science

Question 1

variables

Answer 1

factors that can be changed

Question 2

Independent variable

Answer 2

change (can only be 1)

Question 3

dependent variable

Answer 3

measured

Question 4

controlled variable

Answer 4

stay the same

Question 5

bio: the hierarchical relationship

Answer 5

cells, nucleus, chromosome, gene, and DNA

Question 6

cell

Answer 6

the smallest unit of life and the building blocks of living things.

Question 7

nucleus

Answer 7

roundish structure inside a cell that contains DNA and acts as the control center for a cell.

Question 8

chromosome

Answer 8

thread-like structure inside the nucleus of a cell that contains DNA that carries genetic information. (humans have 46 chromosomes)

Question 9

Gene

Answer 9

a segment of DNA molecule with a coded set of instructions in its base sequence for a specific protein product; when expressed, it may determine the characteristics of an organism.

Question 10

DNA

Answer 10

deoxyribonucleic acid
a substance found in all living things that contain genetic information.

Question 11

DNA structure

Answer 11

alternating phosphate and sugar to form the backbone
bases attached to the nitrogenous base
subunits are called nucleotides
- Adenine
- Thymine
- guanine
- cytosine

Question 12

transcription

Answer 12

the process by which the genetic message in DNA is copied into mRNA

Question 13

translation

Answer 13

process by which the amino acids are joined in a ribosome to form protein.

Question 14

codon

Answer 14

group of 3 bases in mRNA that code for a particular amino acid.

Question 15

induced mutations

Answer 15

mutation of DNA which the cause can be identified

Question 16

mutations

Answer 16

change to DNA sequence at the gene or chromosomal level

Question 17

spontaneous mutations

Answer 17

mutation of DNA which the cause can NOT be identified

Question 18

Ionic/electrovalent bonding

Answer 18

attraction between oppositely charged ions in a chemical compound. When the valence (outside shell) electrons of one atom are permanently transferred to the other atom.

Question 19

anions

Answer 19

when an atom gains an electron, it becomes negatively charged (non-metals)

Question 20

Cations

Answer 20

when an atom loses an electron, it becomes positively charged (metals)

Question 21

shell letters (inner to outer shell)

Answer 21

K - 2 electrons
L - 8 electrons
M - 18 but happy with 8 electrons
N - 32 but happy with 8 electrons

Question 22

covalent bonding

Answer 22

when pairs of electrons are shared by atoms, becoming more stable.

Question 23

writing chemical formulae

Answer 23

iron(3) hydroxide

Fe +3 OH -1

= Fe(OH)3

Question 24

chemical reactions

Answer 24

sodium chloride + lead(2) nitrate = sodium nitrate + lead(2) chloride

Question 25

balancing equations

Answer 25

not balanced: H2 + O2 = H2O
balanced: 2 H2+ O2 = 2 H2O

Question 26

Atomic number

Answer 26

number of protons in a nucleus

Question 27

atomic mass

Answer 27

number of protons and neutrons in an atom

Question 28

group number

Answer 28

tells us the number of valence (outer shell) electrons

Li 2,1
Na 2, 8, 1
K 2, 8, 8, 1

• all group 1

Question 29

period number

Answer 29

tells us how many shells there are that contain electrons.

B 2, 3 = 2 shells
Al 2,8,3 = 3 shells

Question 30

Force

Answer 30

a force is a push, a pull, or a twist

Forces can cause an object to:
- change shape
- speed up
- slow down
- start or stop moving
- change direction

Question 31

Newtons 1st law of motion

Answer 31

• an object at rest will stay at rest unless an outside force acts upon it.
• an object that is moving will continue to move at the same speed and the same direction until an unbalanced force acts upon it.

Question 32

Newtons 2nd law

Answer 32

an object will accelerate in the direction of the unbalanced force acting on it. The size of this acceleration depends on the mass of the object and the net force acting on the object.

Question 33

Graphs

Answer 33

A velocity graph: straight line = constant speed
A distance graph: straight line = not moving

Question 34

Newtons 3rd law

Answer 34

For every action force, there is an equal and opposite reaction force.

Question 35

Mitosis

Answer 35

The process involved in the production of new cells genetically identical to the original cell

Question 36

Meiosis

Answer 36

production of gametes (egg and sperm)

Question 37

Haploid (n)

Answer 37

Having one copy of each specific chromosome in each set

Question 38

Diploid (2n)

Answer 38

having two copies of each specific chromosome in each set

Question 39

atom

Answer 39

An atom is a particle that makes up all materials. It is the smallest part of an element.

Question 40

Element

Answer 40

a substance composed of atoms with the same atomic number

Question 41

Compound

Answer 41

chemical substances made up of two or more elements that are chemically bound together in
a fixed ratio

Question 42

Mixture

Answer 42

is a material made up of two or more different substances, which are mixed but not combined
chemically.

Question 43

ion

Answer 43

An ion is an atom that has lost or gained electrons in order to become stable

Question 44

Law of conservation of mass

Answer 44

States that matter cannot be created nor destroyed in a chemical reaction.

Question 45

weight

Answer 45

Weight is a measure of the force of gravity on the mass of an
object. Weight is a downward-pulling force

Question 46

inertia

Answer 46

The tendency of an object to resist changes to its motion.