccharide. Give Examples.

complex sugar (carbohydrate) -- e.g. glycogen, starch, cellulose. Not sweet.

47

What is the major blood sugar?

Glucose

48

What is the major form of carbohydrate in the body?

Glycogen

49

Describe major physiological functions of triglycerides.

most plenitful lipid (fat) in the body. Provide protection, insulation, and energy (both immediate and stored). Very concentrated form of energy. Composed of a single 3-carbon glycerol molecule and 3 fatty acid molecules.

50

Describe the major physiological functions of phospholipids.

Major component to membranes. Amphipathic, with polar head and 2 nonpolar fatty acid tails.

51

Describe the major physiological functions of steriods.

Steroids have 4 rings of carbon atoms. Steroids include: sex horomone, bile salts, some vitamins, and cholesterol. Cholesterol serves as an important component of cell membranes and as starting material for sythesizing other steroids.

52

What is the structure of phospholipids?

The polar head is a phosphate group and glycerol molecule, and the tail is two non-polar fatty acid molecules.

53

What properties allow phospholipids to form bilayers in water?

the polar head in hydrophilic and forms hydrogen bonds with water, while the aminoacid tails are hydrophobic, so they cluster together to avoid the water inside and outside the cell.

54

What are proteins made of?

Amino acids

55

What are the major physiological functions of proteins?

structural, regulatory, contractile, immunological, transport, and enzymes.

56

What are DNA and RNA?

Nucleic Acids

57

Define Term: Transcription

DNA is used to make RNA, catalyzed by RNA polymerase

58

Define Term: Translation

In translation, RNA binds to a ribosome. The mRNA nucleotide sequence specifies the amino acid sequence of the protein to be sythesized.

59

What is ATP?

The major way the cell stores energy in the high energy phosphate bond.