BACTERIAL AND FUNGAL HUMAN PATHOGENS AND LIFE CYCLES

Question 1

bacteria morphology

Answer 1

-light microscopy
- growing bacteria on agar
Gram positive

90% cell wall is made of peptidoglycan- rigid
Contains teichoic acid
Gram negative

10% of cell wall is made up of peptidoglycan
Does not contain teichoic acid

Question 2

features of fungal or bacteria

Answer 2

Pilus septum
Cytoplasm golgi apparatus
DNA peroxisome
Ribosome round ER
Capsule nucleus
Cell wall nucleolus
Plasma membrane lysosome
Cell membrane cytoskeleton
mitochondrion
vacuole
bud scar
BOTH
- cytoplasm
- ribosome
- cell wall
- cell membrane

Question 3

how do bacteria and fungi cause disease

Answer 3

Bacteria and fungi cause disease by: finding a host, adhering to host, colonising host cell surfaces, multiplying within the host and they have the ability to avoid/overcome the host defences.

Question 4

Adhesion

Answer 4

It can be specific (certain cells in tissues or a receptor in a ligand) or nonspecific. The bacterial/fungal ligand is called adhesin ( chemical components of capsules, cell walls or pili/fimbriae). Receptors are typically glycoproteins located on cell membranes.

Question 5

replication in bacteria and fungi

Answer 5

REPLICATION

Bacteria- replicate through binary fission, asexual, genomic DNA replicates and cell doubles in mass

Fungi- reproduce sexually and asexually

Question 6

Classification

Answer 6

Domain Dear
Kingdom King
Phylum Philip
Class Came
Order Over
Family For
Genus Good
Species Soup

Question 7

VIRAL HUMAN PATHOGENS AND LIFE CYCLES

Answer 7

Capsomers- symmetrically arranged to form an impenetrable shell (caspid) around the nucleic acid core

The symmetry is of two types:
Icosahedral
Helical

Virus morphology is determined by
Electron microscopy
Genetic makeup, size

Question 8

structure

Answer 8

DNA/RNA + capsid protein -> Nucleocapsid = Naked capsid virus

Nucleocapsid + Lipid membrane glycoproteins -> enveloped virus

Question 9

virus life cycle

Answer 9

inactive - consists of nucleic acid, capsid envelope, it is entirely dependent on external factors for chance movement and spread to infect other susceptible hosts.

Active - intracellular stage called the infectious stage, viruses can be isolated from all kinds of living things: animals, plants, fungi and bacteria.

Attachment/Adsorption -> Penetration-> Uncoating-> Biosynthesis-> Maturation and Assembly -> Release

Question 10

bacteriophage

Answer 10

Two types of bacteriophage lytic phage or temperate/lysogenic phage
Lytic- the phage replicates and lyses the host cell
Lysogenic cycle- phage DNA is incorporated into the host genome where it is passed onto the generations of viruses.

Bacteriophage growth on agar- it is known as a plaque assay, since bacteriophage eat bacteria, if Ecoli is spead onto a agar plate and a drop of the bacteriophage is placed in the dish, it is clear no bacteria will grow, this area is known as the viral plaque