life science

Question 1

plant cell

Answer 1

basic unit of life in organisms of the kingdom Plantae. They are eukaryotic cells, which have a true nucleus along with specialized structures called organelles that carry out different functions.

Question 2

animal cell

Answer 2

cell that dominates most of the tissue cells in animals. Animal cells are different from plant cells because they don’t have cell walls and chloroplasts, which are relevant to plant cells.

Question 3

organelle

Answer 3

a tiny structure within a cell that performs a specific function for that cell.

Question 4

cell membrane

Answer 4

the boundary that surrounds a cell and controls which substances can enter or leave the cell.

Question 5

cell wall

Answer 5

a stiff structure that surrounds and protects a cell; found in plant, fungus, and some bacteria cells.

Question 6

cytoplasm

Answer 6

the liquid in the inside of a living cell.

Question 7

mitochondria

Answer 7

an organelle in eukaryotic cells that is the site of cellular respiration and generates most of the cell’s ATP.

Question 8

Golgi apparatus

Answer 8

complex of vesicles and folded membranes within the cytoplasm of most eukaryotic cells, involved in secretion and intracellular transport.

Question 9

endoplasmic reticulum

Answer 9

network of membranous tubules within the cytoplasm of a eukaryotic cell, continuous with the nuclear membrane. It usually has ribosomes attached and is involved in protein and lipid synthesis.

Question 10

ribosomes

Answer 10

minute particle consisting of RNA and associated proteins found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.

Question 11

centrioles

Answer 11

a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.

Question 12

chloroplast

Answer 12

an organelle in a plant cell that turns energy from the sun into chemical energy for the plant to use.

Question 13

vesicle

Answer 13

small fluid-filled bladder, sac, cyst, or vacuole within the body.

Question 14

vacuole

Answer 14

an organelle in a plant cell that turns energy from the sun into chemical energy for the plant to use.

Question 15

nucleus

Answer 15

the center of an atom containing protons and neutrons (related term: nuclei, nuclear); a region in a cell that is surrounded by a membrane and contains genetic material.

Question 16

nuclear membrane

Answer 16

double membrane enclosing a cell nucleus and having its outer part continuous with the endoplasmic reticulum. — called also nuclear envelope. — see cell illustration.

Question 17

dna

Answer 17

found in the nucleus of a cell, a long nucleic acid molecule containing the genetic instructions for the development and functioning of all living organisms; abbreviation for deoxyribonucleic acid.

Question 18

lysosome

Answer 18

organelle in the cytoplasm of eukaryotic cells containing degradative enzymes enclosed in a membrane.

Question 19

multi-cellular organism

Answer 19

organisms that consist of more than one cell, in contrast to unicellular organisms.

Question 20

unicellular organism

Answer 20

single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of Multiple cells. Unicellular organisms fall into two general categories: prokaryotic organisms and eukaryotic organisms.

Question 21

prokaryote

Answer 21

individual microscopic organism with no nucleus.

Question 22

eukaryote

Answer 22

having complex cells in which the genetic material is contained inside a nucleus.

Question 23

cell

Answer 23

the basic unit of all living things (related word: cellular)

Question 24

tissue

Answer 24

a group of cells that works together to carry out a particular task in an organism.

Question 25

organ

Answer 25

a group of tissues that performs a complex function in a body

Question 26

organ system

Answer 26

a group of organs that work together to perform one or more functions. Each does a particular job in the body, and is made up of certain tissues.

Question 27

organism

Answer 27

individual animal, plant, or single-celled life form.

Question 28

circulatory system

Answer 28

the system that transports blood and other fluids throughout the body.

Question 29

excretory system

Answer 29

the system of the body responsible for storing and getting rid of waste products, such as urine

Question 30

digestive system

Answer 30

the system by which ingested food is acted upon by physical and chemical means to provide the body with absorbable nutrients and to excrete waste products; in mammals the system includes the alimentary canal extending from the mouth to the anus, and the hormones and enzymes assisting in digestion.

Question 31

respiratory system

Answer 31

series of organs responsible for taking in oxygen and expelling carbon dioxide. The primary organs of the respiratory system are the lungs, which carry out this exchange of gases as we breathe.

Question 32

muscular system

Answer 32

organ system consisting of skeletal, smooth and cardiac muscles. It permits movement of the body, maintains posture and circulates blood throughout the body.

Question 33

nervous system

Answer 33

the system of the body that carries information to all parts of the body: The nervous system relies on nerve cells to move electrical signals to the body from the brain, and from the body to the brain and/or spinal cord.

Question 34

sensory system

Answer 34

part of the nervous system responsible for processing sensory information. A sensory system consists of sensory neurons, neural pathways, and parts of the brain involved in sensory perception.

Question 35

fight or flight reaction

Answer 35

a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival.

Question 36

skeletal system

Answer 36

the network of solid materials that give an organism’s body its structure