FOUNDATIONS Flashcards
opposite of medial
lateral
opposite of cranial
caudal
opposite of proximal
distal
opposite of lateral rotation
medial rotation
when pinky and thumb touch
opposition
same side of the body
ipsilateral
opposite sides of the body
contralateral
what is the largest bone of the foot
calcaneus
What are Primary cartilagenous joints
joined by hyaline cartilage
long bone epiphseal growth plates
What are Secondary cartilagenous joints
strong, joined by fibrocartilage
intervertebral discs
what type of joints are sutures and syndesmoses
fibrous
stages of embriogenesis
Gametogenesis, fertilisation, cleavage, gastrulation, formation of body plan, organogenesis
what is morphogenesis
formation of body plan
describe cleavage
earliest cell divisions. cell division is rapid, body axes are also formed
What is gastrulation
migration of cells through the primitive streak to form germ layers (Ectoderm, mesoderm, endoderm)
How fast is the innate immune response
within hours, fast
how fast is the adaptive immune response
within days, slow
what immune response is specific
adaptive
immune response is tailored to each individual antigen
which immune system displays memory
adaptive
what is the more diverse immune response
adaptive
highly diverse, respinds to a vast amount of different structures
Features of a neutrophil
multi-lobed nucleus, main target is bacteria and fungi
Features of an eosinophil
bi-lobed nucleus, stains red. targets large parasites, modulates allergic inflammatory responses
features of a basophil
large granulocyte
releases histamine for inflammatory response
difference between basophil and mast cell
basophils leave bone marrow already mature, whereas mast cell circulates in an immature form, only maturing once in a tissue site
features of lymphocytes
B Lymphocytes : release antibodies, assist in activation of T cells
T lymphocytes : mature in thymus
NK cells : kill virus infected and tumour cells
what is C-reactive protein (CRP)
Binds to microbial protein
- acts as opsonin for phagocytes
Levels rise dramatically in response to infection/inflammation
- useful clinically for monitoring of inflammatory responses
what are the roles of complement in immunity
- make holes in membranes of bacterial cells
- opsonisation and cell activation
- clearance of immune complexes
- chemotaxis
what are chemotaxis
signalling molecules that recruit WBC to site of infection
C5a, C3a
what are three pathways of complement activation
classical
lectin
alternative
what is the classical pathway of complement activation
Activated by antibodies
C1, C4, C2, C3
what is the lectin pathway
lectins bind specifically to carbohydrates
carbohydrates in cell wall of microorganisms bind to MBL
what is the alternative pathway
amplifies production of C3
what are inclusions
components synthesised by the cell itself
what are C3a and C5a responsible for
acute inflammation
describe some structural features of antibodies
large globular glycoproteins, Y shaped molecules held together by disuphide bridges
- two heavy chains
- two light chains
What Ig is pentameric? Describe some functions
IgM,
First Ig to be produced in an immune response
What is the most abundant Ig in the blood? Describe some functions
IgG
Actively transported across placenta. provides foetal immunity
What is second most abundant Ig in blood? describe some functions
IgA
secretory Ig, primary defence mechanism at mucosal surfaces
What is least abundant Ig? describe some functions
IgE
produced in response to parasitic infection, type 1 hypersensitivity
Function of IgD
unknown in secreted form
B cell antigen receptor on cell surfaces
What is the Fab fragment of an antibody involved in
Antigen binding
What is the Fc region of an antibody involved in
Responsible for major biological action of antibodies
IgE binds here in hypersensitivity type 1 reactions
Characteristics of B cells
Develop in Bone marrow, produce antibodies
Characteristics of T cells
Develop in bone marrow, mature in thymus
- CD4+ T cells - regulate innate and adaptive immune response
- CD8+ T cells - kill infected body and cancer cells
Class I MHC cells
expressed on all nucleated cells
Class II MHC
Expressed only on antigen presenting cells
Dendritic cells, macrophages, B cells
What are some physical signs of acute inflammation
Rubor, Calor, Tumor, Dolor
Describe the Vascular phase of Acute Inflammation
Vasodilation of blood vessels, increased blood vessel permeability, circulation slows and increased stasis at injury
Describe the cellular phase of acute inflammation (5)
- Margination - neutrophils line up along vessel wall
- Rolling - close contact with and rolling along vessel wall
- Adhesion - connecting to vessel wall
- Migration - neutrophils move through vessel wall to affected area in tissues (diapedesis)
- neutrophils phagocytoses pathogen
What are the major cells involved in chronic inflammation
Monocytes, macrophages, lymphocytes, plasma cells, fibroblasts
Outcomes of chronic inflammation
tissue destruction, fibrosis, necrosis
outcomes of acute inflammation
resolution, abscess formation, chronic inflammation
Define necrosis
Premature cell death by external factors, always pathological
Define apoptosis
Predefined programmed cell death, requires an energy source
removes unwanted cells and viral cells and tumour cells
What is coagulative necrosis
cell death due to a lack of blood supply
MI etc.
What is colliquative necrosis? where does it occur
partial or complete dissolution of tissue
occurs in brain
Caseuous necrosis
cheese like
Tuberculosis
Gangrenous
Necrosis with secondary infection by anaerobic bacteria
Fibrinoid necrosis
found in blood vessel walls, death of blood vessels replaced by fibrin
most common in liver
Characteristics of benign neoplasms
slow growth rate, well differentiated, normal nuceli, no invasion, no metastasis
Characteristics of malignant neoplasms
poorly differentiated, unusual mitotic figures, ill defined border, invasion and frequent metastasis
glandular benign and malignant neoplasm name
adenoma, adenocarcinoma
squamous benign and malignant neoplasm name
papilloma, squamous cell carcinoma
Fat benign and malignant neoplasm name
lipoma, liposarcoma
Smooth muscle benign and malignant neoplasm name
Leiyomyoma, Leiyosarcoma
Blood Vessel benign and malignant name
haemangioma, angiosarcoma
Bone benign and malignant neoplasm name
osteoma, osteosarcoma
Define metaplasia
change from one mature cell to another
Define hyperplasia
physiological increase in cell number (reversible) can be benign
Neoplaisa
abnormal cell proliferation not in response to a stimulus
Define hypertrophy
increase in cell size
Hypoplasia
physiological decrease in cell number
Staph aureus appearance
golden
Streptoccoci features
strips, gram positive
Test to identify staph aureus
coagulase test
+ve if staph aureus, -ve means coagulase negative staph
Test to identify streptococci
haemolysis
alpha - partial, dark green
beta - complete, yellow
gamma - no haemolysis, red
what colour does gram positive bacteria stain
purple due to thick peptidoglycan layer that stains as well as a phospolipid bilayer
what colour do gram negatie organisms stain
pink, thinner peptidoglycan wall
What can pseudomonas aeruginosa be treated with
ciproflaxin
resistant to most antibiotics
Define bactericidal and bacteriostatic
cidal - kills bacteria
static - inhibits bacterial growth
what is C.Diff treated with?
metrodizanole (mild)
vancomycin (severe)
both oral
What are the 4 Cs of C.diff infection
ciproflaxin
clinamycin
cephalosporins
co-amoxiclav
what are the 5 ways infecion is spread
inhalation, ingestion, innoculation, mother to indant, intercourse
what is MRSA resistant to
all beta-lactam antibiotics
name two aerobic gram negative organisms
nesseira gonnorhoea, nesseria meningitis
what are some antibiotics that inhibit cell wall synthesis
penicillins, cephalasporins
what are some antibiotics that inhibit protein synthesis
macrolides, aminoglycosides (gentamicin)
what are some antibiotics that act on bacterial DNA
metrodizanole (anaerobes), trimethropin +/- sulphonamide, fluoroquinolones (G+ve, G-ve)
what is transformation ABR
dead bacterial DNA is combined into living bacterial plasmid
Transduction ABR
bacterial DNA is transferred between viruses
what is mechanism of action with antibiotics with a beta-lactam ring
- bactericidal
- inhibits cross linking of peptidoglycan cell wall through bidning to penicliin binding proteins
Conjugation ABR
Plasmid DNA is transferred betweeen bacteria
advantegous mutations
what is a virus
DNA or RNA core wrapped in a capsid
How does our immune system respond to viral infection
- cytotoxic T cells reciognise virally infected DNA and can induce apoptosis of virally infected host cell
- neutralising antibodies
how to confirm pressence of a viral infection
antibody response
- IgM rises during infection
- IgG rises after infection and indicated previous exposure
PCR, Antigen detection
What is an agonist
Drug that activates the receptor to produce a response to cause a biological response
What is affinity
how readily a drug binds to a specific repector
what is efficacy
how able a drug is to produce a response when bound to its receptor
Potency
concentration/ dose of a drug required to evoke a response
what is an antagonist
drug that blocks a receptor to prevent its activation
what is a competitive antagonist
competes for the same binding site as agonist, and prevents it from binding
what is a non-competitive agonist
drug occupies an allosteric site, causes conformational change to agonists binding site
Ligand gated ion channels
agonist binds, channels open, ions flow in
G-coupled protein receptors
agonist binds to receptors extracellular domain and triggers response that involves intracellular signalling cascade involving G-proteins. coverts GDP to GTP which allows it to complete other functions
salbultamol binding to b2 receptors, beta blockers to b1 receptors
Tyrosine kinase
agonist binds to membrane receptor, series of steps ocur intracellularly, phosphorylation of targets, effects…
insulin
Nuclear receptor
agonist binds to receptor in nucleus (must be lipid soluble) causes increased or decreased gene transcription
membrane potential
separation of opposite charges across cell membrane, due to unequal distribution of Na ions and K ions
more Na out of cell and K inside
decribe the pathway of sympathetic divison in the ANS
- “Thoracic/lumbar outflow”
- Short preganglionic neurone
- At the first synapse, acetylcholine is the neurotransmitter that binds to a cholinergic (nicotinic acetylcholine) receptor on postganglionic neurone
- At the second synapse, noradrenaline is the neurotransmitter that binds to an adrenoceptor (on effector cell)
what type of receptors are Choligernic and adregernic
G-protein coupled
Describe the pathway of parasympathetic divison in the ANS
- “cranio-sacral outflow”
- Long preganglionic neurone
- At the first synapse, acetylcholine is the neurotransmitter, that binds to a cholinergic (nicotinic acetylcholine) receptor on the short postganglionic neurone
- At the second synapse, acetylcholine is the neurotransmitter, that binds to a cholinergic(muscarinic acetylcholine) receptor (on effector cell)
where in the nervous system does the ANS originate from
Sympathetic originates from T1-L2
Parasympathetic orginates from cranial nerves 3.7.9.10)
M2 receptor causes
decreased heart rate and reduced cardiac conduction velocity
M3 receptor causes
bronchoconstriction, penile erection in smooth muscle
increased secretion glandularly
Descibe the different phases of the cell cycle
G1 phase
Cell increases in size
Cellular contents are duplicated
S phase
DNA replication
Each of the 46 chromosomes (23 pairs) is replicated by the cell
G2 phase
Cell grows more
Organelles and proteins develop in preparation for cell division
M phase
Mitosis (cellular division) followed by cytokinesis (cell separation)
Formation of two identical daughter cells
what is phase where cells are quiescent
G0
Describe mitosis
- Prophase
Chromatin condenses into chromosomes
Nucleolus disappears - Prometaphase
Nuclear membrane/envelope breaks down
-> spindle fibre attach to chromosomes at site called kinetochore (on centromere of each sister chromatid) - Metaphase
Chromosomes line up along metaphase plate
NB – any error in chromosomal alignment or spindle attachment will result in cell haling further progress until problem is fixed - Anaphase
Chromosomes break at centromeres and sister chromatids move up to opposite ends of the cell - Telophase
Reformation of two nuclei, chromosomes de-condense and mitotic spindle fibres break down - Cytokinesis
Division of cytoplasm to form two new cells
what is a nucleoside
base + sugar
what is a nucleotide
base + sugar + phosphate
what end are nucleotides always added to
3’
What way does DNA polymerase work?
5’ to 3’
what enzyme unwinds double helix
Helicase
What enzyme synthesises RNA primer that starts replication
DNA primase
What enzyme combines okazaki fragments
DNA ligase
rRNA
combines with proteins to form ribosomes
tRNA
act as transducter molecules to bring amino acids together
mRNA
carries a copy of the genetic code for protein synthesis
what is a gene
region of DNA that codes for a specific protein
what functional group of AA contributes to polypeptide chain in tertiary protein structure
R group
what is transcription
DNA to mRNA
what direction is mRNA synthesised
5’-3’
how is mRNA transcript modified prior to translation
- splicing - introns spliced out
what is an anticodon
3 bases on the tRNA that are complementary to the mRNA codon
What are the functions of the two mRNA binding sites, P and A, on the ribosome
P site holds peptide chain
A site Accepts the tRNA
what are telomeres
DNA caps at chromosome ends, ensure complete replication of genome and protect coding sequences at the chromosome ends from damage
acrocentric
if P arm is so short its hard to observe
telocentric
chromosomes centromere located at terminal end of chromosome
what is acCGH
1st line chromosome test, finds polymorphisms in DNA sequence
what is a polymorphism
a variation in the human genome that has a frequency of at least 1%
what is penetrance
likelihood of having disease if you have genetic mutation
what is robertsonian translocation
two acrocentric chromosomes attach to one another
trisomy
what are reciprocal translocations
segments from two different chromosomes have been exchanged
what is prevalence
number of people that currently have a specific disease
what is incidence
number of people that catch a specific disease in a year
