Science 9 Chapter 4 Final Exam Review Preparation

Front 1

What is the cell membrane?

Back 1

a thin, protective covering that separates the inside of a cell from its external environment and controls the flow of materials in and out of the cell

Front 2

What is the cell wall?

Back 2

a tough, rigid structure that surrounds the cell membrane of plant cells

Front 3

What are chloroplasts?

Back 3

organelles in plant cells that trap the energy from the Sun and make glucose as an energy source for the plant

Front 4

What is chromatin?

Back 4

a substance within the nucleus that contains DNA and proteins

Front 5

What is a chromosome?

Back 5

a threadlike structure in a cell nucleus that carries genes

Front 6

What is cytoplasm?

Back 6

a jelly-like substance within a cell containing organelles, water, and other life-supporting materials

Front 7

What is deoxyribonucleic acid (DNA)?

Back 7

a biological molecule found in the cell nucleus that carries genetic information; composed of sugar, phosphate, and four different bases passed on from generation to generation during reproduction

Front 8

What are the four bases found in DNA molecules?

Back 8

guanine, cytosine, adenine and thymine

Front 9

What is the endoplasmic reticulum?

Back 9

a network of membrane-covered channels within a cell that transport materials

Front 10

What are enzymes?

Back 10

proteins that help speed chemical reactions within cells

Front 11

What is a gene?

Back 11

segment of DNA located at a specific place on a chromosome, each contain information to produce proteins

Front 12

What is a gene mutation?

Back 12

a change in the specific order of the A, G, C, and T bases that make up a particular gene

Front 13

What is gene therapy?

Back 13

techniques developed to alter mutated genes in order to make them function normally

Front 14

What is the golgi body?

Back 14

an organelle that sorts and packages proteins for transport

Front 15

What are hormones?

Back 15

substances, such as proteins, released from specific glands to control particular cellular activities such as growth

Front 16

What are mutagens?

Back 16

substances or factors that can cause mutations in DNA

Front 17

What is a negative mutation?

Back 17

a mutation that harms an organism or reduces the probability that organisms with the mutation can produce offspring or survive in their environment

Front 18

What is a neutral mutation?

Back 18

a mutation that does not affect the organism or does not increase or decrease the survival rate of the organism

Front 19

What is a nuclear membrane?

Back 19

the thin outer membrane that surrounds the cell nucleus; separates the contents of the nucleus from the cytoplasm

Front 20

What are nuclear pores?

Back 20

openings in the nuclear membrane that allow only certain materials into and out of the nucleus

Front 21

What is the nucleolus?

Back 21

a membrane-free organelle that floats in the interior of the nucleus and makes ribosomes

Front 22

What is the nucleus?

Back 22

(in biology) an organelle that controls all the activities within a cell

Front 23

What is an organelle?

Back 23

a specialized cell part in which specific functions are carried out to ensure a cell's survival

Front 24

What is a positive mutation?

Back 24

a mutation that benefits an organism

Front 25

What are proteins?

Back 25

essential materials required for the cell to carry out the activities necessary for its survival

Front 26

What is a ribosome?

Back 26

an organelle without a membrane that produces proteins

Front 27

What are vacuoles?

Back 27

membrane-covered storage containers within cells

Front 28

What are vesicles?

Back 28

membrane-covered sacs that form off the ends of the endoplasmic reticulum and the Golgi body and that transport proteins, nutrients, and water into, and out of and around the inside of the cell

Front 29

What is the base pair rule?

Back 29

A=T
G=C

Front 30

How many chromosomes do humans have?

Back 30

46 (23 pairs)

Front 31

23rd Chromosome Female

Back 31

XX

Front 32

23rd Chromosome Male

Back 32

XY

Front 33

Name three specialized proteins

Back 33

enzymes, hormones, transport proteins

Front 34

What is the production of protein in an animal cell?

Back 34

1. nucleus receives message to make a protein
2. DNA message for specific protein to be copied out onto RNA
3) RNA leaves nucleus through nuclear pore
4) RNA message delivered to ribosome, which makes protein
5) Protein enters ER
6) Vesicles forms off of ER and transports protein to Golgi
7) Golgi repackages protein
8) Vesicle forms off of Golgi to carry protein to cell membrane
9) Vesicle attaches to cell membrane for transport

Front 35

What are some types of gene mutation?

Back 35

deletion, addition, substitution or change of chromosome level

Front 36

What is sickle cell anemia?

Back 36

-a genetic disorder of the blood
-substitution of the A for T in one position on the gene for protein hemoglobin

Front 37

In sickle cell anemia, why are the cell curved?

Back 37

-hemoglobin takes on a different shape
-prevents effective transport of oxygen
-blocks blood flow in blood vessels
-sickle cells have a shorter life span

Front 38

What is cystic fibrosis?

Back 38

- a mutation in the gene that codes for ion transport
- results in thick mucus in lungs
- respiratory problems

Front 39

What are some ways of treating mutations?

Back 39

drugs, surgery, gene therapy