To Remember Flashcards
What disease is linked with autoimmune destruction of ACh receptors?
Myasthenia Gravis
Where is appetite controlled?
In the arcuate nucleus (group of neurones) in the hypothalamus
Is what type of muscle would you find diads?
Cardiac
In what type of muscle would you find triads?
Skeletal muscle
What is there an absence of if someone suffers from duchenne’s disease?
Dystrophin
What is BMR and what is its role?
Basal metabolic rate. The minimal rate of energy expenditure.
Maintains the resting activities of the body by:
Maintenance of cells
Function of organs
Maintaining body temp
What are the three components of daily energy expenditure?
Energy to support our basal metabolism - BMR
Energy for voluntary physical exercise
Energy we require to process food we eat (thermogenesis)
How do work out BMI?
Weight (kg)/height squared (m)
Why is homeostasis?
The maintenance of a stable environment
What peptide hormone is released from the small intestine?
PYY
What is a good way of remembering the cause for duchenne’s disease?
It is also know as duchenne’s muscular DYSTROPHY. It is a disorder of DYSTROPHIN.
Good way of remembering the causes of atrophy? - what are they?
DAD. D - disuse A- age D- dinervation (doesn’t receive contractile signals required to maintain normal size.)
What are the 3 layers of the adrenal glands?
Zona glomerulosa, fasiculata and reticularis..as you get closer to the medulla
What is released from the zona glomerulosa? Give an example
Mineralcorticoids - SALT - aldosterone
What is released from the zona reticularis? Give an example
Glucocorticoids and androgens - SEX - testosterone
What is released from the zona fasiculata? Give an example
Glucocorticoids - SUGAR - cortisol (regulates carbohydrate metabolism.)
What effect does cortisol have on metabolism ? What does this lead to? When is this important?
Increases lipolysis, gluconeogenesis, glycogenolysis and proteolysis (not in liver)
Increase in FA, Glucose and AA
During the running of a marathon if glucose stores run out
What hormones are released from the hypothalamus?
Thryrotropin releasing hormone, corticotrophic releasing hormone, somatotropin releasing hormone, somatostatin
Where is ghrelin released from?
Wall of an empty stomach
Where is kept in released from? What affect does it have on appetite?
Adipocytes. Stimulates inhibitory neurone and inhibits stimulatory hormones.
Where is PYY released from? What is its role?
Walls of the small intestine. Opposite to ghrelin, suppresses appetite by inhibiting stimulatory hormone.
What is Cushing’s syndrome caused by?
High levels of glucocorticoids (excess cortisol.) Hyper function of the adrenal cortex.
Usually caused by long term treatment with glucocorticoids (steroids) - affect the kidney.
Can be due to a melanoma or carcinoma of the adrenal glands.
What is the internodal membrane and where is it found?
It is the membrane that wraps around the axon underneath a Schwann cell
What are the 5 types of glial cells you are expected to remember?
Astrocytes, Oligodendrocytes and ependymal cells
Microglia and Schwann cells
What is the role of microglia?
They are the macrophages of the nervous system. They have immune and inflammatory functions.
What is the role of astrocytes?
Maintain the blood brain barrier
Assist in transfer of nutrients and waste
What is the role of Oligodendrocytes?
Produce myelin sheath for the central nervous system
What is the role of ependymal cells?
Produce cerebral and spinal fluid
Where are myelinated neurones found?
On the nerves in the CNS of the autonomic NS
On all nerves of the somatic NS
The somatic and autonomic NS are both composed of what types of nerves?
Efferent
What is the role of reticular cells?
Synthesise reticular fibres and surround them with cytoplasm. Direct the T and B lymphocytes to specific regions within the lymphatic tissues.
What is proliferation?
When a stem cell divides into 2 and one replaces the original stem cell and the other goes on to differentiate.
Where is erythropoietin produced? What effect does it have?
Kidneys. Acts on e-progenitor cells in bone producing more RBCells which leads to high oxygen tissue.
What are the main Cells found for allergic reactions?
Mast cells and basophils. Both have heparin and histamine.
Eosinophils
What is the disease caused by hypothyroidism?
Hashimotos disease
What are the symptoms of hashimotos’ disease?
SLOW Reduced BMR, Cold Bradycardia Tired and lethargic Put on weight
What is the disease caused by hyperthyroidism?
Graves’ disease
What are the symptoms of graves disease ?
Increased BMR, heat intolerance
Tachycardia
Weight loss
Physical (&mental) hyperactivity
What is the role of alkylating agents? What are they an example of?
Remove a base. An example of an induced mutation
What are examples of induced mutations?
X-rays
Uv radiation
Alkylating Agents
Acridine agents
What is an acridine mutation?
One where a base is either added or removed.
What are spontaneous mutations due to?
Errors in DNA replication
DNA bases having slight chemical instability
What is the difference between a mutagen and a carcinogen?
A mutagen is a chemical which causes a mutation.
A carcinogen is a chemical that causes cancer.
What is the name given to the trait most common in a population?
Wild type
What is apparent when sickle cell disease undergoes southern blotting?
There are less DNA fragments because the restriction site for a certain enzymes is destroyed. This means that the DNA can’t be digested as much so there will be less fragments.
What are the different tests available for the detection of mutations in genes?
Southern blotting, microarray analysis, sequencing (but this is expensive)
What is inversion of a chromosome?
No loss of genetic information but a rearrangement of genetic material
Why would a ring chromosome form?
Due to the loss of telomeres or end of both arms
What is an isochromosome?
When 2 non identical chromosomes form.
One is the combination of 2 short arms and the other is the combination of 2 long arms.
What are the three names for the different types of chromosomes and what are they?
Metacentric - meta- meat sliced evenly - both the p and q arm are if the same length
Acrocentric - think A so first one - the p arm is very short, often not seen. Can undergo robertsonian translocation
Sub-metacentric- sub - lower bit is bigger. Q arm is bigger than the p arm.
What is translocation and what are the two types?
The breakage and reformation of chromosomes such that DNA is exchanged between the two chromosomes.
Reciprocal and Robertsonian
What is a robertsonian translocation?
When two acrocentric chromosome break near the centomere and one super chromosome forms. There is loss of the p arms.
What is reciprocal translocation?
When there is an exchange of material between two non homologous chromosomes.
What is the difference between calcitriol and vitamin D’s affects on serum calcium levels?
Short term regulation- PTH
Long term regulation - calcitriol
What are some of the symptoms related with metabolic syndrome?
Insulin resistance (t2 diabetes), glucose intolerance, hypertension, dyslipidaemia
What is dyslipidaemia?
Problems with lipids. In metabolic syndrome this is an increase in VLDLs and LDLs and a decrease in HDLs.
What is type 2 diabetes treated with? What does this prevent?
Metformin. Prevents gluconeogenesis (normally the low levels of insulin promote PEPCK and fructose -1,6-BP which stimulates gluconeogenesis).
What is a HbA1C test? What does it measure? What is it used for?
A test that tests for the amount of glycosylated haemoglobin (the amount of glucose that attaches to red blood cells). It is used in the diagnosis of diabetes as well as to monitor the disease.
Which tissues have an absolute requirement for glucose?
WBCells, RBCells, Kidney medulla, Lens of the eye
How is insulin given to a patient with diabetes? Why?
Intravenously. Because insulin is a peptide hormone and it would be digested in the stomach.
Describe the structure of glucagon
Single chain polypeptide hormone, lacking disulfide bridges so has a flexible 3D structure
What are the tissues that don’t require insulin to utilise glucose?
Peripheral nerves, the eye, the kidney
In hyperglycaemia what reaction takes place in the kidney ? What effect does the reaction have and what is it similar to?
Glucose is converted to sorbitol by the enzyme aldosterone reductase. NADPH a is required and NADP+ is produced.
This depletes the NADPH stores which leads to the formation of disulphide bonds.
The reaction is similar to the conversion of galactose to galactitol.
What are the macrovascular side affects of long term diabetes?
Myocardial infarction risk
Risk of stroke
Poor circulation to the periphery, particularly feet
What are the micro vascular complications that can arise from long term diabetes?
Diabetic eye disease
Diabetic kidney disease - nephropathy
Diabetic neuropathy
Diabetic foot
Why are diabetics more likely to get infections of the urinary tract?
Because high levels of glucose allow bacteria to thrive.
Gangrene is an example of a microvascular side affect of long term diabetes. Why are feet so susceptible to disease in diabetics?
Damage occurs to peripheral nerves causing loss of sensation.
Poor blood supply due to the high blood glucose which can lead to atheroschlerosis.
Increased chance of infection as high blood glucose provide ideal environment for bacteria to thrive.
What is a thalassemia?
A group of genetic disorders that leads to an imbalance between alpha and beta haemoglobin subunits.
Which form of thalassemia CAN’T form stable tetramer units? When do the symptoms appear?
Beta thalassemia. After birth.
What affect does a competitive inhibitor has on Vmax/Km?
Increase Km and ha no effect on Vmax
What affect does a non competitive inhibitor has on Vmax/Km?
No effect on Km, cause Vmax to decrease.
Outline the reasons for the referral of patients for karyotyping
Prenatal screening Birth defects Lab normally sexual development Infertility Recurrent fetal loss
Where does Hydroxylation of vitamin D take place?
Liver and Kidneys
What is the hormone that increase the rate of transcription of genes in cells and how does it do this?
Thyroid hormones- specifically T3. It enters the cell then binds to receptors in the nucleus. In the nucleus the hormone receptor complex binds to the DNA increasing the rate of transcription.
What are the enzymes required in glycogenesis?
Hexokinase, phosphoglucosmutase, glycogen synthase/branching enzyme
What is a good way of remembering which enzyme is required for the conversion of glucose-1-P to glucose-6-P of the reverse?
Mutase- like mutation, just a change
Phospho-contains phosphate
Gluco- contains glucose
Phosphoglucosmutase is the enzyme
What enzymes are requires for glycogenolysis?
Glycogen phosphorylase/de branching enzyme, phosphoglucosmutase, glucose-6-phosphatase.
Where are the 2 places glycogen is stored?
Liver and muscle
What stimulates glycogenolysis in the liver?
Glucagon
What stimulates glycogenolysis in muscle?
Adrenaline
What metabolic effect does growth hormone have and when is this important?
Increases lipolysis, important on the running of a marathon
Why is exercise so good for diabetics?
It can increase muscle sensitivity to insulin.
What is infection?
The multiplication/colonisation of a pathogenic microbe on or in a susceptible host with associated dysfunction or damage.
What is a good way of remembering which type of bacteria stains which colour is a gram stain?
Red-bad-negative-less-less peptidoglycan wall
So opposite is Positive is Purple. And it has a thick Peptidoglycan wall.
What type of stain is used to detect the causes of TB and leprosy?
Acid fast stain
What type of stain is used to stain bacteria? Explain why
Gram stain because they stain poorly with H&E
In what type of prokaryote would you find a capsid?
Virus
What type of pathogen/non pathogen would you find an envelope?
A virus
What is the difference between a pathogen and a non pathogen?
Pathogen - a bacterium/virus/other microorganism than can cause disease
Non-pathogen - a bacterium that doesn’t cause disease.
What are the three things required for something to be named an infection?
Must be shown to be present in every case of the disease
The agent mustn’t be found in cases of another disease
Once isolated to agent must be capable of reproducing the disease in experimental animals.
State 2 facts about mitochondria.
Maternally inherited
A bacteria
What are the 3 viruses which are DNA enveloped? What are their disease associations?
Hepatitis B- inflamed liver
Herpes - oral or genital
Small pox - small pox
Which are the 3 viruses which are RNA enveloped? What are their disease associations?
Rubella - rash
Rotavirus - diarrhoea
HIV - AIDS
Which is the DNA viruse which isn’t enveloped? What is the disease association?
HPV causes warts and cervical cancer
What are the two non enveloped RNa viruses?
Polio - inflammation of spinal cord
Hep A - liver disease.
Think here you have inflammation and liver disease but with hep B you have inflammation of the liver.
What are the gram positive / negative cocci?
Positive - streptococcus, staphylococcus
Negative - Neisseria
What are the gram positive / negative bacilli?
Positive - clostridium
negative - Salmonella, helicobacter, pseudomas, legionella
What is the role of rifampicin?
It prevents bacterial transcription by binding to RNA polymerase.
How does penicillin prevent bacterial cell wall synthesis?
It inhibits the transpepsidase enzyme. This enzymes forms cross links in the cell wall. Without these cross links the cell bursts.
What is tetrahydrofolate essential for? Where have you come across it?
DNA synthesis.
Methotrexate competitively inhibits DHFR, preventing the synthesis of DNA a. This is important in cancer therapy.
It is an example of a folate
What is the role of tetracycline? How does it do this?
It prevents bacterial protein synthesis by binding to part of a ribosome, preventing tarns from binding.
Where does glycogenolysis take place? When?
Liver - stress or fasting
Muscle - exercise
What enzymes is required for the conversion between glucose 1 phosphate and glucose 6 phosphate?
Phosphoglucosmutase
For the conversion of glucose 6 phosphate to glucose what enzyme is required? What’s produced and when does this take place?
Glucose 6 phosphatase, inorganic phosphate is given off and this takes place during gluconeogenesis.