Science Finals Test Grade 7

Front 1

cell

Back 1

basic unit of structure and function in living things

Front 2

microscope

Back 2

an instrument that makes small objects look bigger

Front 3

organelles

Back 3

a tiny cell structure that carries out a scientific function within the cell

Front 4

cell wall

Back 4

a rigid layer of nonliving material that surrouds the cells of plants and some other organisms

Front 5

cell membrane

Back 5

a cell structure that controls which stubstances can either enter or leave the cell

Front 6

nucleus

Back 6

a cell structure that contains nuvleic acids, the chemical instructions that direct all the cells activities

Front 7

mitochondria

Back 7

rod shaped cell structures that convert energy in food molecules to energy the cell can use to carry out its funtion[powerhouse]

Front 8

endoplasmis reticulum

Back 8

a cell structure that forms a maze of passageway in which proteins and other materials are carried from one part of the cell to another

Front 9

ribosomes

Back 9

small grain like structure in the cytoplasm of a cell where proteins are made

Front 10

golgi bodies

Back 10

a structure in a cell that recieves proteins and other newly formed materials frrom the endoplasmis reticulum, packages them, and distributes them to other parts of the cell

Front 11

cholroplasts

Back 11

a structure in the cells of plants and other organsims that captures energy from sunlight and uses it to produce food

Front 12

vacuoles

Back 12

a sac inside a cell that acts as a storage area

Front 13

lysosomes

Back 13

small round cell structure containing chemicals that break down large food particles into smaller ones [recycling are]

Front 14

compound

Back 14

2 or more elements that are chemically combined

Front 15

protein

Back 15

large organic molecule made of carbon, hydrogen, orygen, nitrogen, and sometimes sulfur

Front 16

nucleic acid

Back 16

very large organic molecule made of carbon, oxygen, hydrogen, nitrogen, and phosphorus, that contains the instructions cells need to carry out all functions of life

Front 17

lipid

Back 17

energy rich organic compound, such as fat, oil, or wax, that is made of carbon hydrogen and oxygen

Front 18

characteristic property

Back 18

a quality of a substance that never changes

Front 19

physical change

Back 19

change in a state from a sloid to a liquid

Front 20

chemical change

Back 20

change in which one or more substances combine ro break apart forming a new substance

Front 21

pure substance

Back 21

a substance mad eof only one kind of matter and having definite properties

Front 22

elements

Back 22

substance that cannot be broken down into other substances by chemical or physical means

Front 23

compounds

Back 23

a substance made of 2 or more elements

Front 24

melting

Back 24

a change in state from a solid to a liquid

Front 25

freezing

Back 25

change in state from a liquid to solid

Front 26

evaporation

Back 26

process that occurs when vaporization takes placeon the surface of a liquid

Front 27

condensation

Back 27

change in state from a gas to a liquid

Front 28

solid

Back 28

state of matter that has definite volume and definite shape

Front 29

liquid

Back 29

a state of matter that has no definite shape but has definite volume

Front 30

characteristic properties

Back 30

a quality of a substance that never changes and can be used to identify the substance

Front 31

boiling point

Back 31

the temperature at which a substance changes form a liquid to gas

Front 32

melting point

Back 32

temperature at which a substance changes from a solid to liquid

Front 33

physical change

Back 33

change in a substance that does not change its identity, forexample a chnage of state

Front 34

chemical change

Back 34

change in which one or more substances combine or break apart to form new substances

Front 35

mixture

Back 35

2 or more substances that are mixed together but not chemically combined

Front 36

heredity

Back 36

passing of traits from parents to offspring

Front 37

trait

Back 37

characteristic that an organism can pass on to its offspring through its genes

Front 38

genetics

Back 38

scientific study of heredity

Front 39

fertilization

Back 39

joining of sperm and egg

Front 40

purebred

Back 40

offspring of many generations that have the same traits

Front 41

gene

Back 41

set of information that controls a trait a segment of dna on a chromosome that codes for a specific trait

Front 42

alleles

Back 42

different forms of a gene

Front 43

dominant allele

Back 43

an allele whose trait always shows up in the organism when the allele is present

Front 44

recessive allele

Back 44

allele that is masked when a dominant allele is present

Front 45

hybird

Back 45

and organism that has 2 different alleles for a trait and organism that is heterozygous for a particular trait

Front 46

phenotype

Back 46

an organisms physical apparance or visible traits

Front 47

genotype

Back 47

an organisms genetic make up, or allele combinations

Front 48

homozygous

Back 48

having 2 identical alleles for a trait

Front 49

heterosygous

Back 49

having 2 different alleles for a trait