Cells

Question 1

What are the two different type of cells?

Answer 1

Eukaryotic

Prokaryotic

Question 2

What is the characteristics of a procaryotic cell?

Answer 2

Small
Single, circular DNA
No organells 
No mitochondria, oxydative enzymes in plasma membrane
No cytoskeleton
No intracellular movement

Question 3

What are the characteristics of an eukaryotic cell?

Answer 3

Large
DNA inclosed in nuclear envelope
Organelles: mitochondria, (chloroplasts), ER, golgi, (lysosomes)
Oxidative enzymes in mitochondria
Cytoskeleton: microtubules, intermediate filaments, actin filaments
Intracellular movement

Question 4

What is the plasma membrane composed of?

Answer 4

Phospholipid bilayer plus embedded proteins

Question 5

What is the nuclear envelop?

Answer 5

The double membrane enclosing the nucleus

Question 6

Describe the meaning of fluid mosaic model

Answer 6

Its not rigid=”fluid”

Has different structures such as proteins and carbohydrates inbedded=”mosaic”

Question 7

Describe the plasmatic membrane structure and characteristics

Answer 7

Heterogenous
Consist of a double layer of phospholipids
Proteins protruding on both sides
Inpermiable to polar/charged solutes
Permeable to nonpolar compounds

Question 8

Describe the endosymbiosis theory

Answer 8

Ancestral anaerobic eukaryote engulfes aerobic bacteria, wich makes the cell able to benefit from eachother and develop into the eucaryotic cells of today

Question 9

What is the nucleus and its functions?

Answer 9

Membrane enclosed organelle
Found only in eucaryotes
Contains the DNA

Question 10

What is lisosomes and their functions?

Answer 10

Membrane bound organelle
Only in eucarotes
Is a spherical vesicle that contain hydrolytic enzymes that breaks down (lysis) biomolecules
Takes care of waste from the cytoplasm

Question 11

What is smooth ER and its function?

Answer 11

The smooth ER is a part of ER as a whole but contains no ribosomes, hence smooth
Meshwork of fine disklike tubular membrane vesicles
It synthesizes lipids, phospholipids, steroids
Metabolises carbohydrates, detoxification of metabolism products/drugs/alcohol in livercells

Question 12

What is the plasmatic membrane and its functions?

Answer 12

The double layer of phospholipids covering the cell. Regulates What is let in and out of the cell

Question 13

What is rough endoplasmatic reticulum and its functions?

Answer 13

A series of connected flattened sacs in eucaryotic cells
Contains ribosomes, hence rough
Continous with the nuclear envelope
Involved in proteinsyntesis, the proteins are modified and “matures”
Proteins leave in vesicles and go to golgi

Question 14

What is a ribosome and its functions?

Answer 14

Present in large Numbers in every living cell.
The site of protein synthesis
Can be detached to ER in eukaryotic cells
Is made of proteins and ribosomal RNA

Question 15

What is golgi-apparatus and its functions?

Answer 15

Membrane bound organelle in eukaryotic cell
Made up of flattened, stacked pouches named cisternae.
Transports, modify and pack proteins/lipids into vesicles for further transport

Question 16

What is mitochondria and What is its function?

Answer 16

Membrane bound organelle in eukaryotic cells
Generates ATP
Also store Ca++, generate heat, mediates cell growth and death
Has two distinct membranes

Question 17

What is a cytoskeleton?

Answer 17

Present in eukaryotic cells
System of filaments and fibers (actin, microtubules, intermediate)
Responsible of locomotion of the cell and organelles within it (microtubules)
The organizing of other constituents of the cell (actin)
maintains the cells shape (intermediate)