Phase One Flashcards
1
Q
What are Hemidesmosomes, focal adhesions, Adheren junctions and desmosomes connect?
A
1) Hemidesmosomes join intermediate filament of cells to ECM
2) Focal adhesions join microfilaments of cells to ECM
3) Adheren junctions join microfilaments of cells to other cell
4) Desmosomes join intermediate filaments of cells to other cells
2
Q
What is defective in Kartagener’s syndrome?
A
Microtubules: there is a mutation in dynein
3
Q
What organelle is defective in Vohwinkle syndrome?
A
GAP junctions: recessive 26
4
Q
What are the two layers of the Dermis?
A
The papillary layer is the upper layer composed of loose areolar connective tissue.
The reticular layer is the bottom layer with dense irregular connective tissue.
5
Q
What are the three layers of the basement membrane and what collagen does it have?
A
The three layers are the Lamina Lucida, lamina propria ad the lamina reticularis. There is type four collagen.
6
Q
What are the four phases of hair growth?
A
1) Anagen: this last 2-7 years and involves the hair cells multiplying and dividing.
2) Catagen: this lasts 2-3 weeks and involves the hair
follicle shrinking and detaching form the dermal papilla.
3) Telogen: 3 months: the metabolic activity is reduced
4) Exogen: the hair detaches
7
Q
What are the four main stages of deep wound healing?
A
1) Homeostasis
2) Inflammation
3) Proliferation
4) Tissue Remodelling
8
Q
What the four stages of proliferation, the third stage in deep wound healing?
A
1) Re-vascularisation: new blood vessels form
2) Re-epithelisation: keratinocytes migrate and divide
3) Granulation: fibroblasts ,at down temporary ECM
4) Contraction: myofibrils contract the size of wound
9
Q
Describe four types of phosphorylation
A
1) Phosphorylation: adding a phosphate group
2) Acetylation: adding a acetyl group
3) Farnelysation: adding a farnesyl group which targets protein to cytoplasmic phase
4) Ubiquitination: adding a ubiquitin chain which targets protein to degradation
10
Q
What pathway of degradation do the following proteins undergo: membrane proteins, defective proteins, extracellular proteins, key metabolic enzymes and pathogenic proteins?
A
1) Membrane proteins undergo lysosomal
2) Extracellular proteins undergo lysosomal
3) Pathogenic proteins undergo lysosomal
4) Key metabolic enzymes undergo Proteasomal
5) Defective proteins undergo Proteasomal
11
Q
Name two antibiotic classes that are cell wall agents
A
Glycopepties and penicillin.
12
Q
Name two antibiotic classes that are protien synthesis inhibitors.
A
Aminoglycosides and macrolides.
13
Q
What inhibits DNA gyrase?
A
Quinolones
14
Q
What inhibits DNA synthesis?
A
Trimethoprim
15
Q
What is the action of Vancomycin?
A
This is a glycopeptide and is involved in cell wall.
16
Q
What word describes bacteria that cant make their own food?
A
Heterotrophic
17
Q
What is the meaning of Fastidious?
A
Bacteria that die very quickly
18
Q
What is the meaning of facultative?
A
Bacteria that can adapt to conditions
19
Q
What is the meaning of Obligate?
A
Bacteria that need specific conditions
20
Q
How is a single negative strand of RNA used for mRNA
A
The negative strand is converted into a positive strand using viral polymerase.
21
Q
Give an example of a single DNA virus
A
Herpes
22
Q
Give an example of a double DNA virus
A
HPV, Hep B
23
Q
Give an example of a single positive RNA
A
Hep C
24
Q
Give an example of a negative single RNA
A
Influenza, rabies
25
Give an example of a retrovirus
HIV
26
Name to location is the lymph node where B cell, T cells and macrophages are.
B cells are in the germinal centres. T cells are in the paracortex. Macrophages, as well as plasma cells, are in the medulla.
27
How many lobes does a neutrophil have and what colour does it stain?
Neutrophils have a multi-lobed nucleus and stain lilac. A high count would indicate an acute infection.
28
How many lobes does a eosinophil have and what colour does it stain?
Eosinophils have a bi-lobed nucleus and stain a bright red using an acidic dye.
29
How many lobes does a eosinophil have and what colour does it stain?
Basophils have either a tri- or bi- lobed nucleus and stain deep purple.
30
What agranular leukocytes has a horse-shoe shaped nucleus?
Monocytes
31
Describe the pathway of Hemopoiesis
```
Multipotent Stem Cell
Myeloid Stem Cell
Proerythroblast
Basophilic erythroblast
Polychromatic erythroblast
Orthochromatic erythroblast (final nucleated stage)
Reticulocyte
Erythroblast
```
32
A hemocytoblast differentiates into a Myeloid and Lymphoid stem cell. Describe the fates of these two cells
A lymphoid cells will differentiation into a lymphoblast and eventually go into T cells, B cells of NK cells.
A myeloid stem cells will differentiate into a myeloblast and a monoblast. The myeloblast will forms eosinophils, neutrohils and basophils. the monoblast will form a monocyte and eventually a macrophage.
33
Describe the first stage of Haemostasis.
The first stage is vasoconstriction. There is collagen exposure due to the damaged vessel. There is endothelin release from the endothelial cells which causes the constriction. The constriction reduces the blood flow to the area This is a Transient process.
34
Describe the first part of the second stage of Platelet plug formation.
This phase is known as primary haemostasis. The platelets adhere to the negative collagen and become activated. vWF serves to cross link the platelets (binding onto the GpIB receptor) and the collagen.
The platelets become activated after adhesion and the change shape from round to 'sea urchin'. Activated platelets will secrete the content of their granules to attract more platelets.
When the platelet changes shape, there is the alteration of the GpIIb/IIIa receptor and this increases the affinity for fibrinogen to form a mesh.
35
Describe the second part of the Platelet plug formation.
This is the formation of the fibrin mesh work. Sub-endothelial cells release TF which binds with factor VII to cause thrombin formation, this creates a network. During shape change, phosphatidylserine will be released onto the outer surface and will cause calcium to bind. This allows a surface for clotting factors.
Activated proteins will also release thromboxane A2 and this causes increased platelet aggregation.
36
Describe the antithrombotic properties of endothelium.
- The endothelium serves as a barrier between the collagen and platelets
- Endothelial cells release prostaglandin I2, NO and ADP-ase to reduce aggregation
- Endothelial cells release thrombomodulin which binds to thrombin and caused the activation of Protien C and S. This prevents coagulation activation.
37
Describe the Intrinsic pathway of the coagulation pathway
This is activated by the presence of negative surfaces. Factor 12 is activated, then Factor 11, then factor 9. With the help of factor 8, factor 9 activated factor 10.
38
Describe the extrinsic pathway of the coagulation pathway
This pathway is activated by the damaged tissue releasing TF. TF binds with activated factor 7 to activate factor 10.
39
Describe the common pathway of the coagulation pathway.
Factor Ten is where the two pathways meet. Factor 10 and factor 5 caused prothrombin to form thrombin. This causes the conversion of fibrinogen into fibrin.
40
What factors does thrombin have a positive feedback on in the coagulation pathway?
Factor II, V and VIII
41
What factor of the coagulation pathway helps the cross-linking of fibrin?
Factor XIIIa
42
What coagulation factors is Antithrombin III and inhibitor of and what drugs can activate it?
Antithrombin III is an inhibitor of factor X and thrombin. Heparin and Low-molecular-weight heparin can activate this.
43
What causes the breakdown of the fibrin clot and what drugs can enhance this?
Plasminogen is converted into plasmin and this causes the breakdown of the clot. Streptokinase and tPA can help activate this.
44
What chemicals form gamma-Carboxyglutamic acid and what factors is this a component off?
Gamma-Carboxyglutamic is formed by glutamic acid, oxygen and carbon dioxide. This forms a component of factors II, V, IX and X.
45
Describe the mechanism of action of Warfarin
The conversion of glutamic acid, oxygen and carbon dioxide to Gamma-Carboxyglutamic requires vitamin K. Warfarin serves to inhibit vitamin K.
46
Describe the process of transcription.
DNA helicase will open up the helix by breaking the hydrogen bonds. The RNA polymerase will start to read and form a mRNA molecule and this leaves through the nuclear pore.
47
Describe the two ends of a mRNA molecule
The 3' end has a poly-A tail with many A bases. The 5' end have a methylated cap.
48
Describe the process of translation: initiation, elongation and termination.
Initiation: a small protien sub-unit will bind to the methylated cap and moves to the initiation site. A tRNA molecule with a complementary amino acid binds to the mRNA codon. The large subunit will the bind and form the P and A site. The P site is where the first amino acid is and the A site is where the second is.
Elongation: the tRNA molecule will continue to add amino acids along and the chain will grow.
Termination: Once a stop codon is reached, a release factor will bind and causes the termination.
49
Describe the colour-based triage system
Red: Immediate care required
Yellow: Observation required and medical care will be needed
Green: This can wait but attention will be needed
White: This can be dismissed.
Black: There is no survival.
50
Describe the differences between Endotoxin and Exotoxins.
Exotoxins: these are secrete by both gram negative and positive, however, mostly by positive. They are secreted during the lag phase of growth and are not pyrogenic. They are produced inside the cell.
Endotoxins: these are only produced by gram negative as they are a part of the outer cell wall. They are made of lipids/polysaccharides and are released during cell lysis. They are pyrogenic.
51
Describe the Prothrombin time test.
The patients blood is decalcified to prevent coagulation. The plasma is separated and TF and calcium chloride is added. The time is taken for the blood clot to form and this should be around 10-14 seconds. Prolonged time could indicate a deficiency in factor VII, X, V, prothrombin, fibrinogen, vitamin K or liver disease.
52
Describe the Activated partial thromboplastin time test.
This test measures the intrinsic and common pathway. The decalcified patients blood has calcium, kaolin (hydrated aluminium silicate) and cephalin added. Kaolin is an activator of factor XII and cephalin is a substrate for platelet phospholipid. The time is taken for the blood to clot and this is around 30-45 seconds. A pro-longed time would indicate a bleeding disorder or a liver disease.
53
What is the function of the zona pellucida?
This is a protective coating over the fertilized oocyte that prevents premature implantation.
54
What happens in day four on fertilization?
The cells maximize contact with each other and the Morula forms. This then enters the uterus.
55
What happens on day 5/7 of fertilization?
The blastocyst forms and this is the first sign of differentiation. The inner cell mass forms the embryo and the outer cell mass forms the trophoblast.
56
Describe week two of fertilization
The trophoblast is first to implant and differentiates into the cytothroblast and syncytophoblast.
The inner cell mass forms the bilaminar disc. This is formed of two discs: the epiblasts (ectoderm) and the hypoblasts (endoderm).
57
What is the epithelium difference of the ectoderm and the endoderm?
The ectoderm is high columnar and the endoderm is low cuboidal.
58
What layer is the yolk sac made of?
The yolk sac is made of the hypoblast (endoderm)
59
What germ layer is the nervous system derived from?
The ectoderm.
60
Name eight derivates of the ectoderm.
Hair, Nails, Tooth Enamel, Pituitary Gland, Adrenal Medulla, Nervous System, Eye lens, Eye Cornea, Pineal Glands, Epithelial lining of the Anus, Epithelial lining of the Mouth, Terminal male Urethra
61
Name eight derivatives of the mesoderm.
Skeletal muscle, connective tissue, adrenal cortex, adipose tissue, connective tissue, ligaments, tendons. spleen, parenchyma, dermis and notochord.
62
What germ layer is the spleen and Dermis derived from?
The mesoderm
63
Name eight derivatives of the endoderm.
The epithelia lining of the respiraoty system, digestive tract, urethra, urinary bladder and reproductive tract. The liver, pancreas, thymus, thyroid and parathyroid glands.
64
What mutation causes Li-Fraumeni Syndrome?
A mutation is the p53 gene which is a tumour suppressor.
65
What mutation causes Burkitt Lymphoma?
A mutation is the MyC gene. This is an oncogene and is located on chromosome 8.
66
What is the Philadelphia translation?
This is a bcr-abl translocation that is located on chromosome 9 and 22. This causes chronic myelogenous leukaemia.
67
What does anaplasia mean?
Poor cellular differentiation
68
What does metaplasia mean?
This is an abnormal change in the natural of the tissue.
69
What does dysplasia mean?
This means abnormal growth
70
CARCINOMA describes tumour in which area: epithelial or connective?
A carcinoma is a epithelial tumour. A connective tissue tumour is known as a sarcoma.
71
Name three locations where collagen I is located.
Collagen one is located in the dermis, in tendons and in ligaments.
72
Name the type of collagen in Hyaline cartilage.
Type Two.
73
Name four location where type three collagen can be found.
The liver, granulation tissue, bone marrow and lymphoid organs.
74
What kind of cartilage is found in the basement membrane?
Type Four
75
Name two locations where type V cartilage is found.
A basement membrane linker and the cornea.
76
What molecule synthesizes elastin and what arranges it?
Elastin is synthesized by fibroblasts and is assembled by fibrilin.
77
Name Five common Glycosaminoglycan's (GAGs) and their location.
- Hyaluronic acid: synovial fluid
- Chondroitin sulphate: cartilage
- Heparin
- Heparin Sulphate: basement membrane
- Keratin Sulphate: cartilage
78
Aggrecan is a common proteoglycan found in cartilage. What are the two GAGs that compose it?
Aggrecan is made of chondroitin sulphate and keratin sulphate.
79
Perlecan is a common proteoglycan found in the Basement membrane. What GAG composes it?
Heparin sulphate.
80
Syndecan is a common proteoglycan found in cartilage.
| What are the two GAGs that compose it?
Syndecan is made of chondroitin sulphate and heparin sulphate.
81
Decorin is a common proteoglycan found in connective tissue. What GAGs is it composed of?
Decorin is composed of chondroitin sulphate and dermatan sulphate.
82
Fibrilin, Fibronectin, Lamin, Entactin and tenascin are what kind of molecules? What are their functions?
These molecules are glycoproteins.
Fibrilin is a elastin organiser. Fibronectin is a BM linker. Laminin is a primary BM organiser. Entactin is a BM linker. Tenascin is a linker is connective tissue.
83
What is defective in Marfan syndrome?
Fibrillin-1.
84
Describe Hyaline cartilage.
Hyaline cartilage has a perichondrium except for articular cartilage. It is found in the nose, trachea, end of long bones and ribs. It has collagen type two. It functions to resist compression and is supportive.
85
Describe Fibrocartilage.
Fibrocartilage has thick collagen fibres and has no perichondrium. It is highly compressible and resits tension. It is found in intervertebral discs, meniscus and public symphysis.
86
Describe Elastic cartilage.
Elastic cartilage has a perichondrium and is predominantly elastin. It has a higher concentration of chondrocytes due to the higher demand for elastin. It is found in the ear and epiglottis. It is very flexible.
87
Describe the differences between synarthrosis, amphiarthrosis and diarthrosis.
- Synarthrosis: no movement
- Amphiarthrosis: some movement
- Diarthrosis: free movement
88
Describe Fibrous Joints
Fibrous joints are dense connective tissue. They have no joint capsule and have limited movement.
There are three kinds:
- Sutures: these are only in the skull and have short connecting fibres. They ossify to become synastoses.
- Syndesmosis: These have longer fibres and are only joined by ligaments.
- Gomphosis: These are 'peg in socket' joints and they are found in the roots of teeth.
89
Describe Cartilaginous Joints
These joints are linked by cartilage. There are two types:
- Synchonodroses (primary): these are found in the epiphysis and clavicle. This is separated by hyaline cartilage and are synarthrotic.
- Symphysis (secondary): these are separated by fibrocartilage and are more flexible. They are found in the intervertebral discs and are amphiarthrotic.
90
Name the four types of cell found in the CNS and give their function.
- Astrocytes: these are star-shaped cells involved in support, migration, energy and insulation. They are protoplasmic in grey matter and fibrous in white matter.
- Oligodendrocytes: these cells process the myelin sheath
- Microglia: these are phagocytic cells
- Ependymal cells: these secrete cerebrospinal fluid and are cuboidal
91
Name the two cells of the PNS
- Schwann cells: these produce the myelin sheath
| - Satellite cells: support for cell bodies
92
Is Grey matter unmyelinated or myelinated?
Unmyelinated.
93
Name and give the function of Cranial Nerve One
Olfactory: smell.
| This is sensory
94
Name and give the function of Cranial Nerve Two
Optic: Vision.
| This is sensory
95
Name and give the function of Cranial Nerve Three
Oculomotor: upward, medial, downward, up and in movements the eye.
This is motor
96
Name and give the function of Cranial Nerve Four
Trochlear: down and in movements of the eye
| This is motor
97
Name and give the function of Cranial Nerve Five
Trigeminal: touch forehead and cheek and clench teeth.
| This is sensory and motor.
98
Name and give the function of Cranial Nerve Six
Abducens: look side to side
| This is motor
99
Name and give the function of Cranial Nerve Seven
Facial: anterior 2/3rds of tongue and smile.
| This is sensory and motor.
100
Name and give the function of Cranial Nerve Eight
Vestibulocochlear: hearing and balance.
| This is sensory
101
Name and give the function of Cranial Nerve Nine
Glossopharyngeal: posterior 1/3 of tongue and speech
| This is sensory and motor
102
Name and give the function of Cranial Nerve Ten
Vagus: digestion, slow heart rate, defection
| This is sensory and motor
103
Name and give the function of Cranial Nerve Eleven
Spinal Accessory: shoulder shrug
| This is motor
104
Name and give the function of Cranial Nerve Twelve
Hypoglossal: tongue movement
| This is motor
105
Name the five types of adrenergic recepotrs (effectors of noradrenaline) and describe their functions.
- Alpha one: located on smooth muscle and cause contraction
- Alpha two: located at neuromuscular junction (inhibit acetylcholine released) and at smooth muscle (relaxation)
- Beta one: heart and cause increased rate and vasodilation
- Beta two: This is on smooth muscle and it causes vasodilation.
- Beta three: located on adipose tissue and enhances lipolysis.
106
Give Eight effects of the sympathetic response.
- Pupil dilation
- Mucous reduction
- Saliva reduction
- Heart rate increased
- Artery constriction
- Bronchiole relaxation
- Decreased motility of GI tract
- Kidney decreased urine
- Liver increases glucose
- Sphincter contraction in bladder
- Increased sweat production
107
Give Eight effects of the parasympathetic response
- Pupil constriction
- Mucous increased
- Saliva increased
- Heart rate decreased
- Artery dilation
- Bronchiole contraction
- Increased motility of GI tract
- Kidney increased urine
- Liver increases glycogen
- Sphincter relaxation in bladder
- There is no change in sweat production
108
Describe the three stages of the cough reflex
- Inspiratory phase: a big breath is taken in, the vocal cords open, the muscles stretch, the pressure increased
- Compression: the glottis opens, the pressure increases, the respiraoty muslce contract
- Expiratory: the glottis open, air is forced out due to the high pressure
109
Give the symptoms and definition of Asthma.
Asthma is chronic inflammation of the airway.
| The symptoms include wheezing, chest tightness, breathlessness and a cough (worse in the morning or late at night).
110
Describe the pathogenesis of Asthma
```
An allergen is inhaled and is engulfed by APC's and presented to Th2 cells. This causes induction of Th2 cells. Th2 cells will release IL-13, IL-4 and IL-5.
IL-4 will causes class switching on B cells from IgM to IgE. IgE will bind with the FCER1 receptor with its Fc part
IL-5 will recruit eosinophils and IL-13 wills help with class switching and mucous secretion
```
111
Describe the process when an asthmatic is re-exposed to an allergen.
The allergen will form a cross-bridge with the IgE on the mast cell. This causes mast-cell to form a rough border and to dregranulate and release histamine, protease, eosinophil chemotactic factor and neutrophil chemotactic factor. There is also the activation of Phospholipase A2 and this causes the arachidonic pathway to occur, leading to the formation of prostaglandins and leukotrienes. There is also the activation of genes for making cytokines.
This will cause bronchospasm, vasodilation, bronchoconstriction. Eosinophils will causes endothelial damage.
112
Describe the different types of inhalers used for asthma treatment
- reliever inhalers are blue
- preventer inhalers are brown
- combined inhalers are pink, yellow or purple
113
Describe the drug treatment for asthma
- inhaled beta-2 agonist
- add inhaled corticosteroid
- add LABA or increase corticosteroid
- increase corticosteroid
- add either leukotriene receptor or theophylline
- maintain high dose and add oral corticosteroid
114
Describe the mechanism of action of Beta-2-agonists
The drug binds to a beta-2 recepotrs. The GDP on the alpha unit gets exchanged for a GTP and this activates adenylyl cyclase, forming cAMP. This leads inactivation of myosin light chain kinase and a decrease in intracellular calcium. This causes decreased contraction and hence bronchodilation.
115
Give examples of short and long acting beta-2 agonist.
Short-acting: salbutamol, terbutaline
| Long-acting: salmeterol
116
Give the mechanism of action of Anticholinergic drugs
The drugs bind to the muscarinic recepotrs and prevents acetylcholine form binding and this prevents bronchoconstriction.
117
Give examples of short and long acting anticholinergic drugs
Short-acting: ipratropium bromide
| Long-acting: tiotropium bromide
118
Give the mechanism of action of Theophylline
This blocks phosphodiesterase, an enzyme response for cAMP breakdown
119
Give the mechanism of Montelukast (leukotriene receptor antagonist)
Blocks LTD4, therefore preventing muscle contraction
120
Give examples of inhaled and oral steroids
Inhaled: beclometasone, budesonide, fluticasone, mometasone
Oral: prednisone
121
Describe the diagnosis of Asthma
- Peak flow will increase with bronchodilator
- FEV1 will increase with bronchodilator
- curshmann spirals and charcot-leyden crystals present in mucous
122
Describe the four layers of the stomach
- Mucosa: epithelium, lamina propria, muscularis mucosa
- Submucosa: blood vessels
- Muscularis: oblique, circular, smooth (longitudinal)
- Serosa: connective tissue
123
What stomach cells release Gastrin?
G cells
124
What stomach cells release pepsinogen?
Chief cells
125
What stomach cells release HCL?
Parietal cells
126
What type of epithelium does the oesophagus have?
Stratified squamous epithelium
127
Maltase is a brush border enzyme. What does it break down?
Maltose into Glucose
128
Lactase is a brush border enzyme. What does it break down?
Lactose into Glucose and Galactose
129
Sucrase is a brush border enzyme. What does it break down?
Sucrose into Fructose and Glucose
130
Name the four lobes of the liver
Right, Left, Quadrate and Caudate
131
Trypsin and peptidase are enzymes in the pancreatic juice. What do they break down?
Protein
132
The rectum as two sphincters; which one is involuntary and voluntary and what nerves innervate them?
- Involuntary internal sphincter: hypogastric nerve
| - voluntary external sphincter: perineal branch
133
Where does protein digestion begin?
In the stomach - with pepsinogen being converted into pepsin in the presence of HCL
134
Name the three zymogens secreted by the pancreas that are involved in protein digestion
Trypsinogen, chymotrypsinogen and procarboxypeptidase
135
What enzyme present on the border of the intestine serves to activate Trypsinogen
Enterokinase. This coverts Trypsinogen to Trypsin. This then forms chymotrypsin and carboxypeptidase.
136
Dipeptides are brush border enzymes involved in protien digestion. What do they break down?
Dipeptides
137
Amino peptidases are brush border enzymes involved in protien digestion. What do they break down?
Hydrolyses amino end
138
What molecule are peptides co-transported with?
Hydrogen. Hydrogen is then pumped back in in exchange for sodium.
139
What type of bonds does amylose have?
alpha -1,4-glycosidic bonds
140
What type of bonds does amylopectin have?
alpha -1,4-glycosidic bonds and alpha -1,6-glycosidic bonds
141
Where does carbohydrate digestion begin and why is it very transient?
It begins in the stomach with mechanical breakdown and salivary alpha-amylase which breaks down alpha -1,4-glycosidic bonds. This enzyme is de-activated by the acidity of the stomach.
142
What to molecules is starch broken into?
Oligosaccharides and shorter polysaccharides
143
What two brush border enzymes are involved in the breakdown of starch? What is the final result?
- maltase: hydrolysis maltose
| - sucrose: alpha -1,4-glycosidic bonds and alpha -1,6-glycosidic bonds into Glucose
144
Describe how glucose is absorbed into the blood?
Sodium glucose linked transporters are located on the apical surface of enterocytes. Two sodium molecules enter for one glucose molecule. Glucose is absorbed into the blood through the Glut-2-transporter.
145
Chylomicron has the largest concentration of lipid in comparison to vLDL, LDL and HDL True or False?
True.
146
What is the first enzyme involved in fat digestion?
Lingual lipase
147
What is the function of bile salts?
Emulsify lipids into small droplets and coat them to prevent reassembly.
148
Describe the process of fat being absorbed into the blood stream.
Micelles move to the brush border and the products leave into the cell. The products are synthesized back into triglycerides and phospholipids. They join with proteins and cholesterol to from chylomicrons. Chylomicrons at secreted back into the central lacteals an drain into venous blood at the thoracic duct..
149
What is intrinsic factor?
Molecules secreted by parietal cells that is involved in vitamin B12 absorption.
150
Name the tow functions of the pancreas.
Endocrine: insulin, glucagon
Exocrine: pancreatic juice
151
What is the first enzyme in glycolysis?
Hexokinase
152
How many molecules of NADH are formed in Glycolysis?
Two
153
What is the final product in Glycolysis?
Pyruvate
154
What is the first molecule that pyruvate is converted into in the Krebs cycle?
Acetyl-CoA
155
How many molecules of NADH are formed in the Krebs Cycle?
Six.
156
How many molecules of FADH2 are formed in Krebs cycle?
Two.
157
What molecule does pyruvate combine with to form citrate?
Oxaloacetate
158
How does acyl-CoA (formed from fatty acids) get transported across the membrane?
Carnitine
159
Where does the electron transport chain occur?
The mitochondrial inner membrane
160
Describe the blood supply to the kidney
Renal artery - Segmental artery - interlobar artery - arcuate artery- interlobular- afferent
161
What level are the kidneys located?
T12-L3
162
Does cortical nephrons have long or short Loop of Henle's?
Short. Juxtamedullary have long.
163
What cells in the Juxtaglomerular apparatus secret renin?
Granular cells
164
What cells in the Juxtaglomerular apparatus detect NaCl concentration
Macula Densa cells
165
Mesangial cells are located in the glomerulus. Are they capable of contraction?
Yes.
166
Describe the first step in blood filtration
This occurs in the glomerulus (within the Bowman's capsule). There is ultrafiltration of the blood has the podocytes only let small molecules through (<67kD). There should be no large proteins (Albumin) or RBCs.
167
Name Four molecules that are reabsorbed into the Proximal tubule.
- 100% glucose
- 100% amino acids
- 65% sodium
- potassium
- 65% water
- 90% bicarbonate
168
What is the function of the loop of Henle?
Concentration of urine.
169
Where in the loop of Henle is there 25% reabsorption of sodium?
Thick ascending tubule
170
Where in the loop of Henle is there a large amount of water reabsorption?
Thin descending loop.
171
Describe the counter-current recycling mechanism of the Loop of Henle.
There is active pumping of solutes in the thick ascending loop that diffuse back into the descending tubule.
172
Name two things secreted in the Distal convoluted tubule
Hydrogen and Potassium.
173
Does constriction of the afferent arterioles decreases GFR?
Yes. Dilation will increase GFR.
174
Describe the effect of increase blood pressure on the GFR.
- the stretch recepotrs n the afferent arterioles are activated
- elevated stretching causes smooth muscles depolarization
- smooth muslce undergoes contraction
- this decreases blood flow and hence GFR decreases
This process is Myogenic.
175
Describe the tubuloglomerular process when there is an increase in sodium, chlorine or water.
- the high concentrations are detected by macular dense cells
- the cells inhibit NO release
- NO usually causes vasodilation and hence a decrease causes constriction
- there is reduced blood flow and GFR decreases
176
Describe the Renin-Angiotensin-Aldosterone-System
- Juxtaglomerular cell secret renin in response to lowered blood pressure
- Renin cleaves amino acids from angiotensinogen (produced in liver) to from angiotensin 1
- angiotensin converting factor (produced in lungs) cleaves more amino acids and forms angiotensin II
- Angiotensin II causes vasoconstriction of systemic arteriole and efferent. Because efferent constriction is more, the GFR increases,
177
Where is Atrial Natriuretic peptide secreted?
The atria of the heart
178
What is the effect of ANP?
ANP is secreted in response to an increase in blood volume. ANP has many effects:
- dilates afferent arterioles
- increases blood flow to vasa recta
- inhibits sodium and water reabsorption in the PCT and CD
- prevents renin release
179
Where is ADH (Antidiuretic hormone) produced and secreted ?
ADH is made in the hypothalamus and secreted in the Posterior Pituarity Gland
180
Describe the action of ADH on the kidneys.
ADH is secreted in response to low water and it increases the permeability of the principle cells.
The hormones inserts more aqua-porin 2 channels into apical membrane on the collecting duct. This allows more water to be reabsorbed.
181
Give eight requirements for a screening programme
- Condition should be a important health problem
- There should be an accepted treatment available
- There should be facilities for diagnosis and treatment available
- Suitable test and examination
- Test acceptable to population
- Natural history and development understood
- Agreed policy on whom to treat
- Case finding is a continuous process
- Finically beneficial
- Identify disease in individuals wit no signs of symptoms
182
What is the age for cervical screening?
25-50: 3 years
| 50-65: 5 years
183
What is the age for Breast cancer screening?
50-70
184
What is the age for Bowel cancer screening?
50-74 years
185
What is the meaning of affinity?
How well a drug binds to a receptor
186
What is the meaning of efficacy?
The ability of a bound drug to produce an effect
187
Where in the urinary system is the M3 receptor located, what nerve innervates it and what is the effect?
The M3 receptor is located in the bladder and the pelvic nerve innervates it. The nerve realises acetylcholine to cause contraction. This is parasympathetic and when it is activated, it causes urination. This is involuntary.
188
Where in the urinary system is the Beta-3 receptor located, what nerve innervates it and what is the effect?
The Beta-3 receptor is located on the bladder. The hypogastric (sympathetic) nerve innervates it. The nerve releases noradrenaline and causes detrusor muscle relaxation. This causes urine retention.
189
Where in the urinary system is the alpha-one receptor located, what nerve innervates it and what is the effect?
The alpha-one receptor is located on the internal sphincter. It is innervated by the hypogastric nerve and is involuntary. The nerve releases noradrenaline and cause contraction of the sphincter. Hence this causes urine retention.
190
Where in the urinary system is the nicotinic receptor located, what nerve innervates it and what is the effect?
The nicotinic receptor is located on the external sphincter and is innervated by the pudendal nerve. This nerve arises from the somatic region. The nerve releases acetylcholine, causing contraction and allowing us to hold in our urine.
191
Explain what happens when there is an empty bladder.
There is less stretching in the bladder and the sensory pelvic nerve only sends out slow impulses to the sacral region. This stimulates the hypogastric nerve and causes relaxation of the detrusor muslce and contraction of the internal sphincter. The pelvic nerve is inhibited. The pudendal nerves are also stimulated so any urine can be held in.
192
Explain what happens when there is a Full bladder.
Increased urine will cause more stretching of the detrusor. This will cause the pelvic nerve to increase the rate of fast-firing neurons to the sacral region. The signals go to the Pons and has many effects:
- inhibition of the sympathetic nerve (relaxation of internal sphincter and no relaxation of detrusor)
- pelvic nerves are stimulated (detrusor contraction)
- inhibition of the pudendal nerve (no external sphincter contraction)
193
Due to the size difference between the tympanic membrane and the oval window, how much is sound magnified?
x22
194
What affect does the vibration of the stapes have?
The stapes is connected to the oval window and this causes the perilymph to vibrate. This causes the tectorial membrane to vibrate and this is transmitted to the basilar membrane.
195
Explain the process of vibration on the Hair cells.
when they move, they cause depolarization. Potassium channel open and the high potassium concentration causes calcium to form a neurotransmitter.
196
Describe the process of a Fever occurring.
- Toll-like recepotrs recognise exogenous pyrogens
- Immune cells releases endogenous pyrogens (IL-1 and TNF)
- These cytokines activate the phospholipase A2 and increase the COX pathway
- PGE2, in the hypothalamus, will stimulate neurotransmitter production and the reset the body temperature at an elevated level
197
Describe the Arachidonic Pathway
- The phospholipid membrane is converted into arachidonic by the phospholipase A2
The arachidonic acid then has two outcomes:
- Cyclooxygenase converts it into prostaglandin H2 and then into thromboxane and prostaglandins-
- Lipoxygenase converts it into leukotriene A2 and then into leukotriene B4 and leukotriene C4/D4/E4
198
What hair cells acts as a cochlear amplifier?
Outer hail cells
199
Name the antibiotic used for treating Otitis media
Amoxicillin
200
Describe some symptoms of Otitis Media
- Ear pain
- Tugging on ear
- Fever
- Irritability
- Difficultly feeding/sleeping
- Vomiting/diarrhoea
201
Describe the pathology of Otitis media
The Eustachian tube becomes blocked and fluid accumulates in the middle ear. The middle ear becomes inflamed and pus builds up. The ossicles can't vibrate easily.
202
What enzyme does Paracetamol block?
Cox-3
203
Which part of the antibody interacts with the immune cells and which part interacts with the antigen?
The Fc region interacts with the immune cells and the antigen interacts with the Fab region.
204
Describe IgG
- this makes up 80% of antibodies
- there is resistance to viruses, bacteria and toxins
- monomer
205
Describe IgE
- monomer
| - attaches to basophils and mast cells
206
Describe IgD
- one B cell surface
- monomer
- sensitization of B cell
207
Describe IgA
- glandular secretions: mucous, tears, saliva
- dimer
- attack of pathogens before entry into internal tissues
208
Describe IgM
- first calls of antibody to be made
- concentration decreases as IgG increases
- pentamer
209
What is the first antibody made?
IgM
210
Where do monocytes come from?
Myeloid progenitors
211
Which cells do MHC class one and two bind to?
Infected phagocytes will bind to CD8 cells via MHC-1. Uninfected phagocytes will bind to CD4 cells.
212
What part of the antibody determines what class it is?
The constant region
213
What part of the antibody recognise the epitope?
The variable region
214
What is the function of oil staining?
To refract light
215
Which part of the eye focuses light onto the retina?
The lens
216
What are the two parts of the vertebrae body?
Annulus fibrosis and Nucleus pulposes
217
What does the Lambdoid suture separate?
The parietal and occipital bones.
218
What two embryological remnants make the Forebrain?
Telencephalon and Diencephalon
219
What embryological remnant makes the Midbrain?
Mesencephalon
220
What two embryological remnants make the Hindbrain?
Metencephalon and Myelencephalon
221
What two eye muscles are not supplied by the Oculomotor nerve?
LR6SO4
- The lateral rectus is supplied by the Abducens
- The Superior oblique is supplied by the trochlear
222
What transcription factor is bound to RB?
E2F
223
What condition is a result of a P53 mutation?
Li-Fraumeni Syndrome
224
What two substances are not part of the ECM ground substance?
Collagen and Elastin
225
What part of the ear is for determining pitch?
Basilar membrane
226
What part of the eye is responsible for regulating amount of light?
The Iris
227
Describe the process of G-Protein signalling
When a ligand binds, the GDP bound the alpha subunit gets exchanged for GTP. The activated alpha subunit will dissociate from the beta-gamma unit.
228
Describe the formation of cAMP
Adenylyl cyclase, a membrane bound protien, is activated by the active alpha-GTP subunit. This converts ATP to cAMP.
In most cases cAMP will activate PKA.
In its inactive form, PKA will have two catalytic subunits and two regulatory subunits. cAMP binding causes the catalytic subunits to dissociate and cause phosphorylation of other molecules.
229
Where is the epigastric region located?
Top Middle
230
Where is the hypochondrium region located?
Top Left and Right
231
Where is the hypogastric region located?
Bottom Middle
232
What is the mechanism of the antibiotic Vancomycin?
This is a glycopeptie. This is a cell wall agents.
233
What is the mechanism of the action trimethoprim?
This is a metabolic action and DNA synthase.
234
How is a single strand of negative RNA transcribed into a positive strand ?
Viral polymerase
235
Which post-translational modifications targets proteins to go to the cytoplasmic face of the plasma membrane?
Farnelysation
236
Plasma is the yellowish fluid part of blood. Which blood plasma protein is involved in the maintenance of oncotic pressure?
Albumin
237
What are the products of the hydrolysis of lactose?
Glucose and Galactose
238
Which spinous process is the landmark for the inferior angle of the scapula?
T7
239
Which spinous process is the landmark for the spine of the scapula?
T3
240
What do macrolides target?
Protien synthesis
241
The digestive system border between the duodenum and jejunum is referred to as what?
Duodenojenenual flexure
242
What are the three main stages in phagocytosis?
1) recognition and attachment
2) engulfment
3) killing and degradation
243
What are the two main phagocytes of the body?
Neutrophils and Macrophages
244
What are the three main recepotrs on phagocytes?
- Mannose recepotrs
- Scavenger recepotrs
- Receptors for opsonins
245
What will mannose recepotrs on phagocytes bind to?
Glycoprotein and glycolipids on microbial cell walls
246
What will scavenger recepotrs on phagocytes bind to?
Microbes and oxidised/acetylated LDL
247
What is the role if opsonins and what are some examples?
The role is the establish a bond between microbes and phagocytes. Examples include IgG, C3b breakdown products, mannan-binding lectins
248
Explain the process of engulfment
There is membrane remodelling, cytoskeletal changes and actin polymerisation which results in pseudopods surrounding the microbe and bringing it inside. This forms a vesicle around the microbe and will form a phagosome. The phagosome will bind to a lysosome and form a phagolyosome.
249
What cell in the CNS forms the blood-brain barrier?
Astrocytes
250
How does polio enter the body?
GI tract
251
How does adenovirus type 8 enter the body?
Through conjunctiva
252
How does Hep B enter the body?
Inoculation
253
How many spinal nerves are there?
31 spinal nerves: 8C, 12T, 5L, 5S, 1C
254
How many spinal vertebrae are there?
33 spinal vertebrae: 7C, 12T, 5L, 5S, 4C
255
The Red Man Syndrome is a side effect caused by which antibiotic?
Vancomycin
256
describe the TMN scoring of malignant tumours
Stage Definition
T1 Tumour invading submucosa
T2 Tumour invading muscularis propria
T3 Tumour invading beyond muscularis propria
T4 Tumour involving peritoneum or directly invading other organs
257
Where is the cardiac notch found?
Anterior surface of the left lung
258
Where are cardiac impressions found?
Mediastinal surfaces of both the right and the left lung
259
What pathway do proteins destined for the lysosomes follow?
Proteins destined for the lysosome follow a variation of the secretory pathway in which the protein passes through the ER and Golgi.
Proteins destined for the nucleus, cytosol, mitochondria or peroxisome follow the cytosolic pathway as they do not go to the ER or Golgi.
260
Primitive streak is a linear band resulting from proliferation and migration of epiblast cells to which plane of the embryonic disk?
Dorsal-median
