Honors Biology Unit 2

This is a quizlet of all of the vocab and information from unit 2!

Covalent bonds

Covalent bonds

atoms sharing a set of electrons in their outer shell

• tugging marker example

• 2 or more atoms held together by a covalent bond form a molecule

molecule

a group of atoms

polar covalent bond

electrons are shared unequally between the two atoms

polar molecule

one negative side (near the oxygen) and one positive side (near the hydrogen) to the overall molecule bc the negatively charged electrons are held more tightly by the oxygen than the hydrogen atoms

• molecule with an unequal distribution of charge, resulting in the molecule having one positive and one negative side

hydrophilic

love water

non-polar molecule

electrons are shared equally and they don’t have any poles

hydrophobic

hate water

hydrogen bond

attraction between two adjacent water molecules because of the slightly positive and negative attraction

• weak

• enable water to have unique properties

• makes water attracted to itself and other polar molecules

• without it water would boil at -80 c and freeze at -100 c

chemical reaction

a process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form or a nuclear reaction.

reactant

a substance that takes part in and undergoes change during a reaction.

cohesion

water molecules are attracted to themselves

adhesion

water molecules are attracted to other polar substances

surface tension

a liquid with a high resistance to an object

evaporative cooling

uses evaporation to help cool the air

solute

substance being dissolved in the liquid

solvent

substance doing the dissolving (usually a liquid)

solution

when one substance is dissolved in another

pH

the concentrations of H+ ions in a certain solution

pH scale

• each step on the pH scale is a factor of 10

• 1-10

• 1 = very acidic

• 5-6 = slightly acidic

• 7 = neutral

• 8-10 = slightly alkaline

• 12-14 = very alkaline

acid

a substance that forms higher concentrations of H+ ions in a solution than water does (an a lower concentration of OH-)

• taste sour

• neutralize bases

• corrode metal

• pH less than 7

base

a substance that forms lower concentrations of H+ ions in a solution than water does (and higher concentrations of OH-)

• slippery

• neutralize acids

• alkaline

• higher than 7 pH

neutral

equal amount of H+ and OH- ions

matter

anything that takes up space and has mass

chemical element

cannot be broken down into other substances

single bond

sharing one set (1 marker)

double bond

sharing two sets (2 markers)

carbohydrates

• CHO! - carbon, hydrogen, oxygen

• sucrose

• structure: monomer: monosaccharides, polymer: polysaccharides

• functions: structure (cell walls, exoskeletons), fast energy source

the 6 most common elements in living things

SPONCH!

S - sulfur

P - phosphorus

O - oxygen

N - nitrogen

C - carbon

H - hydrogen

Proteins

• CHON - carbon, hydrogen, oxygen, nitrogen

• hair, sucrase

• structure: monomer: amino acids

• function: protein channels in cell membranes, enzymes like sucrase, structural like hair, antibodies, hormones

Monomer: amino acid

Polymer: polypeptides

Lipids

• CHO - carbon, hydrogen, oxygen

• phospholipid: special lipid that creates cell membranes, one bent, outside hydrophobic

• structure: varies based on function, hydrophobic (hate water)

• functions: create cell membranes, long term energy storage, hormones, steroids, insulation

• 1 glycerol, 1-3 fatty acid chains

• long hydrocarbon chains are the signature of lipids

  • cholesterol, steroid

Nucleic Acids

• DNA & RNA

• CHONP - carbon, hydrogen, oxygen, nitrogen, phosphorus

• structure: monomer: nucleotide, nucleic acids

• function: codes for proteins

The Unique Properties Of Water

1. capillary action (creep up thin tubes)

   1. ex: food coloring example - slide 12

2. high surface tension

   1. ex: water striders can walk on water

3. it has a high heat of vaporization

   1. takes more heat energy to cause water to evaporate

4. water resists temperature change

   1. beach is hot but water is cold bc water absorbs the heat energy before it changes temperature

5. water expands when it freezes

   1. means that ice is less dense than liquid water, so float

Water is a

universal solvent!

• water’s polarity allows it to dissolve many types of solutes

Dissociation of water molecules

water molecule (2 hydrogen, 1 oxygen) split to form negative hydroxl ion (alkaline) and positive hydrogen ion (acidic)

dehydration synthesis

• clicks monomers together to form longer polymers

• happens by removing an O and H atom off one monomer, and an H atom off another, and clicking those together to form water, which floats away

• two monomers now have space to bond

hydrolysis

• “water breaking”

• breaks monomers off a polymer chain

• happens by adding a water molecule to a bond. the O and H from the water bond to the side of one monomer, and the other H from the water bonds to the other monomer. this breaks them apart

• the polymer is now shorter

glucose

• 6 carbon

• 12 hydrogen

• 6 oxygen

fructose

• 5 carbon

• 10 oxygen

• 6 oxygen

galactose

• 6 carbon

• 12 hydrogen

• 6 oxygen

lactose

glucose + galactose

sucrose

glucose + fructose

Polysaccharides

• Starch

  • this carb/polysaccharide is found in plants. it is used by plants and animals for energy

• Glycogen

  • this carb/polysacc is found in animal muscles. it is how animals store sugars

• Cellulose

  • this carb/polysacc is found in plants. it is used by plants for structure (cell walls, tree trunks). animals cannot digest it, it is fiber in our diet

maltose

glucose + glucose

Phospholipids

• a special lipid that creates cell membranes

• 2 fatty acid chains, one is bent bc double bonded carbon

• with a polar head that is hydrophobic

• makes up the cell membrane

Amino Acids

polysaccharide equation

reactant

the substance present at the start of an experiment

product

substance produced in a chemical reaction