3.2.1.4 - Structure of Prokaryotic Cells Flashcards
Identify the missing label.
Attachment protein
The nucleic acid in a virus is enclosed within a protein coat called a…
capsid
Do prokaryotes have a nucelus?
No
Most of the success of bacteria is down to…
their small size
Plasmids are useful to scientists when they perform
genetic engineering e.g. transfer of human insulin gene to bacterial cells.
Sometimes a virus will have an additional layer of lipid called a..
lipid envelope
How do bacteria store energy?
- Glycogen granules
- Oil droplets
Describe the structure of the genetic information of a prokaryotic cell.
- Main circular strand of DNA not in a nucleus
- Smaller circular pieces of DNA (plasmids)
What is the function of a plasmid?
Small, self replicating circles of DNA that give bbacteria resistance to antibiotics.
Attachment proteins can be found where on a virus?
- In the lipid envelope (if the virus has one)
- In the capsid (if the virus does not have a lipid envelope.
What are the main differences between eukaryotic and prokaryotic cells?
- Eukaryotic cells are larger
- The DNA of Eukaryotic cells is found in a nucleus.
- Eukaryotic cells have organelles with membranes (mitochondria/chloroplasts etc.)
Identify the missing label.
Large circle of DNA
What is meant by a membrane bound organelle?
An organelles that has its own phospholipid bilayer.
Identify the missing label.
Lipid envelope
Identify the membrane bound organelles of a eukaroytic cell that would not be present in a prokaryotic cell.
- Mitochondrion
- Chloroplasts
- Nucleus
- Endoplasmic reticulum
- Golgi apparatus
- Vacuoles
- Lysosomes
Identify the missing label.
Genetic material (RNA)
Identify the missing label.
Cell-surface membrane
Identify the missing label.
Capsule
Identify the missing label.
Reverse transcriptase enzyme
Identify the missing label.
Cell wall (containing murein)
The outer layer of mucilagionus slime around a bacterial cell is called the…
capsule
Do prokaryotic cells contain membrane-bounded organelles e.g. mitochondrion?
No
How small are bacteria?
0.1-10 µm
Are viruses generally bigger or smaller than bacteria?
smaller
The cell wall of bacteria contains a peptidoglycan (polysaccharide chains with peptide cross-links) called…
murein
How big is a virus?
20-300 nm
Give an example of a prokaryote
Bacteria
Are viruses alive?
No as they cannot reproduce without a host. (think MRS GREN)
Identify the missing label.
Ribosome
What is the function of the attachment proteins on a virus?
- Identificaiton of a host cell.
- Attachment to a host cell
How can some bacterial cells perform photosynthesis if they do not contain chloroplasts?
They contain ‘bacterial chlorophyll’ which is associated with the memrbane of the bacterial cell.
Is the DNA of a prokaryotic cell associated with proteins (histones)?
No
Identify the missing label.
Plasmid
Identify the missing label.
Matrix
Identify the missing label.
Cytoplasm
Prokaryotic cells contain ______ ribosomes. These are smaller than 80S ribsomes that are found in eukaryotic cells.
70S
Identify the missing label.
Capsid
How do bacterial cells divide?
binary fission
Desribe 2 aseptic techniques for growing bacteria
keep lid on
wear gloves
wash hands
use sterile pipette
flame the neck of the bottle
flame to innoculating loop
contrast a human cell with a bacterial cell
(try and think of 5 key features)
- Bacterial cell is much smaller than a human cell;
- Bacterial cell has a cell wall but human cell does not;
- Bacterial cell lacks a nucleus but human cell has a nucleus;
- Bacterial cell lacks membrane-bound organelles but human cell has membrane-bound organelles;
- Bacterial ribosomes smaller than human ribosomes / bacteria have 70S ribosomes whereas humans have 80S ribosomes;
- Bacterial DNA is circular but human DNA is linear;
- Bacterial DNA is ‘naked’ whereas human DNA is bound to histones/proteins;
Describe how bacteria divide
binary fission
replcation of DNA (circular)
division of cytoplasm to produce 2 DAUGHTER cells
each with a single copy of DNA
When growing bacteria, it is grown on agar, why is the agar boiled before pouring agar plates?
to kills unwanted bacteria that could contaminate the plate
Give 2 ways in which the DNA of prokaryotic DNA is different to arrangement of DNA in humans
Prokaryotic DNA is
- Circular (not linear)
2 Not associated with histones/proteins
- Only ONE piece of DNA
- Plasmids also present
Name the main biological molecule in a bacterial cell wall
murein or glcoprotein or peptidoglycans
name the mani biological molecule in the cell membrane
phospholipid
name the process by which prokaryotic cells divide
binary fission
compare the DNA in eukaryotes with prokaryotes
nucelotide structure same
joined by phosphodiester bond
DNA same in both
contrast the DNA in eukaryotes and prokaryotes
eukaryotic DNA longER
Eukaryotic DNA contains introns prokaryotic DNA does not
eukaryotic DNA linear, prokaryotic circular
eukaryotic DNA associated with proteins, prokaryotic DNA is not
