Week 5 PBL

Infectious Microorganisms

100

What type of cells are bacteria

prokaryotes

200

Gram-positive bacteria shine purple due to

a thick peptidoglycan layer

300

Name the 2 basic bacterial shapes

Cocci - spherical

Bacilli - rods

400

name a method of virus identification

any of these:

pcr

viral culture

antigen detection

serology

500

Kochs 4 postulates

1. The microorganism must be present in all diseased individuals but not in healthy individuals 
2. The microorganism must be isolated from a diseased individual and grown in a pure culture 
3. When a healthy individual is inoculated with the cultured microorganism, the disease must develop 
4. The microorganism must be re-isolated from the inoculated, diseased individual and identified as being identical to the original microorganism 

Embryology

100

The embryonic period is

Fertilisation to 8th week of gestation

200

Neurulation is

the differentiation of the ectoderm to form the cns

300

The bilaminar embyonic disc layers and what they develop into

epiblast -> fetus and amnion

hypoblast -> yolk sac and chorion

400

Trace the path from ovulation to implantation

zygote -> 4-cell stage -> morula -> blastocyst -> implantation

500

Mesoderm differentiations and an example of what they develop into

Paraxial -> vertebrae/ribs, endotome, arthrotome, syndetome, dermomyotome

intermediate -> gonads/kidneys

Lateral plate -> heart, BV, smooth muscle of GI

Pathology of Obstruction

100

Cystic Fibrosis results in which type of obstruction due to what

luminal obstruction due to mucus

200

Examples of intramural mass

- inflammatory tumor

- fibrosis

- neoplastic tumor

300

4 ways to block a tube

1) blockage within lumen

2) intramural mass

3) extrinsic compression

4) Muscular dysfunction

400

Systemic effects of GI tract obstruction

- dehydration/infection

500

Congential example of muscular dysfunction

Hirschprungs disease (loss of nerve supply)

Genetic Mutations

100

Mutation definition

Permanent change in DNA

200

how are mutations classified

1) based on mechanism

2) based on structure

3) based on association to disease

300

Types of Chromosomal abnomalities

- Number (monosomy/trisomy etc)

- structural

- uniparental disomy

400

Types of DNA sequence variants

Synonymous

missense

nonsense

splicing

frameshift

500

NAme a diagnostic tool for genetic mutations

PCR

sanger sequencing

microarrays

massive parallel sequencing

Epigenetic Inheritance

100

Typical patterns of inheritance

autosomal dominant

autosomal recessive

x-linked

200

penetrance vs expressivity

Penetrance: proportion of people carrying a particular variant who express the condition

expressivity: range of phenotypes occuring in patients with same genotypes

300

what are some possible reasons for persistence of recessive traits?

- random mutations

- inbreeding

- instability of regions in the genome

- heterozygote advantage

400

What is the effector of genomic imprinting

dna methylation

500

Methods of non classic inheritance

Diseases caused by trinucleotide-repeat mutations Disorders caused by mutations in mitochondrial genes Disorders associated with genomic imprinting