Cells as the basis of life pt 1 :)

Question 1

What are the three elements of cell theory

Answer 1

1. All cells arise from a pre-existing cell
2. Cells are the smallest independent unit of life
3. All organisms are made of cells

Question 2

Differences between euk and pro cells

Answer 2

Size: Euks are bigger
Cell type: Pro are Unicellular Euk are multicellular
Membrane bound organelles: Not found in Pro
Ribsomes: both have them

Question 3

Plant vs Animal cells

Answer 3

Similarities: both euk
Differences: Cell wall in plants, Chloroplast in plants, bigger, permanent vacuoles. No lysosomes

Question 4

Describe nucleus

Answer 4

Nuclear membranes with pores it also consist of nucleolus.

Controls cell action and regulates transcription, carr genetic infromation.

Question 5

Describe cell membrane

Answer 5

Semi-permeable phospholipid bilayer
non-polar hydrophobic, fatty acid tails, and polar hydrophilic phosphate heads (that face out)

control entry/exit

Question 6

Describe cell wall

Answer 6

Rigid and supportive

not present in animal cells

Question 7

Describe the cytoplasm

Answer 7

Fluid matrix=water microtubules and microfilaments (cytoskeleton)

Question 8

Describe cytoskeleton

Answer 8

Holds everything in place, maintains cells shape, assists in cell division, and exo/endocytosis
- Supports movement of organelles and assembly of spindle fibre prior to mitosis
- Microscopic internal framework and tiny microfilaments and tubules

Question 9

Describe the Mitochondrion

Answer 9

Has a double membrane for big surface area for enzyme reactions for aerobic respiration

Also contains circular DNA

POWER HOUSE OF THE CELL

Question 10

Describe the chloroplast

Answer 10

Double membrane (stacked to increase surface area for reactions)

Used for photosynthesis also contains circular DNA

Question 11

Decribe the Rough endoplasmic reticulum (ReR

Answer 11

Flattened membranes covered in ribosomes
transport within cells and also synthesis of proteins.

Question 12

Decribe the smooth ER

Answer 12

Without ribosomes and for synthesis + transport of lipids and carbs

Question 13

Describe Golgi body(WIFI)

Answer 13

Carries out exocytosis (inter-cellular transport)
-Packages molecules into vesicle for transport

Question 14

Describe ribosomes

Answer 14

Carries out protein synthesis

Question 15

Describe a Vesicle

Answer 15

In plants, it is large and important to maintain water balance and structure
- Stores food/nutrients + water
- Transportation + export of substances via eno/exocytosis

Question 16

Describe a lysosome

Answer 16

Contains digestive enzymes for deconstruction of unwanted cellular products.

Question 17

Describe Fungal cells

Answer 17

Have cell wall
Have cell membranes different lipid structure to animal cells

Question 18

Describe the fluid mosaic model

Answer 18

fluid: membrane is semi-permeable, flexible and dynamic. Fluid-like properties allow it to break and reform
mosaic: embedded lipids, different proteins, cholesterol + carbs, carrier proteins + larger molecules

Question 19

Describe a channel protein

Answer 19

Is a doorway in cell membrane
passive movement

Question 20

Describe a carrier protein

Answer 20

Actively pumps molecules across the membrane

Question 21

Describe simple diffusion

Answer 21

Molecules move passively from high to low with the concentration gradient

Pass through membrane

Question 22

Describe facilitated diffusion

Answer 22

molecules move passively from high to low through a channel protein.

Question 23

Describe osmosis

Answer 23

The passive movement of water from high to low
Salt sucks

Question 24

Describe active transport

Answer 24

Uses carrier protein to actively pump molecules across the membrane.
low to high

Question 25

describe endocytosis and exocytosis

Answer 25

endo = molecule entering cell Receptor detects molecule. cell membrane engulfs molecule and sort of pinches of into a vessicle exo = molecule exiting cell Molecule goes to golgi body to be put inside vesicle travels to cell membrane vesicle attaches to membrane and molecule released outside cell

Question 25

describe surface area to volume ratio

Answer 25

lower surface area to volume ratio is BETTER for moving across membrane, transporting molecules etc SA/V decreases with cell division