Book 1

Question 1

What are the functions of the 3 main structures of the brain??

Answer 1

Cerebrum - higher function skills, like speech, higher intellectual function and fine control of movement
Cerebellum- balance and co ordination
Brain stem- autonomic processes, control of bp, blood volume, heart rate, respiration, arousal

Question 2

What two hemispheres are the cerebrum divided into?? How do they communicate?

What 4 lobes are there of the cerebral cortex??

Answer 2

Left cerebral hemisphere and right cerebral hemisphere, communicate via corpus callosum

Temporal- speech, lanugae, hearing, smell
Occipital- passt visual experience and vision
Parietal - sensory
Frontal- motor, emotions, personality

Question 3

What is the cerebral cortex for??

Answer 3

Concious thought and perception

Outermost 20mm of cerebral hemispheres

Question 4

What is the sensory and motor cortex?

Answer 4

Sensory - parietal lobe. Sensory neurons from sensory organs like ears, eyes, arrive at sensory cortex

Motor - in frontal lobe responsible for planning, control and voluntary movement. gets info from cerebellum. And messages sent via motor neurons to initiate voluntary movement

Question 5

What are the 3 parts of the brain stem and their functions?

Answer 5

Midbrain - upper part containing auditory and visual reflex centres, and contains cranial reflect activities like blinking and ducking head
Pons- middle part relays info between cerebrum and cerebellum. Helps coordinate breathing with medulla oblongata
Medulla oblongata - respiratory, vasomotor centre and cardiac centre for controlling breathing and cardiovascular system, also reflex systems like vomiting and swalloing

Question 6

What are the meninges, blood brain barrier and cerebrospinal fluid csf

Answer 6

Meninges- membranes around cns for protection. Outter dura mater- strong thick. Arachnoid mater- transparent thin pia mater - delicate inner layer

Blood brain barrier - tight junctions between capillaries and astrocytes . Foot processes which encircle capillaries and create semi permeable layer separating blood from neurones in brain.

Cerebrospinal fluid- fluid made from ependymal cells in canal of spinal cord. Transparent fluid containing urea, protein, glucose, lactic acid. Contributes to intra cranial pressure, supports the weight of cranium, allows exchange of substances by medium, keeps structures moist, protection

Question 7

What organ systems involved in intake of nutrients, oxygen and removal lf waste products

Answer 7

Oxygen- muscular system, nervous system and respiratory system
Nuritients - digestive system, muscular, endocrine, nervous

Removal of waste products - renal, urinary, respiratory system

Question 8

Functions of cell membrane?!

Answer 8

Encloses cell contents
Barrier
Communication
Cell movement 
Chemical reactions
Celluar identity

Question 9

Two types of endocytosis

Answer 9

Phagocytosis

Pinocytosis - cell drinking, vesicles allow small droplets inside the cell

Question 10

How do hormones produce changes in target cells?

Answer 10

Changes in permeability of cell membrane, activation or deactivation of enzymes, stimulation of cell division, stimulation of synthesis of proteins or regulatory molecules

Question 11

What 3 ways are endocrine cells, tissues and organs controlles

Answer 11

Neural, ions and hormonal (pituitary gland or hypothalamus)

Question 12

Definition of homeostatis ?

Answer 12

Keeping the levels of interal environment eithin narrow defined limits regardless of what enters the body or how the external environment differs, by autocorrective self adjusting mechanisms.

Comtrolloed by neural and hormonal systems

Negative feedback reverses any shift away from optimum state, automatic response involving a corrective mechanism,

Question 13

Effects of the sympathetic nervous system, part of the autonomic nervous system in PNS

Answer 13

Pupils dilate, promotes ejaculation, bronchi relax, increased breathing rate, rate increases in heart, noadrenaline adrenaline produced. Gi tract inhibited.
Skeletal muscle vaso dilation

Question 14

Example of the antagonisitic relationship of para and sympathetic responses?

How does this effect meds to give

Answer 14

The heart
Para - neurones release chemical acetyl choline
Sympathetic- neurone release noradrenaline or adrenaline on target tissue
Meds- if panicky give acetyl choline meds to activate para. Or meds to block action or adrenaline (prazosin)

Question 15

What is REM and non REM sleep?

Answer 15

REM- rapid eye movement, associated with dreaming and skeletal muscles are paralysed. Occurs 80-100 minutes after start of sleep. And then every 90 momutes, lastig 5-30 minutes each cycle. Rapid movement of eyes, and the heart and respiratory rate is irregular. 4-5 cycles a night of rem. If woken up during rem dreams are remembered.

Non REM- 4 stages of sleep, most of our sleep at night, reduction of physiological activity, and brain waves measured by ecg slower, and breathing and heart rate decrease.

Question 16

What is circadian rhythms??

Answer 16

Bodily changes in 24 hours. The normal fluctuations of the body like hormone secretion, temperatures and other physiological factors.
Can be effected by to a certain extent by external factors like meal times and work patterns.
Changes occur with regular increases and decreases of cellular activities that occur in 24 hours.

Question 17

What is the pineal gland what does it do?

Serotonin / melatonin

Answer 17

Pineal gland indirectly responds to light.
Suprachiasmatic nucleus is the biological clock and influences pineal gland.

Together they control secretion of hormone melatonin from pineal gland. Darkness stimulates melatonin, light inhibits melatonin.

Melatonin is made from serotonin, both from the amino acid tryptophan, rich in foods like milk, chocolate. Serotonin is associatied with feeling good and relaxation, and melotonin is sleepiness and secreted at night.

Question 18

Why do we need sleep?

Answer 18

Restoration - rest and repair
Energy conservation - save calories
Brain processing - synaptic processing

Question 19

What is erythropoiesis?

Answer 19

Formation of new red blood cells from red bone marrow. When dead or lost. As they grow they exclude their nucleus as they fill with haemoglobin. Squeeze in to red reticulocytes to begin circulating around the body.

When less oxygen levels hypoxia. Kidney (receptor) then releases erythropoietin which stimulates red bone marrow (effector) to make erythropoietin (controller) which increases rbc count, increases 02 carrying ability of blood

Question 20

What is plasma and the functions of plasma proteins??

Answer 20

Steaw coloured sticky fluid made of 91% water and 7% plasma proteins of albumins, a globulins, y globulins and beta globulins
Functions are
Clotting blood
Antibodies are y globulins
Transport substances are carried in blood eg calcium by albumins
Plasma proteins contribute to viscosity of blood helping with resistance in blood vessels increasing bp

Question 21

What is haemostasis and what are the 3 stages??

Answer 21

Haemostasis is the stemming of blood following damage to the blood vessel.

Vascular spasm
Formation of a temporary platelet plug formation
Co agulation

Question 22

What is vascular spasm in heamostasis?

Answer 22

Vascular spasm is when the smooth muscle fibres contract in the damages walls of blood vessels. Reducing blood flow to damage. Mimmediate protection

Question 23

What is platelet plug formation in haemostasis?

Answer 23

Im a damaged blood vessel, collagen fibres are exposed to blood. Platelets stick to the collagen causing a platelet plug which blocks minor bleeding,
Thromboxane makes platelets sticky allowing the plug to form

Question 24

What is the co agulation phase of haemostasis?

Answer 24

Last but most effective method,
Goal is to convert fibrinogen to fibrin,which then entraps platelets and blood cells and seal the cut. Requires clotting factors that was normally in active.
Substances released from damaged tissues results in prothrombin activator, which activates coagulation.
This causes prothrombin to be converted to thrombin, with calcium present
Thrombin convets soluble fibrinogen to insoluble firbin
Fibrin forms a network of threads which traps platelets and blood cells to form a clot halting bleeding.
Calcium always needs to be present

Question 25

What is firbinolysis?

Answer 25

Process that breaks down the fibrin clot by firbinolytic agents

Question 26

What are anti-platelet drugs?? In haemotology

Answer 26

They reduce the risk of clots forming in the blood. Reducing stokes and heart attacks. Aspirin is an anti platelet drug as it prevents the formation of thromboxane by binding to an exxyme cyclooxegenase (cox) which prevents platelets being able to stick together.

Question 27

What are anticoagulant? In haemotology like antiplatelet drugs

Answer 27

Anti coagulant drugs reduce ability of blood to clot. Like heparin (what mast cells make) and warfarin which interferes with the action of vitamin K it is a coenzyme of prothrombin

Question 28

What cofactor is needed in the liver as a clotting factor to produce prothrombin??

Answer 28

Vitamin K | Deficiency leads to bleeding,

Question 29

What are the cells in muscle tissue and what are their characteristics??

Answer 29

Cardiomyocytes Lots of mitochondria, need calcium for contraction Striated mononucleated Y shaped Joined by intercalated discs which contain gap junctions which allows ions to move from cell to cell allowing depolarisation,

Question 30

What are the 3 stages in cardiac cycle?

Answer 30

Atrial systole - contraction of the atrium after SA node depolarises it Ventricular systole- ventricular contraction after AV node depolarises it Complete diastole - relaxation of heart where blood is passively filling from atrium in to ventricles (passive ventricular filling)

Question 31

What dos ECG stand for? And what does it all show?? What is sinus rhythm?

Answer 31

Electrocardiogram Sinus rhythm is the natural rhythm of the heart, P wave- depolarisation of atrium QRS- depolarisation of ventricles T - repolarisation of ventricles before diastole

Question 32

What is digoxin?

Answer 32

Glycoside from foxglove plant,used to treat heart problems like atrial fibrillation, effects like able to slow down heart, and help it beat more regularly by distributing concentration of ions in cardiomyocytes and reduces conductivity in av node.

Question 33

What is blood pressure and what 3factors effect it?

Answer 33

Blood pressure is the force exerted by blood on the inner walls of blood vessels. Heart rate, blood volume and viscosity, blood vessels in relation to their diameter

Question 34

What is the equation to calculate blood pressure?

Answer 34

Blood pressure = cardiac output x total peripheral resistance

Question 35

What is the equation to find out cardiac output?

Answer 35

Co = stoke volume x heart rate Total volume of blood pumped out of ventricles during a minute Stroke volume is volume ejected from left ventricle per 1 contraction

Question 36

What is peripheral resistance?

Answer 36

Peripheral resistance is the resistance to blood flow which is mainly created by the diameter of blood vessels Controlled by short term nervous system and long term hormones

Question 37

How can heart rate be controlled?

Answer 37

Baroreceptors (receptor) in aortic arch and internal carotid arteries. Send info to cardiac centre in medulla (in brain stem which is the controller) which is controlled by autonomic PNS parasympathetic and sympathetic nervous systems, heart is the effector by neurones exciting the SA node, AV node and cardiac muscle, increasing heart rate in sympathetic.

Question 38

How is peripheral resistance regulated?

Answer 38

Baroreceptors in aprtic arch and internal carotid ateries detect lower blood pressure, nerve impulses sent to neurones in the medulla in the vasomotor centre. Which is the controller of the diameter of arterioles. Vasomotor tone in blood vessels is controlled by vasomotor centre, and sympathetic impulses lead to vasoconstriction of smooth muscle. Increases peripheral resistance

Question 39

What are baroreceptors?

Answer 39

Pressure sensitive receptors which detect changes in the stretch in the artery walls due to blood pressure changes, which sends impulses to vasomotor centre and cardiac centre in medulla Found in aortic arch and internal carotid arteries

Question 40

What are antihypertensives? Pharmacology of heart rate

Answer 40

Class of medicines that help to control high blood pressure. Diuretics try and reduce volume of fluid, Beta - blockers work by blocking effect on adrenaline on the heart, decreasing heart rate and force of contraction Calcium channel blockers work by blocking the cardiomyocytes from having calcium for contraction. So will dilate blood vessels and reduce the force of contraction Some try to suppress sympathetic nervous system

Question 41

What is amygdala hijack and allostatic load?

Answer 41

Amygdala hijack occurs when a threat overwhelms the brain involving emotional distress, anger, impulse and fear taking actions which may later be regretted Allostatic load- chronic stress with repeated reactions from amygdala leads to wear and tear of the brain and body.

Question 42

What is the long term stress response? HPA axis (hypothalamic-pituitary-adrenal axis)

Answer 42

Danger detected by amygdala via eyes or ears Distress signals sent to hypothalamus who is in charge of the stress response stimulates sympathetic system, activating pituitary gland and adrenal gland Adrenal medulla in adrenal cortex produces adrenaline CRF is send to Pituitary gland from hypothalamus which makes the pit gland release ACTH ACTH activates the adrenal cortex to produce cortisol into blood which increases energy availability by increasing glucose and fatty acids in blood. Suppressed immune system and is an anti-inflammatory

Question 43

What 4 ways can the respiratory system by divided?

Answer 43

Upper respiratory tract- from nose is larynx Lower respiratory tract- trachea to alveoli Conduction zones- function of getting air in and out of lungs, warms and filters air. Eg nose pharynx, larynx, trachea, bronchi Respiratory zone- gas exchange at alveoli, alveolar duct

Question 44

Functions of respiratory system?

Answer 44

``` Filter, humidy and warm air Gas exchange Get air in and out of lungs Expel waste products Speech Smell ```

Question 45

What are the lungs like?

Answer 45

Two cone shaped organs protected by ribs, sternum and vertebrae. Divided into regions of lobes, left 2 right 3 lobes Protected by double layered protective membrane. Called the pleurae. One layer covering the lungs is visceral pleurae, and one covering walls of thorax is the parietal pleurae. Thin layer between there is pleural fluid

Question 46

What is the equation of respiration and what is internal respiration?

Answer 46

Glucose + oxygen = atp co2 and water C6h12o6 + 6o2 = 2900kj 6h2o 6co2 Internal respiration is the process where oxygen is unloaded by the tissue capillaries and taken up by tissue cells and the reverse happens with co2 External respiration - gaseous exchsange in lungs Pulmonary ventilation - action of breathing inspiration and expiration Co2 carried as carbonic acid in blood (co2 and h2o)

Question 47

What helps diffusionim alveoli

Answer 47

Large s a Thin permeable membrane over short distance High conc diff Extensive blood supply surrounding alveoli

Question 48

Describe the alveoli and linings of the airways

Answer 48

Sac like alveoli has 2 types of cells, simple squamous epithelial, thin, and cuboidal epithelial which secrete pulmonary surfactant, which is made from phospholipids and proteins, lowers surface tension allowing them to inflate after exhalation, and prevents them collapsing Alveolar gas exchange occurs From nose to larynx theres pseudostratified columnar, cilitated epithelial, Bronchioles have cuboidal epithelial with cilla, taking mucus to larynx. Goblet cells- mucus Larynx- epiglottis Trachea bronchi- c shaped cartilage rings

Question 49

The process of inspiration and expiration?

Answer 49

Inspiration is active , ribs move up and out, diaphragm curves down. Expiration is passive and relies on muscle relaxation and elastin recoil. Diaphragm relaxes and intercostal muscles relax. Down and in. Due to pressure and volume changes.

Question 50

Nerve supply of the muscles in respiration

Answer 50

Intercostal muscles- intercostal nerves | Diaphragm - phrenic nerves

Question 51

How is breathing respiration regulated?

Answer 51

Central chemoreceptors in the medulla respond to lowering of PH due to co2 increase in cerebrospinal fluid, which gets in through blood brain barrier. As a rise in Co2, lower the PH. Peripheral chemoreceptors in aorta and carotid bodies detect change in co2 and falls in o2 in blood. Both chemoreceptors Stimulate respiratory centre in medulla oblongata and pons, they increase depth and rate of breathing, which lowers co2 level.

Question 52

What happens in brain stem respiratory centre? Chemoreceptors to respiratory centre to lungs

Answer 52

Areas referred to as medullary rhythmicity area 1- dorsal respiratory group in medulla integrates chemoreceptor info and signals VRG 2 - ventral respiratory group in medulla is the basic rhythm generator 3- apneustic centre - in pons helps regulate depth and rate of inspiration 4- pneumotaxic respiratory group - involved in regulation of apneustic centre and medullary rhythmicity area

Question 53

What is lung compliance and lung surfactant?

Answer 53

Lung compliance is a measure of how easy it is to inflate the lungs due to elastic Surfactant- in alveoli allow the walls to be separated and stretch. Acts as a detergent in lowering surfactant tension. Increases lung compliance

Question 54

What 3 ways can airway resistance be increased b

Answer 54

Inflammation, mucus in excess, bronchi constriction

Question 55

What drugs can cause the respiratory system to be depressed?

Answer 55

Opoids, eg anthistamines may cause sneezing, congestion and mucus

Question 56

What are macronutrients??

Answer 56

Macronutrients are nutritional components that are required in large amounts and provide energy Carbs energy fats energy fatty acids proteins energy and growth and repair

Question 57

What are micronutrients ? | What are fat soluble and water soluble vitamins?

Answer 57

Dietary components required in small amounts like minerals and vitamins. Not produced in the body. Fat soluble vitamins (ADEK) Can be stored in liver Water soluble vitamins include vitamin B complex and vitamin C

Question 58

What are the function of fat soluble ( ADEK) | And water soluble (B C)

Answer 58

A- important roles in embroyonic development, organ formation, eye development D- absorption of calcium and healthy bones E- antioxidant which protects cell membrane helps to maintain healthy skin, eyes and strengthens immune system. K- synthesis of blood clotting proteins B complex- metabolism and energy production from carbohydrates fat and protein. Role in cell division and growth C- cofactor in enzyme controlled reactions, important for collagen synthesis and healthy connective tissue, helps wound heal

Question 59

Clinical manifestations of dehydration? 3 ways

Answer 59

Fall in blood pressure - reduction in cardiac output Fall in capillary refill time- rate at which blood refills capillaries is slower than norm. Less fluid in blood means the time it takes for pad to return to normal colour following release of pressure is longer. Reduction in skin turgor- lack of water in dermis so fold of skin will take longer to come back to normal position when pinched

Question 60

Identify the two sources the kidney gets blood from?

Answer 60

Receives 1.5 litres of blood every minute from hepatic portal vein from the gut, and hepatic artery

Question 61

Definition of digestion?

Answer 61

The process where large, complex substances are broken down in to small, simple substances that can be easily absorbed

Question 62

What two things is the digestive system made up of?

Answer 62

The digestive tract - stomach, intestines, rectum, mouth, oesophagus, Accessory organs - liver, pancreus, gall bladder, salivary glands

Question 63

What organ location in abdominal cavity??

Answer 63

Right upper-liver, pancreas, gall bladder, transverse colon Left upper- stomach, transverse colon, pancreas, spleen Right lower- ascending colon, small intestine Left lower- descending colon, small intestine, sigmoid colon

Question 64

What is ingestion,propulsion, elimination?

Answer 64

Ingestion- mouth Propulsion- movement by peristalsis, oesophagus, stomach, small i Elimination - anus and rectum

Question 65

What are the functions of saliva from salivary glands, and what enzyme is in saliva

Answer 65

Amylase enzyme that initiates starch digestion Saliva has an antibacterial effect as the enzyme lysozyme destroys bacteria Saliva washes away food that can be a source of bacteria Saliva acts as a buffer as it contains bicarbonate which neutralises acid preventing dental cavities

Question 66

What are the four layers of the gi tract wall lumen?

Answer 66

Mucosa Submucosa Muscularis Serosa

Question 67

What is a bolus? And process of swallowing?

Answer 67

A bolus is a ball of food formed during mastication, and directed around the mouth by the toungue until swallowed, where it moves from the mouth to the pharynx into the oesophagus. Epiglottis is important to prevent food entering trachea

Question 68

What is the inner lining of the gi tract called and its function?

Answer 68

Mucosa- inner layer made from epithelial tissue. Subjected to wear and tear as in direct contact with food. Its thick epithelial in places like the rectum, mouth

Question 69

The second layer of gi tract and its characteristic?

Answer 69

Sub mucosa - loose connective tissue contains nerves, blood and lymph vessel, blood supply enables nourishment of tissues and serves for transport products of digestion.

Question 70

What two things is the digestive system made up of?

Answer 70

The digestive tract - stomach, intestines, rectum, mouth, oesophagus, Accessory organs - liver, pancreus, gall bladder, salivary glands

Question 71

What organ location in abdominal cavity??

Answer 71

Right upper-liver, pancreas, gall bladder, transverse colon Left upper- stomach, transverse colon, pancreas, spleen Right lower- ascending colon, small intestine Left lower- descending colon, small intestine, sigmoid colon

Question 72

What is ingestion,propulsion, elimination?

Answer 72

Ingestion- mouth Propulsion- movement by peristalsis, oesophagus, stomach, small i Elimination - anus and rectum

Question 73

What is the inner lining of the gi tract called and its function?

Answer 73

Mucosa- inner layer made from epithelial tissue. Subjected to wear and tear as in direct contact with food. Its thick epithelial in places like the rectum, mouth

Question 74

What is a bolus? And process of swallowing?

Answer 74

A bolus is a ball of food formed during mastication, and directed around the mouth by the toungue until swallowed, where it moves from the mouth to the pharynx into the oesophagus. Epiglottis is important to prevent food entering trachea

Question 75

What are the four layers of the gi tract wall lumen?

Answer 75

Mucosa Submucosa Muscularis Serosa

Question 76

What are the functions of saliva from salivary glands, and what enzyme is in saliva

Answer 76

Amylase enzyme that initiates starch digestion Saliva has an antibacterial effect as the enzyme lysozyme destroys bacteria Saliva washes away food that can be a source of bacteria Saliva acts as a buffer as it contains bicarbonate which neutralises acid preventing dental cavities

Question 77

The second layer of gi tract and its characteristic?

Answer 77

Sub mucosa - loose connective tissue comtaines nevres, blood and lymph vessel, blood supply enables nourishment of tissues and serves for transport products of digestion.

Question 78

3rd and 4th layer of gi tract?

Answer 78

Muscularis- 2 layers of muscular layer smooth muscle. Circular and longitudinal muscle with nerves In-between.co ordinated contraction allows for peristalsis. In mouth, pharynx and upper part of oesophagus contains skeletal muscle involved in voluntary swallowing. Serosa- outer coat for protection. Loose fibrous tissue containing blood vessels, nerves and lymph vessels.

Question 79

What is the oesophagus and characteristics?

Answer 79

Connects the pharynx to the stomach. Mucus cells in mucosa allow to line airways. Circular and longitudinal muscle in muscularis layer allows for peristalsis for bolus Oesophagus has upward curve as it goes through diaphragm to prevent food going back into oesophagus once it has entered the stomach. Also there is a cadiac spincter which opens and closes to prevent reflux.

Question 80

What is the 3 parts of the stomach?

Answer 80

Fundus by the cardiac sphincter The body middle part Antrum lower part by the pyloric sphincter

Question 81

Characteristics of stomach?

Answer 81

Folds in mucosa and submucosa allow it to expand, also has gastric pits that secrete diff substances in to the stomach. Eg goblet cells mucus to coat lining of stomach G cells produce gastrin hormone for gastric juices Patietal cells produce hydrochloric acid and intrinsic factors for absorption of vit B Muscle longitudal and circular muscle in muscularis layer allows it to churn and mix the food with gastric juices producing chyme. Small amounts of chyme are squirted through the pyloric sphincter into small intestine

Question 82

Parts of the small intestine??

Answer 82

Duodenum - contains glands which secrete alkaline mucus which neutralises acidic chyme. Also large ducts from major accessory organs Jejunum- follow duodenum its 2.5 metres long Ileum - 3.5 metres long attached to large intestine at the ileocaecal sphincter Simple sugars, amino acids and fatty acids absorbed by diffusion and active transport.

Question 83

What happens at large intestine??

Answer 83

``` From ileocaecal valve to rectum prevents back flow to small i Absorption of water and electrolytes Storage and elimination of faeces Bacteria produce vitamins Bacteria digest some polysaccharides ``` No villi and food no longer in a chyme Mucus cells in mucosa layer to facilitate passage of faeces and protect the walls. Flatus is produced from bacterial fermentation of carbs

Question 84

What is the functions of the liver, and how this contributes to homeostasis?

Answer 84

Storage - iron, glycogen (glycogenesis) fat soluble vitamins (ADEK) Regulation, synthesis and secretion - bile, cholesterol, clotting factors (prothrombin) and plasma proteins Purification - red blood cells, transformation of drugs in to water soluble, and breakdown of amino acids into co2' water, energy and ammonia, but that is toxic so turns in to urea which is then transported to kidney to be eliminated Fighting infections - kupffer cells. That destroy any bacteria

Question 85

What is the liver made up from?

Answer 85

Liver lobules cylindrical 2mm diameter Hepatocytes which carry out metabolic functions Sinusoids Stellate cells involved in fibrosis and formation of scar tissue in response to liver damage Central vein in the centre of lobule, with cords of hepatocytes radiating out. In spaces between hepatocytes there are cells of sinusoids which are think walled blood vessels lined with epithelial and kupffer cells (macrophages which remove ages red blood cells, bacteria and debris) 3 vessels around the edge of each lobule, bile duct, hepatic portal vein and hepatic artery.

Question 86

Function of bile produced by kidney?

Answer 86

Emulsifies fat particles, large s a allows lipase enzymes secreted in pancreatic juice to digest lipids Waste products from haemoglobin, like bilirubin and excess cholesterol are excreted in bile.

Question 87

What is the composition of bile?

Answer 87

Water, mineral salts, mucus, bile salts, cholesterol

Question 88

What is the functions of the liver, and how this contributes to homeostasis?

Answer 88

Storage - iron, glycogen (glycogenesis) fat soluble vitamins (ADEK) Regulation, synthesis and secretion - bile, cholesterol, clotting factors (prothrombin) and plasma proteins Purification - red blood cells, transformation of drugs in to water soluble, and breakdown of amino acids into co2' water, energy and ammonia, but that is toxic so turns in to urea which is then transported to kidney to be eliminated Fighting infections - kupffer cells. That destroy any bacteria

Question 89

What is the liver made up from?

Answer 89

Liver lobules cylindrical 2mm diameter Hepatocytes which carry out metabolic functions Sinusoids Stellate cells involved in fibrosis and formation of scar tissue in response to liver damage Central vein in the centre of lobule, with cords of hepatocytes radiating out. In spaces between hepatocytes there are cells of sinusoids which are think walled blood vessels lined with epithelial and kupffer cells (macrophages which remove ages red blood cells, bacteria and debris) 3 vessels around the edge of each lobule, bile duct, hepatic portal vein and hepatic artery.

Question 90

Function of bile produced by kidney?

Answer 90

Emulsifies fat particles, large s a allows lipase enzymes secreted in pancreatic juice to digest lipids. Has bile salts made from cholesterol which act like detergents and break down the bile Waste products from haemoglobin, like bilirubin and excess cholesterol are excreted in bile.

Question 91

What is the composition of bile?

Answer 91

Water, mineral salts, mucus, bile salts, cholesterol

Question 92

What is the process in to the small intestine??

Answer 92

Bile is concentrated and stored in the gall bladder After a meal is eaten fatty acids in duodenum stimulate endocrine cells to release hormone cholecystokinin (CCK) CCK produced in the walls of duodenum stimulates the smooth muscle of the gall bladder to contract allowing bile to be released in to the duodenum

Question 93

Definition of a drug? | And define pharmacokinetics?

Answer 93

A drug is any substances used for treatment (antibiotics), relief, diagnosis (barium) or as a preventative of disease. (Warfarin) How the body deals with the drug

Question 94

What are the two types of administration?

Answer 94

Enteral refers to anything involving the gi tract from mouth to rectum, oral, rectal, Parenteral means to avoid the gut, any other method away from the gi tract eg injections, topical ,vaginal

Question 95

What are the 4 processes of pharmacokinetics?

Answer 95

Administration Distribution Metabolism Elimination

Question 96

What is drug absorption?

Answer 96

The process from administration through till the time it reaches the tissues and is available for use Maybe involve having to get in to circulation but not in cases of topical, inhalation. Drugs must be converted to soluble state through dissolution

Question 97

What factors effect drug absorption?

Answer 97

Drug prep - how quick it disintegrates, tablets, capsules Interactions - ph, stomach contents Physiological factors - individual factors as to how quick the drug moves through digestive system. Due to age, diarrhoea Administration route, dosage and drug

Question 98

What is distrubtion of drug and what is meant by unbound free drug?

Answer 98

Distribution is when drug absorbed in blood stream is distributed to its site of action Only unbound drug molcules and freely diffusible can diffuse out of capillaries in to tissues. This drug are carried in blood ina simple solution, - free drug Mot free drug are bound to plasma albumins so cant exert its effects The conc of bound drug depends on ph, presence of other drugs, conc of plasma proteins and drug

Question 99

What is drug metabolism?

Answer 99

Transforming the drug so it is more water soluble and can be excreted , at the liver mainly, or can be kidneys, lungs and plasma The liver attempts to break the drugs down in to parts so it can be eliminated. Metabolised in to inactive metabolites

Question 100

What is the first pass effect in the metabolism of drug in liver?

Answer 100

First pass effect is the effect liver metabolism has upon the drug during its first passage through the liver, and how much is inactive Determines the half life, amount of drug reaching general circulation and whether it undergoes bio transformation. Which is the conversion of molecules from one form to another within an organism

Question 101

What is bio transformation?

Answer 101

Conversion of molecules from one form to another within an organism. Pro drugs go from inactive to active during bio transformation

Question 102

What is excretion of drugs?)

Answer 102

Active or inactive drugs removal from site of action, by kidneys, skin, lungs, bladder , liver

Question 103

What is bioavailability?

Answer 103

The fraction of am administered dose of the drug that reaches the systemic circulation

Question 104

What is modified release drugs and its benefits?

Answer 104

Modified release preps are designed to slowly release drug into the gi tract over a period of time , Dose frequency is reduced Less peaks and troughs in plasma levels so more sustained therapeutic effect Peak plasma level is reduced so less side effects

Question 105

In what proteins do drugs exert their effects??

Answer 105

Receptors, enzymes, ions and carrier transport molecules

Question 106

What 4 ways do drugs tend to work??

Answer 106

Replace missing chemicals or act as their substitutes Stimulate particular cell activities Slow down or inhibit cell activities Interfere with the function of foreign cells

Question 107

What is a ligand?

Answer 107

Collective name for a chemical that binds to a receptor eg hormones, neurotransmitters

Question 108

What are the drugs that target receptors classified as??

Answer 108

Antagonists and agonists

Question 109

What is drug affinity ?

Answer 109

Interaction between the drug and the binding site, the closer the fit and greater number of bonds , the higher the affinity for the drug for the receptor

Question 110

What are agonists?

Answer 110

When The drug has the same effect on the receptor as the natural substance that normally binds to receptor. Can increase or decrease cell activity

Question 111

What is an antagonist? What are the two types?

Answer 111

``` When the bound drug blocks the binding sites of the natural substance and so prevent its effects. Get competitive (irreversible and reversible) and non competitive ```

Question 112

What two sorts of drugs work by enzyme??

Answer 112

NSAIDS - non steroidal anti inflammatory drugs , inhibit enzyme COX cyclooxygenase , responsible for making chemical mediators including prostaglandins, which play a key role in inflammation and pain Acteylcholinesterase inhibitors - Alzheimer's Acetylcholine is a neurotransmitter that improves memory , inhibit acetylcholinesterase enzyme that breaks down acetylcholine in synaptic cleft so more acetylcholine left for memory

Question 113

What drug is used as an example of how drugs affect transport carriers?

Answer 113

Selective serotonin re-uptake inhibitors (SSRI) which prevent re uptake of serotonin from synaptic cleft back in to ore synaptic cleft - so more chance of the serotonin receptor being activated - mood enhancement

Question 114

What examples of drugs that effect ion channels?

Answer 114

Calcium channel blocker - vasodilator reducing peripheral resistance Sodium channels for propagation of the action potential along axon Potassium channel - prolong repolarisation GABA -reduces excitability in the cns