MODULE 1: Cells as the basic of life

Question 1

what is an organelle

Answer 1

Tiny cellular structure that performs a specific function in a cell

Question 2

List the main cell types for Prokaryotic

Answer 2

DNA is naked
DNA is circular
Usually no introns
No nucleus
No membrane-bound organelles
Single chromosomes
Smaller
Structurally simple

Question 3

List the main cell types for Eukaryotic

Answer 3

DNA bound is protein
DNA is linear
Usually has introns
Has nucleus
Membrane-bound organelles
Chromosomes paired
Larger
Structurally complex

Question 4

Light microscope

Question 5

Light microscope

Answer 5

first type of microscope TOTAL MAGNIFICATION = objective lens x eyepiece

Question 6

Electron microscope and explain SEM, TEM

Answer 6

uses electron beams instead of light
Scanning (SEM): scans the surface of the specimen
Transmission (TEM): produces images of internal organelles

Question 7

Staining techniques

Answer 7

Dye allows for the staining E.g crystal violet stains the cell wall

Question 8

lighting techniques

Answer 8

Phase contrast microscopy allows scientists to gain improved image quality of cells

Question 9

function of a Cell membrane

Answer 9

Outer membrane that surrounds a cell, controls movement in and out of the cell.

Question 10

function of a cell wall

Answer 10

Tough material surrounding the cell membrane in plant cells.
Supports and protects cells.

Question 11

function of a nucleus

Answer 11

Directs cell activities
Separated from cytoplasm by nuclear membrane.
Contains genetic material DNA.

Question 12

Function of a Cytoplasm

Answer 12

The material of the cell between the cell membrane and the nucleus.
Gel-like mixture
Surrounded by cell membrane
Contains hereditary material

Question 13

Function of a Nucleus

Answer 13

Directs cell activities
Separated from cytoplasm by nuclear membrane.
Contains genetic material DNA.

Question 14

Function of a Cell wall

Answer 14

Tough material surrounding the cell membrane in plant cells.
Supports and protects cells.

Question 15

Function of a Cell membrane

Answer 15

Outer membrane that surrounds a cell, controls movement in and out of the cell.

Question 16

Function of a Mitochrondria

Answer 16

The powerhouse of the cell.
Mitochondria combine oxygen and food to produce energy in the process of cellular respiration.
Controls level of water and other materials in the cell.

Question 17

Function of a Chloroplast

Answer 17

Uses the energy in sunlight to turn water wand carbon dioxide into sugar and oxygen (a process called photosynthesis)
Usually found in plant cells.
Contains green, light-absorbing chlorophyll.

Question 18

Function of a Vacuole

Answer 18

Membrane-bound sacs for storage, digestion, and waste removal.
Contains water solution.

Question 19

Function of a Vacuole

Answer 19

Membrane-bound sacs for storage, digestion, and waste removal.
Contains water solution.
Larger in-plant cells.
Help plants maintain shape by storing water.

Question 20

Function of a Ribosome

Answer 20

Cell structure that makes protein, for proper cell functioning including cell repair and metabolism.
Found floating within the cytoplasm or attached to the (rough) endoplasmic reticulum.

Question 21

Function of a Lysosome

Answer 21

Contain digestive enzymes
Digest excess or worn out organelles, food particles and engulfed viruses or bacteria. It is known as the garbage disposal system of the cell.

Question 22

Function of a Golgi apparatus

Answer 22

Membrane stacks with transport vesicles at the perimeter. They receive, sort, store and secrete materials

Question 23

Function of a Endoplasmic Reticulum

Answer 23

Rough E.R:
Connect with the nuclear membrane and transport proteins throughout the cell, ribosomes are attached.

Smooth E.R:
Transports lipids and steroids, has no ribosomes

Question 24

Passive Transport

Answer 24

without energy

Diffusion molecules spread from areas of high concentration to areas of low concentration along a concentration gradient
E.g oxygen enters the cells needed for cellular respiration from the capillaries

Facilitated diffusion movement of particles from high to low concentration through protein channels in the cell membrane

Question 25

Passive Transport

Answer 25

without energy Diffusion molecules spread from areas of high concentration to areas of low concentration along a concentration gradient E.g oxygen enters the cells needed for cellular respiration from the capillaries Facilitated diffusion movement of particles from high to low concentration through protein channels in the cell membrane Osmosis the movement of water from high to low concentration across a semipermeable membrane until equilibrium is reacted

Question 26

Active Transport

Answer 26

with energy Endocytosis - cells take in substances from outside of the cell by engulfing them in a vesicle. Phagocytosis - plasma membrane engulfs the solid material, forming a phagocytic vesicle Pinocytosis - plasma membrane folds inwards to form a channel allowing dissolved substances to enter the cell when the channel is closed the liquid is encircled within a pinocytic vesicle. Exocytosis is the release of cellular substances contained in cell vesicles by fusion of the vesicular membrane with the plasma membrane and subsequent release of the contents to the exterior of the cell.

Question 27

What are Enzymes

Answer 27

Enzymes are organic catalysts, Enzymes are proteins made up of amino acids linked and folded to produce a three dimensional protein structure.

Question 28

Catalyst Enzyme

Answer 28

substance that speeds up or brings about a chemical change without being used up or changed in the reaction.

Question 29

Substrate Enzyme

Answer 29

the reactant on which an enzyme works.

Question 30

Lock and Key model

Answer 30

the enzyme permits it to bind at a particular site to the substrate molecule (reactant). This causes a reaction to occur. The key (substrate) fitting the lock (enzyme).

Question 31

Induced Fit model

Answer 31

when the active site slightly changes its shape to accommodate the substrate perfectly.

Question 32

why does Temperature effect activity of Enzymes

Question 32

why does Temperature effect activity of Enzymes

Answer 32

- Temperature - PH - Substrate concentration

Question 33

why does Temperature effect activity of Enzymes

Answer 33

- Temperature - PH - Substrate concentration

Question 33

why does Temperature effect activity of Enzymes

Question 34

why does Substrate effect activity of Enzymes

Question 35

why does PH effect activity of Enzymes

Question 36

why does Substrate effect activity of Enzymes

Answer 36

- Enzyme concentration increased = rate of reaction increased - Substrate concentration increased = enzyme concentration remains constant

Question 37

why does PH effect activity of Enzymes

Answer 37

- Slight pH on either side of optimum pH = reversible changes - Extreme pH variations = irreversible changes (denature)

Question 38

why does Temperature effect activity of Enzymes

Answer 38

- Low temperature = activity of enzyme is low (vice versa) - Increase in temperature = increase in kinetic energy

Question 39

What is the Saturation Point

Answer 39

vmax or max velocity/rate

Question 40

The Optimum Temperature

Answer 40

enzyme is most active

Question 41

What is Denature

Answer 41

breaking of bonds (e.g hydrogen bonds) modifying the molecule structure To much heat can cause a decrease because the enzymes become denatured The substrate no longer has an active site with which it can bind so there is little to no activity