organelles

Question 1

prokaryotic cells

Answer 1

• oldest cell type

-small and simple

-lack nucleus

-lack membrane -bound organelles

-single celled

-single circular chromosomes (DNA) and multiple small simple plasmids(genetic material)

-simple cytoskeleton

-Prokaryotic organisms are unicellular

-The plasma membrane is surrounded by an outer cell wall.

-Many prokaryotes have flagella to enable them to move.

Question 2

eukaryotic cells

Answer 2

-Eukaryotic cells are relatively large and more complex

• They have membrane-bound organelles such as a nucleus and mitochondria

-multicellular or single celled

multiple linear chromosomes (DNA)

-not all have a cell wall only plants and fungi

-complex cytoskeleton

Question 3

Cytosol

Answer 3

is the aqueous fluid (dissolved salts and nutrients) that surrounds the organelles inside the cell

Question 4

Cytoplasm

Answer 4

-Clear fluid within cell plus all organelles
The liquid (dissolved substances) around the organelles is called the cytosol

-Moves materials throughout the cell

-Cytoplasmic streaming: The movement of the fluid substance

Question 5

Plasma Membrane

Answer 5

-Outer boundary of cell

-Protects the cell

-Composed of lipid molecules that are interspersed with tiny protein channels.

-Controls what enters and leaves the cell.

Question 6

Cell Wall

Answer 6

-Only found in plant cells

-Adds protection and support

-Made of cellulose - a complex carbohydrate

-Allows water and dissolved substances to pass through.

Question 7

Mitochondria

Answer 7

-Energy producers

-Site of cellular respiration- series of chemical reactions to make energy (ATP)

-Many mitochondria in muscle cells

Question 8

ribosomes

Answer 8

-Makes proteins in the cell

-May be free in cytoplasm or attached to endoplasmic reticulum (ER)

-All cells must produce protein

Question 9

Nucleus

Answer 9

-Controls most activities in the cell

-Contains all genetic information in the form of Deoxyribonucleic acid (DNA).

Question 9

Endoplasmic Reticulum

Answer 9

-Series of folded membranes that form sacs or tubes

-Rough ER has ribosomes attached

-Proteins made by the ribosomes are packaged and transported by the ER

-Smooth ER has no ribosomes attached.

-Smooth ER synthesises lipids and assists in manufacturing of plasma membrane.

Question 10

Golgi Bodies

Answer 10

-Also called Golgi apparatus or Golgi complex

• used for storing/ packaging and modifies protein

-Cells that make saliva or mucus have many Golgi bodies

-Site of modification, sorting, and secretion of lipids and proteins

Question 11

Lysosomes

Answer 11

-Formed by the Golgi bodies

-Contain digestive enzymes to digest unwanted particles

-Help white blood cells to destroy bacteria

-Sometimes lysosomes may destroy the entire cell. Lysosome membrane ruptures, releasing enzymes, which then digest the contents of the cell: apoptosis (cell suicide).
-break down non-functional organelles

Question 12

Plastids

Answer 12

-Organelles that contain coloured pigments
Chloroplasts

-Only found in plants/ algae

-Contain the pigment chlorophyll
Carry out the process called photosynthesis

Question 12

Cytoskeleton

Answer 12

3D structure in the cytoplasm that provides cell shape

Question 13

Vacuoles

Answer 13

-Store food, water, or waste materials

-Plant cells have large vacuoles

-Vacuoles are able to expand, taking up 50-90% of the volume of the cell.

Question 14

Why are cells so small?

Answer 14

• Cells grow to size they need to perform their specific function.
• Cells supply their entire cytoplasm with materials that enter by the plasma (cell) membrane.

-Therefore cells need a large surface area and a smaller volume to adequately supply the cytoplasm.

Question 15

Cell Theory

Answer 15

-All organisms are composed of cells (and cell products)

-All cells come from pre-existing cells

-The cell is the smallest living organisational unit

Question 16

All living things share the following attributes, remembered through the acronym MRS GREND.

Answer 16

M — movement: have some level of self-powered movement

R — respiration: the conversion of carbohydrates to a usable energy form (ATP)

S — sensitivity to stimuli: the response of an organism to its environment (e.g. plants responding to light, animals responding to external temperatures by sweating, shivering)

G — growth: an irreversible change in mass

R — reproduction: production of offspring, passing attributes from one generation to the next

E — excretion of wastes: produce wastes, such as dead cells or urine, that need to be removed

N — nutrition: intake of food or nutrients

D — DNA: the molecule that codes for the production of proteins

Question 17

For life to survive in a place, there are a set of conditions that need to be met:

Answer 17

-energy source

-liquid water

-building blocks to make necessary molecules

-stable environment

Question 18

what are cells

Answer 18

Cells are the basic structural and functional units of life.

Question 19

what if the cell increases in size?

Answer 19

it may struggle to support the higher volume, slowing nutrient absorption and waste expulsion

Question 20

why is cell size limited?

Answer 20

it is to ensure the exchange of resources and waste occurs quickly enough for the survival of the cell

Question 21

what makes a plant cell different

Answer 21

• have a cell wall

-big vacuole

-contains plastids

Question 22

what makes a animal cell different

Answer 22

• lack cell wall
• small vacuoles

Question 23

nucleolus

Answer 23

-found inside the nuclease

-functions to produce and assemble cell ribosomes

Question 24

shared organelles between prokaryotes and eukaryotes

Answer 24

cytosol

flagellum

ribosomes

cell membrane

Question 25

Peroxisome

Answer 25

Site where hydrogen peroxide and other harmful molecules are broken down