cells

Question 1

cells

Answer 1

the smallest unit of life. Cells are the building blocks of living things. There are many different sized and shaped cells in animals and plants, as well as single-celled organisms.

Question 2

microscope

Answer 2

an instrument for viewing small objects

Question 3

unicellular

Answer 3

describes an organism having only one cell

Question 4

multicellular

Answer 4

having many cells. Most plants and animals are multicellular.

Question 5

cell membrane

Answer 5

structure that encloses the contents of a cell and allows the movement of some materials in and out

Question 6

cytosol

Answer 6

the fluid found inside cells

Question 7

ribosomes

Answer 7

small structures within a cell in which proteins such as enzymes are made

Question 8

cytoplasm

Answer 8

the jelly-like material inside a cell. It contains many organelles such as the nucleus and vacuoles.

Question 9

metabolism

Answer 9

the chemical reactions occurring within an organism that enable the organism to use energy and grow and repair cells

Question 10

binary fission

Answer 10

reproduction by the division of an organism (usually a single cell) into two new organisms

Question 11

light microscopes

Answer 11

instrument for viewing very small objects. A light microscope can magnify things up to 1500 times.

Question 12

electron microscopes

Answer 12

instrument for viewing very small objects. An electron microscope is much more powerful than a light microscope and can magnify things up to a million times

Question 13

micrometre

Answer 13

a length of one millionth of a metre

Question 14

nanometre

Answer 14

a unit of measurement equal to one billionth of a metre

Question 15

nanotechnology

Answer 15

a rapidly developing field that includes studying and investigating cells and other objects of the smallest dimensions

Question 16

Prokaryotes

Answer 16

organism classified as belonging to the Prokaryotae kingdom

Question 17

eukaryote

Answer 17

member of the group of organisms that has a membrane around the nucleus in each of their cells

Question 18

binary fission

Answer 18

reproduction by the division of an organism (usually a single cell) into two new organisms

Question 19

cell membrane

Answer 19

the thin layer that encloeses the cytosol is the cell membrane. it also keeps the cell together and gives it shape

Question 20

nucleus

Answer 20

it is the control centre for the cell and contains DNA

Question 21

cell wall

Answer 21

it covers the plant cell and gives the cell strenght and holds them in shape

Question 22

chromosomes

Answer 22

tiny, thread-like structure inside the nucleus of a cell. Chromosomes contain the DNA that carries genetic information.

Question 23

deoxyribonucleic acid

Answer 23

the chemical substance found in all living things that encodes the genetic information of an organism

Question 24

DNA

Answer 24

the chemical substance found in all living things that encodes the genetic information of an organism

Question 25

mitosis

Answer 25

cell division process that results in new cells with the same number of chromosomes as the original cell

Question 26

clones

Answer 26

identical copy

Question 27

cytokinesis

Answer 27

the process where the cytoplasm of a cell divides to form two daughter cells

Question 28

infectious diseases

Answer 28

disease that can be transferred from one organism to another

Question 29

non-infectious diseases

Answer 29

disease that cannot be transferred from one organism to another

Question 30

antibiotics

Answer 30

substance derived from a micro-organism and used to kill bacteria in the body

Question 31

disinfectants

Answer 31

chemical used to kill bacteria on surfaces and non-living objects

Question 32

iseptics

Answer 32

mild disinfectant used on body tissue to kill microbes

Question 33

bactericidal

Answer 33

describes an antiseptic that kills bacteria

Question 34

bacteriostatic

Answer 34

describes an antiseptic that stops bacteria from growing or dividing but doesn't kill them

Question 35

phloem

Answer 35

type of tissue that transports sugars made in the leaves to other parts of a plant

Question 36

translocation

Answer 36

transport of materials, such as water and glucose, in plants

Question 37

xylem vessels

Answer 37

pipelines for the flow of water up plants. They are made up of the remains of dead xylem cells fitted end to end with the joining walls broken down. Lignin in the cell walls gives them strength.

Question 38

lignin

Answer 38

a hard substance in the walls of dead xylem cells that make up the tubes carrying water up plant stems. Lignin forms up to 30 per cent of the wood of trees.

Question 39

stomata

Answer 39

small openings mainly on the lower surface of leaves. These pores are opened and closed by guard cells. Singular = stoma.

Question 40

vacuoles.

Answer 40

sacs within a cell used to store food and wastes. Plant cells usually have one large vacuole. Animal cells have several small vacuoles or none at all