Chapter 1- Cell structure

Question 1

What are the 2 main types of cell?

Answer 1

Eukaryotic cells

Prokaryotic cells

Question 2

What are eukaryotes?

Answer 2

eg: animals, plants and fungi (largest microbe)
Contain nucleus in each cell
Complex structure
Membrane bound organelles -compartmentalisation

Question 3

What are prokaryotes?

Answer 3

Bacteria and archaea (survive extreme conditions)
No nucleus but has a plasmid and tangle of chromosomes
Very few organelles

Question 4

Why is compartmentalisation important?

Answer 4

Separates products of reactions
Keeps enzymes where they need to be
Allow for the conditions in separate cells and organelles to be met

Question 5

What are the organelles and functions of prokaryotic cells?

Answer 5

Pilli- aid movement and allow for adhesion to take place
70s ribosomes- smaller than 80s ribosomes in eukaryotes and allows for protein synthesis
Plasmids- ring of DNA that is useful in genetic modificati9on
Plasma membrane- formed from phospholipids
Cell wall- made up of peptidoglycan
Flagellum- used for movement
Tangle of chromosomes- exists within the nucleoid
Cytoplasm

Question 6

What are the organelles and their functions of eukaryotic cells?

Answer 6

Nucleus
Nuclear envelope- double membrane bound
Nucleolus- largest part in nucleus and important in ribosome production
Nucleoplasm- cytoplasm of nucleus
Chromatin- Allows for chromosome production
Nuclear pores- perforations in the nuclear envelope
Rough endoplasmic reticulum- extension of nuclear membrane and used for processing and packaging proteins
Cytoplasm- where chemical reactions take place
Secretory vesicles- involved in ejection of key material out of cell
Golgi body- involved in packaging and processing of proteins and lipids, flattened sacks of membrane
Transport vesicle- transports different substances around the cell
Smooth endoplasmic reticulum- involved in synthesis of lipids
Microtubules and centrioles- make up cytoskeleton
Lysosome- contains lysozome for destruction of broken organelles and pathogens
Mitochondria
Free floating ribosomes

Question 7

What are electron microscopes?

Answer 7

TEM- transmission electron microscope 
Uses- life science, nanotechnology
Resolution- 0.2 nm
Magnification- x 100000
SEM- scanning electron microscope
Uses- general manufacturing 
Resolution- 10nm
Magnification- x 100000

Question 8

What are laser scanning confocal microscopes?

Answer 8

Resolution- 512 x 480
Magnification- x 1000
Uses- protein structures, location of organelles

Question 9

What are optical microscopes?

Answer 9

Resolution- 200nm
Magnification- x 1000
Uses- microbiology, nanophysics

Question 10

What is the endomembrane system?

Answer 10

Network of membranes within eukaryotic cells

2 main- plasma membrane and all other organelles are membrane bound- compartmentalisation

Question 11

What are the steps in protein production and packaging?

Answer 11

1- Amino acids are bound together in the ribosomes
2- Cisternae allows for intial packaging of protein in the rough endoplasmic reticulum
3- Transport vesicle removes protein of cisternae by RER pinching off
4- Transport vesicle fuses to cisface on the Golgi body and the protein enters so the protein is modified
5- Finalised protein packages into secretory vesicles
6- Secretory vesicle fuses with plasma membrane where contents are exocytosed into blood stream

Question 12

What is the cytoskeleton?

Answer 12

3 components that act as a transport system for the cell
Microfilaments- actin, cell movement and division
Microtubule- globular proteins that form tubes and are scaffold like structures that determines shapes
Intermediate fibres- mechanical strength to maintain cell integrity