BIOLOGY

Question 1

nucleus

Answer 1

cells control centre, co-ords cells activities such as growth and reproduction. stores the cells DNA.

Question 2

nucleolus

Answer 2

stores the cells RNA and is important in the production of ribosomes.

Question 3

mitochondria

Answer 3

site of respiration using oxygen, produces ATP

Question 4

rER

Answer 4

contains many Ribosomes, important and storage of proteins.

Question 5

sER

Answer 5

important in production and storage of lipids and steroids.

Question 6

Golgi apparatus

Answer 6

works with er, important in storing and packing molecules, eg proteins in vesicles ready for transport.

Question 7

lysosomes

Answer 7

contains enzymes, some cells have conventional lysosomes and secretory lysosomes.

Question 8

plasma membrane

Answer 8

encloses the cells contents.

Question 9

cilia

Answer 9

short microscopic hair like structures, moves fluid past cell, help cell to move

Question 10

cytoskeleton

Answer 10

imp in maintaining cells shape,

Question 11

ribosomes

Answer 11

made off two sub units, made to manufacture proteins

Question 12

centrioles

Answer 12

two hollow cylinders, important in spindle formation

Question 13

peroxisomes

Answer 13

helps remove toxic substances

Question 14

fluid mosaic model

Answer 14

main components- phospholipids. form a bilayer

Question 15

role of plasma membrane

Answer 15

partially permeable, controls the transport of molecules in and out of cells.
separate contents of cells from outside envoirnment
allows cells to recognise the cell as belonging to the body.
allows molecules to bind to the receptors

Question 16

structure of DNA

Answer 16

-dna is made up of bases attached to a sugar-phosphate backbone.
-each base contains nitrogen
-double helix shape
-a to t, adenine and thymine
-c to g, cytosine and guanine

Question 17

simple diffusion

Answer 17

passive movement of substances from a high concentration to low concentration.

Question 18

osmosis

Answer 18

involves movement of solvent molecules. there is a net movement of water molecules from a solution with low solute to higher solute concentration.

Question 19

facilitated diffusion

Answer 19

involves molecules which are large and charged. these molecules can only move in and out of a cell with the help of membrane proteins, DOWN a concentration gradient

Question 20

ATP

Answer 20

when atp is converted, its now adp, it realises energy and an inorganic phosphate

Question 21

animal tissue types

Answer 21

epithelial
connective
nervous
muscle

Question 22

epithelial

Answer 22

lines body surfaces, cavities and tubules. important in absorption, secretion and protection