exam 1 bio 110

1. atom '

2. molecule

3. cell

4. tissue

5. organ

6. organism

7. population

8. community

9. ecosystem

10. biosphere

levels of biological organization from smallest to largest

atom

smallest unit of an element that has the chemical properties of an element

molecule

atoms that bond with each other to form other molecules

cells

simplest unit of life that is alive, can be unicellular or multicellular

tissue

cells of the same type that associate with each other to form tissue

organ

composed of 2 or more types of tissue

ecosystem

formed by the interactions of a community of organisms with their physical environment

biosphere

all the places on Earth where living organisms exist

organism

all living things are organisms, classified as belonging to a species

population

group of organisms of the same species that occupy the same environment

community

assemblage of populations of different species

taxonomy

multiple levels in which particular species are places into progressively smaller groups that are more closely related

bacteria, archaea, eukarya

3 domains of life

domain bacteria

mostly unicellular prokaryotes that inhabit many diverse environments on Earth

domain archaea

unicellular prokaryotes that often live in extreme environments like hot springs

domain eukarya

unicellular and multicellular organisms having cells with membrane bound organelles that serve various functions

binomial nomenclature

each species has a unique scientific name ie; genus, species

genus

name is capitalized and italicized

species

not is italicized but not capitalized

genome

all of the genetic material an organism possesses

proteoome

the complete opposite set of proteins of an organism

genome carries information to the proteome

relationship between genome and proteome

evolutionary change

limbs becoming wings or flippers

chemical element

pure substance made of only one type of atom, periodic table

proton, neutron, electron

3 major subatomic particles

proton

+1, in the nucleus

neutron

no charge, in the nucleus

electron

-1, around the nucleus

identify of an element

the number if protons in the nucleus

atomic number

number of protons equal to the number of number of electrons

ion

charged atom or molecule, formed when an electron is gained or loss

isotopes

forms of atoms in which the number of neutron varies

mass

the amount of matter in something

weight

derived from the gravitational pull on a given mass

hydrogen, oxygen, carbon, nitrogen

4 major elements that make up most of the atoms in living organisms

electron shells

different energy levels and average distances where electrons are found surrounding an atom’s nucleus

first electron shell

can hold 2 electrons

second electron shell

can hold 8 electrons

valence electrons

electrons located in the outermost shell, determine how an atom interacts, reacts, and forms

similarities in rows on periodic table

all elements in the same row share the same number of electron shells

similarities in column of periodic table

share the same number of valence electrons

covalent, hydrogen, and ionic

3 types of chemical bonds

covalent bond

strongest bond, 2 atoms share a pair of valence electrons

hydrogen bond

hydrogen atom forms on polar molecule and is attracted to an electronegative atom of another molecule

ionic bond

electrons are transferred, forming ions that are attracted to each other

octet rule

the outer shell is filled with 8 electrons, so that the atom is stable

importance of hydrogen bonds

weak due to the fact they cannot share or transfer electrons, but gain strength as they come together

cation

has a positive charge because it lost an electron

anion

has a negative charge because it gained an electron

salts

an ionic compound that breaks down into charged particles called electrolytes

free radical

molecules that have single unpaired electron in it outermost shell

energy

breaks olds bonds and releases new stability when bonds form

enzymes

speeds up chemical reactions by lowering the activation energy needed

hydrophilic

molecules that like water and want to bond with water molecules

hydrophobic

molecules that don’t like water and don’t want to form with water molecules

liquid, solid, gas

the 3 states of water that require energy to change

water high specific heat

allows absorption or release of large amounts of heat energy with very little change in its own temperature

surface tension

cohesive forces between molecules at the surface cause this

acids

water ionizes into hydrogen ions and hydroxide ions, when molecules release hydrogen ions into a solution

bases

a substance that can accept hydrogen ions in water

pH scale

measure the amount of hydrogen in a solution

acidic solution

pH of 6.0 or below

basic solution

pH of 7.1 or above

neutral solution

pH of 7

organic molecules

any molecule that contains carbon atoms usually bonded to hydrogen atoms

macromolecules

large, complex organic molecules

carbon

can for 4 bonds because it has 4 electrons in its outer shell and needs 4 more

isomers

molecules that have the same formula but with different structures

stereoisomers

identical bonding relationships, but the spatial positioning of atoms is different

structural isomers

contains same atoms but in different bonding relationships

cis-isomers

atoms on the same side of a double bond

trans-isomers

atoms on opposite sides of a double bond

enantiomers

mirror image molecules

monomer

one molecule that attaches to another monomer to form polymers

polymers

a bunch of monomers together in a chain

dehydration reaction

polymers are formed when monomers lose water molecule and form together

hydrolysis reaction

breaks apart polymers when water molecule is added

carbohydrates, lipids, proteins, nucleic acids

4 major classes of organic molecules

carbon, hydrogen, and oxygen

elements that make up carbohydrates

monosaccharides

means 1 sugar, simplest sugar

disaccharide

means many sugars, many monosaccharides linked together

pentose sugars

has 5 carbons

hexose sugar

has 6 carbons

lipids

made of non polar carbon hydrogen bonds that do not mix with polar water molecules

fats, phosolipids, steroids, wax

major types of lipids

glycerol + three fatty acids

basic structure of a triglyceride

triglycerides

formed by dehydration reaction and broken down by hydrolysis

saturated fats

solid at room temperature (animal fats) linked by single bond)

unsaturated fats

liquid at room temperature (oils) linked by double bonds

phospholipid

2 hydrophobic fatty acid tails and a hydrophilic polar head

lipid bilayer

formed because phospholipids are both water fearing and water loving

steroids

cholesterol, estrogen, testosterone

amino acids

building blocks of proteins

amino group

on one side of amino acid structure which is positively charges

carboxyl group

on other side of amino acid structure that is negatively charges

r group/side chain

unique variable part of an amino acid that determines its specific chemical identity

20

how many amino acids are there

polypeptide

long continuous chain of amino acids linked together by special chemical links called peptide bonds

dehydration reaction, hydrolysis reaction

how are polypeptides formed and broken down

primary, secondary, tertiary, quaternary

4 level of protein structures