Chapter2&3

Question 1

atoms two regions

Answer 1

1. nucleus:
   protons
   -pos charge
   -number determines the type and characteristic of the atom
   nuetrons
   -no charge
2. electron shells
   -regions around the nucleus where elctrons (neh charge) exist
   -the number of electrons is associated with a type of atom can change

Question 2

shells

Answer 2

1st shell- 2 electrons
2nd- 8 electrons
3rd- 8 electrons

Question 3

atoms

Answer 3

anything that takes up space/weighs

Question 4

properties of atoms

Answer 4

1. protons attract an equal amount of electrons
2. when the outermost shell of an atom is unfilled, the atom is unstable
3. unstable atoms interact to become stable- they gain, or lose electrons
4. the amount of energy an electon holds can change

Question 5

chemical bonds

Answer 5

• interactions of electrons between atoms
• for any atom, the number of potential bonds is determined by the number of electrons needed to fill unfilled shells
• type of bond is determined by the affinity of each atom for electrons

Question 6

types of chemical bonds

Answer 6

ionic: electron transferred from one atom to another
(the result is known as an ion)
covalent bond: sharing of electrons between atoms
( the result is molecules)

Question 7

double bond

Answer 7

the sharing of two pairs of electrons results in the formation of a double bond

Question 8

polar covalent bond

Answer 8

a type pf covalent bond where electrons are not shared equally
atoms within the molecule have slight charge
ex) ozygen hydrogen bond

Question 9

bonds

Answer 9

hydrogen- 1 bond
carbon- 4 bonds
nitrogen- 3 bonds
oxygen- 2 bonds

Question 10

properties of water

Answer 10

polar covelent bonds result in:
1. water acting ad a solvent for ionic polar covalent substances
hydrophllic and hydrophobic
2. presence of hydrogen bonds

Question 11

hydrophillic

Answer 11

substances that dissolve in water (ionic)

Question 12

hydrophobic

Answer 12

substances that dont mix or dissolve in water (covalent)

Question 13

hydrogen bonds result in:

Answer 13

1. cohesion
2. high specific heat
3. high heat of vapourization
4. expansion on freezing

Question 14

two types of pH

Answer 14

acidic: donates h+ to a solution
basic: absorbs h+ from a solution

Question 15

pH scale

Answer 15

water pH = 7 (neutral)
< 7 = acidic 
> 7 = basic 
each unit represents a 10x change in h+
most chemical reactions in living things are sensitive to pH changes but many reactions in living things produce acids or bases

Question 16

buffer

Answer 16

substances that absorbs or releases H+

minimizes pH changes of solutions (do this by donating H+)

Question 17

organic molecules

Answer 17

molecules that contain carbon:
carbon atoms form 4 bonds
the characteristic of an organic molecule is affected by its functional groups (combination of particular atoms)

Question 18

hydro carbons

Answer 18

contain only C and H -hydrophillic

Question 19

alcohols

Answer 19

contain a hydroxyl functional group - hydrophobic

Question 20

organic acids

Answer 20

contain a carboxyl (COOH)

Question 21

amines

Answer 21

contain an amino acid (NH2)

Question 22

amino acid

Answer 22

contain an amino and a carboxyl group

Question 23

polymers

Answer 23

large molecules consisting of smaller repeated units (monomers)
monomers are bonded together through the process of dehydration synthesis

Question 24

hydrolysis

Answer 24

removal of monomers from a polymer

Question 25

3 main groups of organic molecules

Answer 25

1. carbohydrates 2. proteins 3. ?

Question 26

carbohydrates

Answer 26

contain numerous hydroxyls (OH) and a carbonyl (=O) | used for: energy structure

Question 27

ploysaccharides

Answer 27

polymers of carbohydrates | starch, glycogen, cellulose

Question 28

chitin

Answer 28

is the main structural component of exoskeletons and fungi cells

Question 29

lipids

Answer 29

hydrophobic organic compounds

Question 30

main functions of lipids

Answer 30

1. energy storage 2. membrane structure 3. vitamins 4. chemical signaling (hormones)

Question 31

fats

Answer 31

lipids made of 1 glycerol molecule and 3 fatty acids | main function is energy storage but also used in water proofing and temp regulation

Question 32

fatty acids

Answer 32

long chain organic acids | 2 types: saturated and unsaturated

Question 33

white and brown fat tissue

Answer 33

brown: not as much of this, heats body by burning fat, cellular reproduction, lots of blood vessels -when you're young

Question 34

waxes

Answer 34

long carbon chain hydrophobic molecules used as waterproof coating malleable: change shape under pressure

Question 35

phospholipids

Answer 35

gycerol molecule with: 2 fatty acids and a phosphate group (PO4) hydrophillic principal component of membranes

Question 36

lipids with ring structure

Answer 36

``` diverse functions pigments membrane structures vitamins hormones (steroids) ```

Question 37

high levels of cholesterol in the blood can lead to

Answer 37

a hardening and narrowing of the arteries

Question 38

proteins

Answer 38

most diverse molecules in living organisms | polymers of amino acids

Question 39

how many types of different amino acids

Answer 39

``` 20 side chains contain: polar covalent bonds covelent bonds ionic bonds ```

Question 40

structure of protein

Answer 40

primary: amino acid sequence secondary: coiling or folding pattern teriary: overall three dimensional shape

Question 41

a protein depends on

Answer 41

its shape to create its function

Question 42

proteins shape depends on

Answer 42

1. the amino acid sequence 2. enviornmental conditions 9pH, salt concentration, temp, water content) 3. interactions with other molecules the shape of a protein can change

Question 43

functions of proteins

Answer 43

1. structure 2. storage 3. movement 4. defense 5. signaling hormones 6. transport 7. enzymes

Question 44

enzymes

Answer 44

control the rate of chemical reactions

Question 45

chemical reactions

Answer 45

rearrangement of bonds between molecules

Question 46

reaction with an enzyme

Answer 46

active sites: bind reactants

Question 47

binding of reactants causes

Answer 47

the enzyme to change shape

Question 48

once the product is formed

Answer 48

it can no longer bind to the enzyme. the enzyme returns to its original shape

Question 49

enzymes act as

Answer 49

catalysts: increases the rate of chemical reactions but are not modified

Question 50

if the enzyme cannot bind to the reactant

Answer 50

no chemical reaction occurs

Question 51

feedback control

Answer 51

regulates rates of reactions

Question 52

when the concentration of the product is high

Answer 52

the rate of the reaction is low

Question 53

when the concentration of the product is low

Answer 53

the rate of the reaction is high ( this leads to homeostatis of reactants and products)

Question 54

denaturing proteins

Answer 54

permanently changing the shape of the protein caused by chnages in pH, salt concentration water content, chemical reactions