Cell Structure and Organisation Flashcards
What is the size range of animal cells?
10 - 30 micrometers
What is the size range of plant cells?
10 - 100 micrometers
What is the size range if bacterial cells?
1 - 10 micrometers
Give three features that are found in plant cells but not in animal cells
- Cell wall
- Permanent vacuole
- Chloroplast
What is the cell membrane made out of?
Phospholipids and Proteins
How many micrometers are there in a metre?
1,000,000 micrometers
What is the purpose of the mitochondria?
To produce ATP through aerobic respiration
Name, and describe, the components of the mitochondria
- Two membranes, separated by an inter-membrane gap
- Cristae, infolds in the inner membrane
- A small circle of DNA
- 70S ribosomes
What is the purpose of Cristae in Mitochondria?
Increases the the surface area to volume ratio of the active site.
What is the function if the chloroplasts
To produce glucose from photosynthesis
What is the purpose of the Golgi apparatus/body
To modify and package proteins, before they are pinched off in vesicles
What is the structure of the Gogi Apparatus/Body
It resembles the structure of the Endoplasmic Rectilium, but more compact
What is the purpose of the ribosomes
Where mRNA and tRNA are used to form a polypeptide chain
What is the structure of the ribosomes
The ribosomes are made of a large and small subunit
What is the purpose of lysosomes
They contain harmful digestive enzymes, and release them to recycle worn out organelles, or digest material that enters the cell
What is the structure of the endoplasmic rectilium
Parallel double membranes, forming flattend sacs, with interconnected fluid filled sacs between them.
What is the structure, and purpose, of the Rough ER
Ribosomes on the outer surface
Transports proteins made in the Ribosomes
What is the purpose of the smooth ER
Synthesis and transport of lipids
What is the structure of Lysomes
Small temporary vacuoles surrounded by a single membrane
What is the structure of Centrioles
Two rings of microtubes, positioned perpendicular to each other
Give two examples of a Eukaryotic cell
Animal and plant cell
Give one example of a prokaryotic cell
Bacterial cell
What is the function of the flagellum
To assist in the bacteria movement
What is the structure of the mesosome?
In-folds in the bacteria plasma membrane
What is the function of the mesosome
It is the sight of respiration
How is the DNA stored in prokaryotic cells?
In a large loop of DNA (and sometimes in plasmids (rings of DNA))
What is a “Virion”
A virus outside of a living cell
What is the cell wall made out of in prokaryotic cells?
Peptidoglycan
Why are viruses not thought of as alive?
They are unable to reproduce on their own
What type of viruses attack bacteria?
Bacteriophages
How do viruses reproduce?
They infect the host cell with their genetic information, and take over its metabolism and multiply in the host cell
What forms can viruses genetic information take?
Single or Double stranded DNA or RNA
What is the genetic information of a virus held in?
A protein coat, called a capsid
Why are viruses called “acellular”?
Because they are not made up of cells
What is the endosymbiotic theory?
It is the idea that chloroplasts and mitochondria were both once independent bacteria, (one adapted for photosynthesis, the other for aerobic respiration) that were absorbed by larger prokaryotic cells. These then evolved to have these membrane-bound organelles, which are now identified as mitochondria and chloroplasts.
What is the evidence for the endosymbiotic theory?
- Both mitochondria and chloroplasts contain 70s ribosomes and circular DNA
- Some ancient bacteria had very fluid membranes, and there is evidence that they engulfed some smaller bacteria.
Name and describe how organelles work together in the synthesis and transport of glycoproteins.
1) Nucleus - Contains chromosomes that code for proteins
2) Nuclear Pore - Allow mRNA (messenger RNA) to leave the nucleus
3) Ribosomes - Where protein synthesis happens
4) rER - Polypeptides synthesised by the ribosomes move through the rER, before it packages them into vesicles
5) Vesicles - Keep the polypeptides together as they move through the cytoplasm
6) Golgi Body - Chemically modifies and fold the polypeptides, before packaging them
7) Cell Membrane - The newly packaged glycoproteins exit the cell through the cell membrane
Give three differences between Prokaryotic and Eukaryotic cells.
Any three from:
Size, membrane bound organelles, structure and location of genetic material, structure of ribosomes or sites of respiration.
Give three differences between Prokaryotic/Eukaryotic cells and viruses.
Any three from:
- Viruses are not made of cells
- Viruses are unable to replicate by themselves
- Viruses are not thought of alive
