DUMS questions Flashcards
what is Boyles law
the pressure (p) of a given quantity of gas varies inversely with its volume (v) at constant temperature
what is LaPlaces law
the tension within the wall of a sphere filled to a particular pressure depends on the thickness of the sphere
what is Daltons law
a law stating that the pressure exerted by a mixture of gases in a fixed volume is equal to the sum of the pressures that would be exerted by each gas alone in the same volume.
what is Henrys law
at a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.
what is the Bohr effect
the decrease in the oxygen affinity of a respiratory pigment (such as hemoglobin) in response to decreased blood pH resulting from increased carbon dioxide concentration in the blood
what is the Haldane effect
physicochemical phenomenon which describes the increased capacity of blood to carry CO2 under conditions of decreased haemoglobin oxygen saturation
which neurotransmitter acts on muscurinic receptors and what is the action in the airway
Acetylcholine
Constricts the airways
Muscarinic receptors in airway smooth muscle cause constriction when activated. Hence the use of muscarinic antagonists like ipratropium and tiotropium in asthma and COPD to reverse this effect.
describe the difference between foetal haemoglobin and adult haemoglobin
Foetal haemoglobin is comprised of two alpha and two gamma subunits and has a higher affinity for oxygen than adult haemoglobin. This is why infants with some congenital heart defects can be asymptomatic until they are weeks old, when foetal haemoglobin is lost.
what cranial nerves carry on parasympathetic fibres
Cranial nerves II, VII, IX and X carry exclusively parasympathetic nerve fibres
what cranial nerves are only motor nerves
III,IV, VI,XI,XII
what cranial nerves are only sensory nerves
I,II, VIII
what cranial nerves are both sensory and motor
V,VII,IX,X
what is the ductus arterioles
The ductus arteriosus connects the pulmonary trunk to the aorta in the foetal circulation and closes to form the ligamentum arteriosum three weeks after birth.
what is the ductus venosus
The ductus venosus is a shunt that allows oxygenated blood in the umbilical vein to bypass the liver and is essential for normal fetal circulation. Blood becomes oxygenated in the placenta and travels to the right atrium via umbilical veins through the ductus venosus, then to the inferior vena cava.
what is the foramen oval
The foramen ovale shunts oxygenated blood from the right atrium to the left atrium, bypassing the pulmonary circulation.
what is the ligament arteriosum
is the small fibrous remnant of the fetal ductus arteriosum, located between and connecting the proximal left pulmonary artery and the undersurface of the junction of the aortic arch and descending aorta, at the aortic isthmus.
what is Neo-adjuvant treatment
treatment given before surgery to shrink the tumour for surgical removal
what is adjacent treatment
given after surgery to reduce the risk of reoccurrence
what is palliative treatment
treatment that is non curative and simply aims at improving quality of life
what is radical treatment
treatment that is curative
what are tumour suppressor genes
normal genes that inhibit cell division. If you lose both copies then cancer can form
what are proto-oncogenes
Proto-oncogenes are normal genes that stimulate cell division.
what are oncogenes
In cancer, these proto-oncogenes are changed to oncogenes which enable uncontrolled cell proliferation.
what are telomeres
Telomeres are repeats in genetic code in normal cells that mean they can only divide a certain number of times as each time they divide telomere repeats decrease. In cancer there is often a mutation that reactivates telomerase resulting in cells gaining unlimited replicative potential.
what is a holoenzyme
possess a co-factor, which is an associated substance essential for that enzyme’s function.
what is an apoenzyme
has no cofactor
what are isozymes
Isozymes are like isomers – they catalyse the same reaction but have different structures and chemical properties.
what is a zymogen
an inert substance which can be chemically converted into an enzyme.
what is gherlin
is a hormone produced by enteroendocrine cells of the gastrointestinal tract, especially the stomach, and is often called a “hunger hormone” because it increases food intake.
what is the rate limiting enzyme for glycogenesis
glycogen synthase
what is the rate limiting enzyme for glycogenolysis
glycogen phosphorylase
what is the rate limiting enzyme for gluconeogensis
fructose-1,6-bisphosphate
what is the rate limiting enzyme for lipogenesis
acetyl-coA carboxylase
what is the rate limiting enzyme for glycolysis
phosphofructikinase-1
what is the function of renin
renin is recreated by the kidneys and converts angiotensinogen to angiotensin 1
what is the function of ACE
ACE is found on plasma membranes of many cell types and converts angiotensin 1 to angiotensin 2
what is the Ig most abundant in the blood stream
IgG
what is the Ig that mediates type 1 hypersensitivity reactions
IgE
what is the Ig that is in the adaptive/humoral immune response
IgM
what Ig is responsible for the foetal immune protection
IgG - transferred across the placenta
what Ig is responsible for neonatal (less than 4 weeks old) immune protection
IgA - transferred to the neonate via colostrum and breast milk
what Ig is dominant in the secondary (memory) immune response
IgG
which cancer is associated with the c-MYC mutation
Burkitts lymphoma
what are psammoma bodies
collection of calcium found in biopsy samples of mesothelioma, a pleural malignancy caused by inhaled asbestos
what cancer is most likely to arise in non smokers
adenocarcinoma
what is a common aggressive ling cancer associated with smoking
small cell carcinoma
what is Gel and Coombs classification
for hypersensitivity reactions
what is Dukes staging system for
colorectal cancer with histological appearance
what muscle is striated
skeletal and cardiac
how is the electrical conduction for skeletal cells
- neurogenic (neuromuscular junctions)
malignant epitelial neoplasms
carcinoma
malignant neoplasms of connective tissue (bone, fat,muscle,nerve)
sarcoma
glandular neoplasms
adenocarcinomas if malignant and adenomas if benign
squamous cell neoplasms
squamous cell carcinoma if malignant or papilloma if benign
malignant bladder epithelial cancer
transitional cell carcinoma
mesenchymal benign forms of:
- fat
- bone
- cartilage
- skeletal muscle
- smooth muscle
- nerves
- blood vessels
- fat = lipoma
- bone = osteoma
- cartilage = enchrondroma
- skeletal muscle = rhabdomyoma
- smooth muscle = leiomyoma
- nerves - neurofibroma schwannoma
- blood vessels = haemangioma
mesenchymal malignant forms of:
- fat
- bone
- cartilage
- skeletal muscle
- smooth muscle
- nerves
- blood vessels
- fat = liposarcoma
- bone = osteosarcoma
- cartilage = chondrosarcoma
- skeletal muscle = rhabdomyosarcoma
- smooth muscle = leiomyosarcoma
- nerves = malignant peripheral nerve sheath tumour
- blood vessels = Angiosarcoma, Kaposi’s sarcoma
melanocytic benign cancer and malignant cancer
benign
- freckle = ephelis
- mole = naevus
malignant
- melanoma
brain (glial) benign and malignant cancer
benign = glioma malignant = gliosarcoma
what are purple cocci in clusters, coagulase positive, identified on nasal swab from asymptomatic patient
- purple = gram positive
- clusters = staphylococci
- staphylococci can be divided into coagulase positive (staph.aureus) and coagulase negative (staph epidermis, staph saprphyticus)
- staph.aureus is frequently found in the upper respiratory tract and on skin but can be an opportunistic pathogen
what are purple cocci in chains, undergoes ‘green’ haemolysis on blood agar, identified in sputum sample from patient presenting with a cough and fever
- cocci in chain are streptococci
- streptococci can be divided into alpha haemolytic (turns green on blood agar die to partial haemolysys eg strep pneumonia, Group A strep, Group B strep) and non haemolytic (eg enterococcus)
large pink bacilli identified in stool sample from patient presenting with bloody diarrhoea
- gram negative bacteria stain pink under gram stain
- large gram negative bacilli are referred to as coliform
- E.coli, like many other coliform, is a gut commensal
what is an immuonglobin with a pentameric shape
IgM
difference between bohrs law and the halide effect
- The Haldane effect describes how oxygen concentrations determine hemoglobin’s affinity for carbon dioxide
- The Bohr effect, on the other hand, describes how carbon dioxide and H+ affect the affinity of hemoglobin for oxygen.
what cell is responsible for the destruction of large parasites which cannot be phagocytosis
Mast cell
what cells are MHC-II receptors on
macrophages and dendritic cells
MHC-II are present on professional antigen presenting cells
macrophages are professional antigen presenting cells
what cells do MHC-II cells present to
CD4+ T cells
what type of hypersensitivity reaction is sarcoidosis
type IV an example of delayed hypersensitivity
what does a negative enthalpy suggest
exothermic
what does a positive enthalpy suggest
endothermic
what happens when Gibbs free energy is positive
non spontaneous (endergonic)
what happens when Gibbs free energy is negative
spontaneous (exergonic)
what is body temperature in kelvin
310K
what is precontemplation
he intends to take action in the next 6 months
what is contemplation
he intends to take action in the next 6 months and has taken some behavioural action
what is preparation
he intends to take action in the next 30 days and he has taken behavioural action
what is action
he is undergoing the action
what is maintenece
he has changed his behaviour for more than 6 months
what is the hyper polarisation phase
when K channels are open and Na channels are in the resting state
how does depolarisation occur
once the threshold is reached voltage gated Na channels open and cause depolarisation
what is the testing for looking for large deletions or duplications in the genome
array comparative genomic hybridisation
what is the definition of incidence
new cases of disease occurring in a population in a defined time period
what is the definition of morbidity rate
frequency at which the disease appears in the population
what is the definition if prevalence
number of existing cases of a disease within a population at a set point of time
what organism can appear as a golden culture on a blood agar plate
staph aureus
what is alpha heamolysis
partial or “green” haemolysis
what is beta haemolysis
complete or “yellow” haemolysis
what is gamma haemolysis
lack of haemolysis
in which step of acute inflammation do WBCs bind tightly and flatten against the vessel wall
pavementing
what type of tumour is a sarcoma
malignant connective tissue tumour
which neurotransmitter is released within the synapses between post ganglionic sympathetic neurones and their effector cells
noradrenaline
what are voltage gated ion channels
are transmembrane proteins that play important roles in the electrical signaling of cells. The activity of VGICs is regulated by the membrane potential of a cell, and open channels allow the movement of ions along an electrochemical gradient across cellular membranes
what are ligand gated ion channels
also commonly referred to as ionotropic receptors, are a group of transmembrane ion-channel proteins which open to allow ions such as Na+, K+, Ca2+, and/or Cl− to pass through the membrane in response to the binding of a chemical messenger
what is a primary cartilaginous joint
Primary cartilaginous joints are known as “synchondrosis”. The cartilage, hyaline or fibrocartilage, are usually converted to bone with age, exception to this are the joints holding the first rib to the manubrium of the sternum, and sternal synchondroses.
what are secondary cartilaginous joints
These are permanent joints called symphyses and are composed of fibrocartilage. They are considered amphiarthroses, meaning that they allow only slight movement and are all found at the skeletal midline.A flat disk of fibrocartilage connect bones and remains unossified throughout life. Example is the joint in pubic symphysis.
what are the 2 types of cartilaginous joints
synchondroses (primary cartilaginous) and symphyses (secondary cartilaginous).
where is the bifurcation of the trachea
T4/5
where is the sternal angle found
2nd rib
where is the male nipple found
T4
what nerve supplies mechanoreceptors to the upper respiratory tract
vagus nerve (CN X)
what nerve controls contraction of the diaphragm during the inspiratory phase
phrenic nerve
what nerve controls contraction and relaxation of its respective intercostal muscle
intercostal nerve
what are synarthroses joints
- Immovable
- These are fixed or fibrous joints. They’re defined as two or more bones in close contact that have no movement. The bones of the skull are an example. The immovable joints between the plates of the skull are known as sutures.
what are amphiarthroses joints
- Slightly moveable
- Also known as cartilaginous joints, these joints are defined as two or more bones held so tightly together that only limited movement can take place. The vertebrae of the spine are good examples.
what are diarthroses joints
- freely moveable
- Also known as synovial joints, these joints have synovial fluid enabling all parts of the joint to smoothly move against each other. These are the most prevalent joints in your body. Examples include joints like the knee and shoulder.
what is the ball and socket joint
Permitting movement in all directions, the ball and socket joint features the rounded head of one bone sitting in the cup of another bone. Examples include your shoulder joint and your hip joint.
what is the hinge joint
The hinge joint is like a door, opening and closing in one direction, along one plane. Examples include your elbow joint and your knee joint.
what is the condyloid joint
The condyloid joint allows movement, but no rotation. Examples include your finger joints and your jaw.
what is the pivot joint
The pivot joint, also called the rotary joint or trochoid joint, is characterized by one bone that can swivel in a ring formed from a second bone. Examples are the joints between your ulna and radius bones that rotate your forearm, and the joint between the first and second vertebrae in your neck.
what is the gliding joint
The gliding joint is also called the plane join. Although it only permits limited movement, it’s characterized by smooth surfaces that can slip over one another. An example is the joint in your wrist.
what is the saddle joint
Although the saddle joint does not allow rotation, it does enable movement back and forth and side to side. An example is the joint at the base of your thumb.
