Cell structure and Organisiation (Chapter 1)

Question 1

Define cells.

Answer 1

Cells are basic units of life.

Question 2

how can cells be seen? (microsope)

Answer 2

they can only be seen with the aid of a microscope such as light microscope and electron microscope.

Question 3

what is the living material in a cell called and what does it consists of?

Answer 3

it is called protoplasm. The protoplasm consists of the cell surface membrane, cytoplasm and nucleus.

Question 4

parts of an animal cell (list out all)

Answer 4

Nucleus, cell surface membrane, cytoplasm, chromatin, nucleoplasm, Nuclear membrane, vacuole, Mitochondrion, golgi apparatus/ Golgi body, rough endoplasmic reticulum, smooth endoplasmic reticulum, ribosomes,

Question 5

magnification of light microscope and what can be seen

Answer 5

magnification up to 1000X. Can see the nucleus, cell surface membrane, chloroplasts, cell walls, vacuoles, cytoplasm

Question 6

magnification of electron microscope and what can be seen

Answer 6

magnification more than 200 000X. Can see rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi body, ribosomes.

Question 7

function of cell surface membrane.

Answer 7

cell surface membrane is also known as plasma membrane. It is made of lipid molecules, protein groups and carbohydrate groups. It is a partially permeable membrane. It controls the movement of substances (eg. oxygen, carbon dioxide, water, salt, glucose, proteins in and out of the cell.)

Question 8

function of cell wall

Answer 8

it is made of cellulose. it is fully permeable to all substances. it serves as a protection against injury for plant cells. prevents plant cells from bursting when too much water enters them. Gives plant its regular shape.

Question 9

function of nucleus

Answer 9

contains genetic information. controls all activities in the cell such as cell growth and repairing won out parts. it consists of nuclear membrane, nucleoplasm and nucleolus. it is essential for cell division. (involves replication of DNA). Without nucleus, red blood cells of a mammal are unable to divide. Nucleus also contains chromatin that consists of DNA and proteins.)

Question 10

function of cytoplasm

Answer 10

it contains the cytosol. (jelly like substance that fills the inside of the cell and is enclosed by cell membrane.) Organelles are found in cytoplasm which has specialised functions. It is where most cell activities occur.

Question 11

function of vacuole

Answer 11

animal cell contains many small temporary vacuoles while plant cells contain a single large vacuole. Vacuoles in animal cells contain a liquid and store many amounts of substances in it. Vacuoles in plants cells contain a liquid call cell sap. Sugars, Water, mineral salts and amino acids and other substances are stored in the plant cell vacuole.

Question 12

Function of chloroplasts.

Answer 12

Chloroplasts are present in some plants cells. They are an oval shaped organelle. They contain a green pigment which is called chlorophyll. It is the site for photosynthesis, a process where plants make food using light energy from the sun.

Question 13

function of mitochondrion

Answer 13

An oval of sausage shaped organelle which generates energy through aerobic respiration. It breaks down food substances to release energy. The energy is used for cell activities such as growth and reproduction.

Question 14

function of ribosome

Answer 14

They are round and tiny structures. It is the site where proteins are made. the mRNA molecule is used to synthesize proteins which are responsible for traits. The RER transports the proteins made by ribosomes to the Golgi body to be secreted out of the cell.

Question 15

function of rough endoplasmic reticulum

Answer 15

Made up of flattened spaces lined by membranes which aRE CONTINUOUs with the nuclear membrane. found on its outer surface bcs it appears to be rough. it transports newly synthesized proteins made by ribosomes to the Golgi body to be secreted out of the cell.

Question 16

Function of smooth endoplasmic reticulum

Answer 16

Are not found on its outer surface. Synthesizes fats and steroids. Converts harmful substances such as drugs, alcohol and metabolic substances into harmless and less toxic substances through a process called detoxification..

Question 17

Function of Golgi body

Answer 17

disc-shaped organelle. it stores and modifies proteins synthesized by ER before secreting them out of the cell through vesicles