Biology-the study of life

abiotic

non living

biotic

living

example of how biotic factors depend on abiotic factors

people and plants depend on water, air and sunlight to survive

Prokaryotic cells

don’t have a nucleus but contain DNA and use asexual reproduction

Eukaryotic cells

have a nucleus and sexually reproduce. we are eukaryotic cells

asexual reproduction

one parent- bianary fission

sexual reproduction

two different parent cells unite to form one organism

7 characteristics of life

1. made up of cells

2. reproduce

3. based on a universal genetic code and grown and develop

4. obtain and use materials and energy

5. living things respond to changes in their enviornment

6. stable internal environment

7. change over time

scientific method

1. state the problem in the form of a question

2. forma. hypothesis with if… then

3. set up a controlled experiment which is the independent variable

4. record and analyze results

5. draw a conclusion

Qualitative data

data that is descriptive Ex. color and texture

Quantitative data

data in the form of numerical measurements. Ex. a count or measure

know what indepeneded and dependent variables are

3 important parts to the scientific method

1. one variable

2. control to make a comparison

3. Constant- the thing that stays the same to make sure all experiments go the same way

matter

anything that takes up space and has mass

atoms

the smallest unit of matter

subatomic particles

electrons, protons, and neutrons

elements

a pure substance that cannot be broken down into simpler substances (on the periodic table)

atomic number is

the number of protons

atomic mass is

the number of protons and neutrons

protons are equal to

electrons

compound

two or more atoms that are chemically combined/joined

inorganic compounds

no carbon

organic compounds

2 or more carbon molecules combined with other elements

molecules are

compounds that have distinct properties although not all molecules are compounds

coefficient

number in front and is the number of molecules

subscript

after a symbol and is the number of atoms

valance orbitals

rings around the nucleus that contain electrons on it

how many electrons per orbital?

1st =2 second= 8 third =8

what subatomic particle is directly involved in chemical activity?

electrons

isotopes

an atom of an element that has a different number of neutrons from the number of protons in the nucleus. this means they are unstable and give off the neutrons which are half lives. these are radioactive elements. for example C-14 has 8 neutrons instead of 6.

how many years did it take to get to 6.25 grams with a 6 year half life from 50 grams?

18 years

Carbon 14 has a half life of 5,700 years. how many years wil it take from 10 grams to 2.5 grams.

10, 5, 2.5. 5,700 times 2 = 11,400

ionic bonds

formed when one or more electrons are transferred from one atom to another

what happens when an atom looses an electron

it has a positive charge

what happens when an atom gains an electron

it has a negative charge

ions

positively and negatively charged atoms

covalent bonds

forms when electrons are shared between atoms

Van der Waals forces

weak or slight attraction(bonds) between molecules

If an ion looses an electron what is it called?

a cation

if an ion gains an electron what is it called?

an anion

cation

positive

anion

negative

what happens in covalent bonds?

two atoms each needing one or more electrons in its outer shell share a pair of electrons. sharing one or more pairs of electrons enables atoms to complete their outer shell. these covalent bonds form molecules.

non polar covalent

two identical atoms exert an equal pull on the electrons.

Polar covalent bond

unequal distribution of charge. different charges on opposite sides

example of non polar

H20

intramolecular bonds

connect atoms

inside the molecule

usually stronger

types of intramolecular bonds

ionic bonds: transfer electrons

covalent- share electrons

intermolecular bonds

connect molecules together

types of intermolecular bonds

H-bonds

H-bonds

bond between unlike charges.xane

example of h bonds

h2o and h20 bond is weak

electronegativity

an atoms attraction for shared electrons

what makes cohesion

intermolecular bonds

how to hydrogen and oxygen atoms bond

they bond when a partially negative oxygen bonds with a nearby other water molecule to the partially positive hydrogen in the other moleculeolp

polarity

a molecule that has an uneven distribution of charge

how is hydrogen bonds the weakest and the strongest

not as strong as covalent or ionic but the strongest bond between 2 or more molecules

Cohesion

the attraction of molecules of the same substance

adhesion

the attraction of molecules of different substances

The pH scale

a measurement system used to indicate the connection of positive Hydrogen ions in a solution. ranges from 1-14.

acids

solutions with a higher amount of H+ ions

bases

solutions with a higher amount of OH- ions

Acidic solutions

pH values below 7 and higher concentration than water

Basic or alkaline solutions

lower concentrations than water and have values above 7

buffers

weak acids or bases than can react with strong acids or bases to prevent sharp sudden changes in pH. maintain constant

what is OH

hydroxide

are we more acidic or basic?

acidic bc more CO2

what is the ph of blood

7.3-7.4

logarithmic

Increase or decrease of value on the scale changes by a tenfold. Ex. pH of 3 is 10 times more acidic than a pH of 4. MULTIPLY BY 10

indicators

substances that detect the presence of something.

know how to make equations equal