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1
Q

Define Term: Element

A

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

2
Q

Define Term: Atom

A

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

3
Q

Define Term: Ion

A

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

4
Q

Define Term: Molecule

A

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

5
Q

Define Term: Free Radical

A

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

6
Q

Define Term: Compound

A

a substance that contains atoms of two or more different elements

7
Q

Define Term: Trace Element

A

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

8
Q

Name the 12 major elements in the human body:

A

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

9
Q

Name the 4 most abundant elements in the human body:

A

Carbon, Oxygen, Hydrogen, Nitrogen

10
Q

Name the importance of Carbon in the body:

A

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

11
Q

Name the importance of Oxygen in the body

A

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

12
Q

Name the importance of Hydrogen in the body

A

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

13
Q

Name the importance of Nitrogen in the body

A

Component of all proteins and nucleic acids

14
Q

Define Term: Isotope

A

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

15
Q

Define Term: Radioisotope

A

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

16
Q

Define Term: Valence Electron

A

Electron(s) on the valence (outermost) shell

17
Q

Define Term: Cation

A

a positively charged ion

18
Q

Define Term: Anion

A

a negatively charged ion

19
Q

Define Term: Ionic Bond

A

the force of attractice that holds together ions with opposite charges

20
Q

Define Term: Covalent Bond

A

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
Q

Define Term: Polar Covalent Bond

A

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
Q

Define Term: Hydrogen Bond

A

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
Q

Define Term: Inorganic

A

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
Q

Define Term: Organic

A

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
Q

How do you generate chemical reactions and cellular energy?

A

The making and breaking of chemical bonds.

26
Q

Define Term: Polar

A

(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
Q

Define Term: non-polar

A

(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
Q

Define Term: hydrophilic

A

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

29
Q

Define Term: hydrophobic

A

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

30
Q

Define Term: acid

A

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

31
Q

Define Term: Base

A

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

32
Q

Define Term: Salt

A

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

33
Q

Define Term: Solution

A

The result of a solute dissolved in a solvent

34
Q

Define Term: Solvent

A

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

35
Q

Define Term: Solute

A

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

36
Q

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

A

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

37
Q

What does the pH scale refer to?

A

Acidity and Alkalinity.

38
Q

What is the pH of the blood?

A

7.35-7.45

39
Q

Acidic substances have a ____ pH value

A

low

40
Q

Alkaline substances have a _____ pH value

A

High

41
Q

Substances with a low pH value are considered ____.

A

Acidic

42
Q

Substances with a high pH value are considered _____.

A

Alkaline (basic).

43
Q

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

A

Carbohydrates, Lipids, Proteins, and Nucleic Acids.

44
Q

Define Term: Monosaccharide. Give Examples.

A

Simple sugar – glucose, fructose, ribose

45
Q

Define Term: Dissacharide. Give Examples.

A

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

46
Q

Define Term: Polysaccharide. Give Examples.

A

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

47
Q

What is the major blood sugar?

A

Glucose

48
Q

What is the major form of carbohydrate in the body?

A

Glycogen

49
Q

Describe major physiological functions of triglycerides.

A

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
Q

Describe the major physiological functions of phospholipids.

A

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

51
Q

Describe the major physiological functions of steriods.

A

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
Q

What is the structure of phospholipids?

A

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

53
Q

What properties allow phospholipids to form bilayers in water?

A

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
Q

What are proteins made of?

A

Amino acids

55
Q

What are the major physiological functions of proteins?

A

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

56
Q

What are DNA and RNA?

A

Nucleic Acids

57
Q

Define Term: Transcription

A

DNA is used to make RNA, catalyzed by RNA polymerase

58
Q

Define Term: Translation

A

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

59
Q

What is ATP?

A

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