cells to systems 1 Flashcards

(95 cards)

1
Q

four basic types of tissue

A

1) nervous tissue
2) connective tissue
3) muscle tissue
4) epithelial tissue

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2
Q

List the 10 body systems and whether generalised or localised

A

1) musculo-skeletal - G
2) cardiovascular - G
3) immune and lymphatic -G
4) endocrine - L
5) nervous - G
6) integumentary system -G
7) respiratory - L
8) digestive - L
9) renal - L
10) reproductive - L

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3
Q

what is a peroxisome

A

contain enzymes that detoxify certain toxins

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4
Q

what does the body consists of and what are the percentages

A
water (60%), 
protein (17%), 
lipids (15%), 
minerals (inorganic acids and electrolytes 5%), 
nucleic acids (2% ) 
carbohydrates (1%)
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5
Q

methods of examining tissues

A

1) fixation (e.g. formalin) - treatment with chemical that stops enzymatic activity, freezes the tissue at state of fixation
2) embedding (e.g. paraffin wax) - put into solid medium so can cut sections of tissues
3) sectioning (~ 5 μm thick) - cut with special scissors
4) staining, e.g. haematoxylin and eosin (H&E) - combination most commonly used stains nucleus and ribosomes - mRNA
5) mounting - put coverslip on it using mounting medium that is glow like substance that is clear and goes hard so get permanent preparation

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6
Q

cells when end in -blast and -cyte what does it mean

A
  • blast - not a fully differentiated cell may have functions of its own but still has potential to further differentiate
  • cyte - fully differentiated
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7
Q

what are the two main types of extracellular material (connective tissue) and the subtypes

A

1) amorphous - shapeless
2) fibrous - 3 types
1. collagen
2. reticular
3. elastic

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8
Q

describe the characteristics of collagen, reticular and elastic fibres how strong, what colour, what colour stain

A

strong, flexible, white, eosinophilic orange in verhoeffs stain, type 1 but can be varied
ret - fine network, poorly stained H&E back in reticulin stain
elas - stretchable, elastic (elastin), yellow, eosinophilic and black in verhoeffs stain

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9
Q

connective tissue proper functions

A
  • support - in abdomen help gastrointestinal tract, spleen, kidneys
  • protection - capsule against mechanical injury for lymph nodes
  • connections within locomotor system - tendons connect muscle to bone ligaments connect bone to bone
  • holds tissues together - reticulum fibres hold cells together
  • energy storage - 2 ways, 1 in elastic tendons and ligaments, 2 in fat tissue
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10
Q

connective tissue proper types

A
• loose (higher ratio of cells to fibres)
• adipose (many fat cells)
• dense (lower ratio of cells to fibres)
- regularly arranged 
- irregularly arranged 
eg - horse skin
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11
Q

list the 8 cells associated with connective tissue

A

1) mesenchymal cells
2) fibroblast
3) fibrocyte
4) macrophage
5) fat cell - adipocyte
6) mast cell
7) plasma cell
8) melanocyte

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12
Q

where is mesenchymal cells found, their shape and nucleus

A
  • in embryonic tissues and some adult tissues, type of stem cell
  • stellate (star-shaped) - many cytoplasmic processes
  • oval/round nucleus
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13
Q

fibroblast shape, nucleus, where found and function

A
  • stellate or spindle-shaped
  • ovoid nucleus
  • abundant basophilic cytoplasm - lots of ribosomes as producing collagen
    synthesizes and secretes collagen and other extracellular matrix components
  • differentiates into fibrocyte
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14
Q

fribrocyte shape, nucleus, cytoplasm, function

A
  • small flattened elongated cell
  • elongated nucleus
  • very little cytoplasm - hard to distinguish
  • less active in secretion than fibroblast as stop synthesising
  • Role is to maintain connective tissue structure
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15
Q

mast cell where found, cytoplasm with what within, function

A
  • scattered, in low numbers in most connective tissues (often close to blood vessels)
  • cytoplasm filled with granules (basophilic so stain blue) containing heparin (anticoagulant), histamine (increases
    blood vessel permeability), serotonin (vasoconstrictor) and proteases
  • degranulate when tissue damaged promote inflammatory reaction
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16
Q

what are the two types of epithelial tissue and their function

A
  1. Layers or sheets - surface covering / lining – barriers / absorption / secretion - single layer simple, multi layers stratified - always a basement membrane, may not always see
  2. Glands - secretion
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17
Q

what are the 5 types of simple epithelial layers and their shapes and nuclei and example of where found

A

1) squamous - nuclei squashed, scale or plate like (flat), line duct and capillaries
eg - serous membrane of internal organs
2) cuboidal - cube-shaped cells, nucleus fills up most of the space, appear perpendicular to the surface of epithelium
eg - secretory cells of thyroid glands
3) columnar - tall cells, nucleus tends to be towards the base of teh cell, can be elongated
eg - secretory cells of prostate glands
4) pseudostratified -tall and short cells which rest on basement membrane, nuclei at different levels so looked stratified
eg - in respiratory tract
5) transitional - appears stratified but pseudostratified according to some peeps
eg - urinary bladder

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18
Q

stratified layer of epithelial how named and what are the types

A

multi layers present so not all cells attach the basement membrane
reference to the shape of the cells located on the surface
1) squamous - may undergo keratinization eg the skin
2) cuboidal
3) columnar
2) & 3) often seen in ducts of glands

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19
Q

what are the 3 surfaces for epithelial cells and list the structural specialisation

A

1) apical surface
1. cilia
2. microvilli
3. stereocilia
2) lateral
1. interdigitation
2. junctional complex
3) basal
1. basal striations
2. basement membrane
3) hemidesmosomes

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20
Q

what are stereocillia, interdigitation and junctional complex

A

large microvilli; non-motile; increase surface area for absorption / secretion;
e.g. in epithelial cells of epididymis
interlocking structure
occluding type
- tight junctions (zonula occludens) adhering type - seals them off - waterproofing
- desmosomes (zonula / macula adherens) communicating type - like super glue between cells eg in heart muscle
- gap junctions (nexus) - communication junctions, open channel between cells

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21
Q

what are basal striations and hemidesmosomes

A
  • invaginations or infoldings of basal surface of cells; to increase surface area for active transport of substances into and out of cell
    attach cell to extracellular matrix
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22
Q

development of endocrine and exocrine glands

A

both arise similarly as localised proliferation of epithelial
endocrine - lose connection to surface
exocrine - retain connection to the surface

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23
Q

exocrine glands what comprised of and how they secrete

A

Exocrine glands comprise one or several secretory units which are connected to a surface(of tissue, duct, lumen etc.) by a system of ducts - thus their secretory product is discharged onto the body surfaces or into visceral lumina. These glands produce enzymes, milk, sweat and other secretions.

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24
Q

morphology of exocrine glands what are the two opposites

A

simple - one or more secretory units within single unbranched duct
compound - multiple secretory units within system of branched ducts

tubular - secretory unit in shape of tube - cuboidal
alveolar (acinar) - secretory unit in shape of sphere
tubuloalveolar - both types of secretory units present

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25
different classifcations of exocrine based on mode of secretion
1) merocrine - only secretory product released from cell; exocytosis and released once bound to cell membrane 2) apocrine - product is membrane-bound and secreted along with some cell membrane and cytoplasmic material of the cell; 3) holocrine - the whole cell disintegrates to form the secretion and releases the product, very high turnover tissues
26
different classifications of exocrine cells based on nature of secretion and characteristics
1) mucus - thick & viscous - cell accumulates material in apical cytoplasm (pale stained) & nucleus pushed towards base and flattened - cell referred to as mucous cell - Looks like fairy floss 2) serous - thin & watery - cell nucleus spherical & near central - secretory granules in apical cytoplasm - cell referred to as serous cell - Non-distinct
27
what are veterinary positions based upon
based on a plantigrade - palms of the hand and paws on the ground - stance with all limbs in pronation
28
define planta, pronate, supinate,
Planta - sole of the feet Pronate - turn towards/inwards - fingers toes pointing forward Supinate - turn outwards
29
what is the words for the top and bottom surface of the animal foot
dorsal upper surface of foot, palmar bottom surface of foot in forelimb plantar bottom surface of foot in hind limb
30
define axial and appendicular
axial in the middle line of the body, appendicular the appendages
31
3 parts of the thoracic cavity
1) costal - towards ribs 2) sternal - towards sternum 3) vertebra - towards spine
32
define flexion, extension, hyperextension, adduct and abduct
Flexion - fold up, reducing angle In a joint extension - increasing angle hyperextension- dorsal flexaion - over extension Adduct- bring in to the body/midline abduct- take away, away from the midline
33
what tissues associated with | osteo - o, arthr articular, chondro, myo mysium, ligamentum
bones, joints, cartilage, muscles, liagments
34
what tissues assocated with | tend teno, endo peri epi fascial, neurium, phelb, thelium, lympathic, meso peri
tendons, fascia, nerves, blood vessels, skin, lymph nodes, mesentery
35
what does each of these prefixes mean | epi, peri, endo, dia, meta, infra, sub, supra, ante, anti
upon, around, within, between, change/after, beneath, under, above, before, against
36
what is epiphysis and periosteum
beyond the growth plate (physis is growth plate) | periosteum - membrane around bones
37
what are the 4 areas of the skeleton for the forelimb
1) limb girdle 2) brachium 3) antebrachium 4) manus
38
bones of the pectoral limb | limb girdle, brachium and antebrachium
``` limb scapula - lies against rib cage attached via muscles - lies dorsally clavicle and coracoid lay toward sternum brachium humerus antebrachium radius cranial to ulna and runs medial ulna caudal to radius and runs laterally olecranon - sharp part on ulna ```
39
pectoral limb bones of the manus
1) carpus - some may be lost others fused 1. radial 2. intermediate 3. ulnar 4. accessory 2) carpals (1-4 could be 5) - named medial to lateral so thumb first (horse just has 3) 3) metacarpus (5 metacarpal bones) - 5 digits 4) phalanges 2 on first metacarpus and 3 on the rest name - proximal, middle, distal, 1st, 2nd, 3rd
40
pelvic limb what are the 4 areas
limb girdle (pelvis thigh crus pes
41
bones of the pelvic limb limb girdle, thigh and crus
``` limb ilium - cranial and more dorsal ischium - caudal part you sit on pubis - ventral arch creates complete circle thigh femur (+patella and sesamoids) crus tibia - weight bearing bone fibula - lateral to tibia, most species almost lost ```
42
bones of the pelvic limb pes
1) tarus - 3 rows of tarsal bones 1. talus and calcaneus (makes heel bones) 2. centrale distal to talus 2) tarsals (1-4 could be 5) 3) metatarsals - 5 metatarsal bones 4) 2-5 phalanges on each
43
what is the seasomoid and novicular bone
Seasomoid bones on plantar or palmar and they are paired and can slide between metacarps and metatarsal and phalanges Novicular bone - distal palmara seasomoid in horses
44
list 6 features on bones
1) condyle 2) epicondyle 3) tuberosity 4) fossa 5) foramen 6) trochlea
45
what is a condyle, trochlea epicondyle
all features on bones - Condyle - generally rounded where impacted other bone and joint there - surface where meeting another bone, articular facet - flattened trochlea - grove shape where bones fit together - distal end of fibula has a trochlea - Epicondyle - either side of the condyle, process - anything that is sticking out can be large or small named based on tendon attachment
46
what is a tuberosity, fossa and foramen
- tuberosity (tubercle/trochanter) - any lump on a bone like olecranon bone mostly where ligaments or tendons attach if on a forelimb tubercle if on a hind limb than trochanter - present on the femur - Fossa - a dent, region of a bone generally filled with muscle, cavity - larger space like cranial cavity fissure - a gap, canal - a longer open ridge, duct - tubular shape hole (foramen) - Foramen - hole
47
name two specialised bones
- splanchnic bones - bone that forms within viscera - like bone in penis for dogs, cow has bone in the heart - pneumatic bones - extension of air sac in the bone
48
what is systemic and regional anatomy
systemic - To observe and deduce function and dysfunction and hence identify which systems are affected. Regional - To prepare for clinical examination, surgery, and routine procedures including injection and biopsy.
49
where located and function of jugular vein, caudal vena cava, portal vein, carotid artery
Jugular vein - comes down the neck and drains into the heart Caudal vena cava - drains back the rest of the body Portal vein - drains the guts into the liver - all the materials absorbed from intestines Carotid artery - the artery that goes up the neck
50
position of female urethra in terms of anus
comes out just ventral
51
what lays cranial and caudal to the kidneys
cranial - adrenal glands | caudal - ovaries
52
what makes up the musculoskeletal system
1) bones 2) joints - cartilage 3) muscles 4) tendons - ties muscle to bone - specialised ligaments 5) ligaments 6) fascia - generalised collagen
53
where nuchal ligament, supraspinous ligament, sacrosiactic ligament and collateral ligament
Nuchal ligament becomes the supraspinous ligament (above the spine, along the spinous processes of the vertebrae) Sacrosiactic ligament connects the sacrum to part of the pelvis Collateral ligament get either side of each hinge joint
54
What makes up the fluid compartments of the body and what total of body weight and what made up of and how much extracellular water
intracellular compartment 2/3 of TBW - high concentratin of K+, Mg++, phosphates and proteins extracellular compartment 1/4 of TBW - high concentration of Na+, Cl-, Ca2+, HCO3 1. Interstitial - 3/4 of extracellular water 2. Plasma - 1/4 of extracellular water
55
dehydration what is normal, when get reduced skin turgor, increased heart rate and collapse
normal less than 5% ski turgor reduced 6-8% increase HR 8-10% collapse 12-15%
56
Na+, K+, Cl- and Ca2+ when higher interstitial fluid or intracellular fluid
Na+ higher interstitial K+ higher intracellular Cl- higher interstitial Ca2+ higher interstitial
57
define molarity (M) and molality (m)
Molarity (M)- concentration (g/L)/molecular weight | Molality (m)- moles of solute/Kg solvent - Kg have different pressures important
58
define osmolarity and osmolality
Osmolarity (osmotic concentration): concentration of particles/L in solution and is independent of the size or weight of the particles. Sodium and potassium same osmolarity ➣ = number particles/mole x concentration/L (Osm/L)
59
diffusion of a charged solute - what do they move down and presence of what increase and decreases diffusion time what does it create
Electrolytes will also diffuse down a concentration gradient and charge gradient Presence of other similarly charged molecules will slow diffusion Presence of oppositely charged molecules will accelerate diffusion Creates a diffusion potential
60
hypertonic and hypotonic solutions what in terms of osmotic pressure and what movement
hypertonic -- When the osmotic pressure of the solution outside the cells is higher than the osmotic pressure inside the cells • Net movement of water out of cell & cell shrinks & crenates Hypotonic compartment or solution • When the solution outside of the cells has a lower osmotic pressure than the cytoplasm of the cells, the solution is hypotonic with respect to the cells. • Water moves into cell & cell expands, haemolysis
61
list the 5 functions of the cardiovascular
1. Exchange of substances with environment 2. Transport of substrates and O2 to cells 3. Removal of metabolites and CO2 from cells 4. Thermoregulation 5. Immune cells and mediators
62
function of the aorta, large arteries, small arteries and vena cava
aorta - pulse dampening and distribution large arteries - distribution of arterial blood small arteries - distribution and resistance vena cava - collection of venous blood
63
capillaries what percentage of blood within what regulated by and density controlled by
5% of blood volume regulated by neural and metabolic mechanisms and local mediates, precapillary sphincters control blood flow to capillary bed Capillary density is proportional to the metabolic activity of the cells in the tissue – Muscles and glands have the highest density – Subcutaneous and cartilage tissue have the lowest density
64
what are the 3 types of capillaries where found and special characteristics
1) continuous capillaries - found in muscle, skin, lung, fat and connective tissue, contain wide junction or clefts between endothelial cells 2) fenestrated capillaries - found in kidney, intestine, endocrine glands, joints, endothelial cells have pores called fenestrae 3) discontinuous capillaries - found in bone marrow, liver and spleen, wide clefts between adjacent endothelial cells
65
arteries and arterioles
arteries - surrounding sheath of at least two continuous layers of innervated vascular smooth muscle cells arterioles - only a single continuous layer of vascular smooth muscle cells
66
movement of molecules across capillary wall
1) diffusion 2) transcytosis or pinocytosis 3) bulk flow via starlings forces - main driving force
67
bulk flow - starlings forces what are they and do they add to adsorption or filtration
1. Hydrostatic pressure in the capillary (Pc). is the pressure exerted on the inside of the capillary walls by the blood (35 mm Hg at the arterial end of the capillary and 15 mm Hg at the venous end). Filtration 2. Hydrostatic pressure in the interstitial fluid (Pif) - pressure exerted on capillary by interstitial fluid negligent - absorption 3. Oncotic pressure in the capillary (πc). Absorption Osmotic force exerted by plasma proteins which is equal to about 25 mmHg and drives fluid back into the capillary 4. Oncotic pressure in the interstitial fluid (πif). Filtration This is very low and has minimal effect.
68
what starling force is dominant at the arteriole and venous end of the capillary
Hydrostatic forces favouring filtration are greatest at the arterial ends of capillaries Oncotic osmotic pressure predominates at the venous ends of the capillaries ensuring 90% of the fluid is reabsorbed
69
list the 4 main functions of the lymphathic system
1) the control of blood volume and extracellular volume - return excess filtered fluid to blood and return leaked protein to blood 2) main pathway for the absorption of fat in small intestine and lipid soluble vitamins 3) pathway by which the cells of the immune system circulate between the blood, peripheral tissues and lymph nodes 4) Major role in metabolism and in the turnover of extracellular matrix constituents eg hyaluronan and other glycosaminoglycans.
70
what lymphatic ducts drain into the circulatory system
thoracic duct, right lympathic duct drains into the large central veins
71
initial lymphatics where and how interstitial moves within
Site of interstitial fluid absorption Lymphatics are able to suck fluid up - due to smooth muscle - Propulsion of lymph dependent on extrinsic issue deformation of initial lymphatics to open and close lymphatic inlet valves - massages lymph downstream into the collecting ducts
72
collecting lymphatics what valves, what muscle and what attached to
* Bicuspid valves * Contractile smooth muscle * Attached to connective tissue by anchoring filaments
73
Movement of lymph what types of pumps and how work
intrinsic lymphatic pumps - rhythmic contraction of lymphatic smooth muscle propels lymph downstream, bicuspid valves prevent backflow lymphangions inportant in sucking fluid from initial lymphs extrinsic - muscle movement (main pressure) - skeletal muscle propulsion of lymph dependent on extrinsic tissue deformation massages lymph downstream
74
what stimuli increases movement of lymph
1) Skeletal muscle contraction 2) Vasomotion and pulse pressure changes in neighbouring arterioles 3) Intestines: the rhythmic smooth muscle contraction that occurs during peristalsis. 4) Diaphragm contraction 5) Respiration 6) Walking, running, massage 7) External tissue compression
75
right lymphatic duct and thoracic lymph duct where lymph comes from and drain into what
Right lymphatic duct • Lymph from right side of head and neck, right forelimb and part of the thorax enters blood at the junction of the right internal jugular and subclavian veins Thoracic lymph duct • Lymph from the rest of the body enters blood at the junction of the left internal jugular and subclavian veins
76
causes of oedema
- Decrease concentration of plasma protein - Increased capillary permeability - Increased venous pressure
77
what is lymphoedema and treatment
Lymphatic system not working properly - not just lack of movement - Lack of skeletal muscle contraction massage, compression bandages and exercise.
78
list 6 causes of lymphoedema
1) surgery - removal of lymph nodes 2) radiotherapy - block lymph nodes with fibrous tissue 3) accidental trauma may tear lymphatic vessels 4) parasites - block 5) paralysis limb prevents lymphatic pumping - more oedema 6) chronic venous insufficiency involves lymphatics running along side the veins
79
key functions of biological membranes
1) selective barrier 2) organisation 3) transport 4) control information flow 5) cell-cell interactions 6) reactions (enzyme)
80
membrane lipid families are made up of
1) phospholipids 2) sphingolipids 3) cholesterol
81
List and describe the factors affecting membrane fluidity and permeability
1) membrane lipid tail length - decreases with length increase in van der wall interactions 2) degree of unsaturated fatty acids - unsaturated have kinks don't pack together well increase in membrane fluidity 3) temperature - increase with increase temp 4) cholesterol - reduced fluidity of membrane so structurally necessary
82
how do charged molecules diffuse through the membrane examples and what effects this
cross in their non-charged form such as NH3 but not in charged NH4+ and pH determines whether charged or not
83
two types of plasma membrane proteins and types within
1) integral membrane proteins 1. span entire membrane - many alpha helices 2. integral monotopic proteins dont span entire membrane can be attached to lipids 2) peripherally associated membrane proteins - non covalently bound and often attached to integral proteins
84
types of gated ion channels and what type of movement and what is the driving force for this movement
1) voltage gated specific channel for each molecule 2) chemical or ligand gated eg acetylcholine binds pens channel 3) mechanically-gated - sound waves in inner ear SIMPLE DIFFUSION - driving force is concentration of Na+ and K+
85
electro-chemical gradients what equation determines charge on membrane so determines whether gated channels are open or closed
nernst equation | Ex (equilibrium potential) = (61mV/charge) log10 x (internal concentration/external concentration)
86
ligand gated ion channels example of two external ligands what bind to and what effect
1) Acetylcholine (ACh) - affect depends on which channel it binds to 1. Ionotropic receptor ○ Nicotinic Ach receptor ○ Opens Na+ ion channel ○ Depolarization 2. Metabotrophic receptor ○ Muscarinic receptor ○ Opens K+ ion channel ○ Hyperpolarization 2) Gamma amino butyric acid (GABA) - Binding at certain synapses in the central nervous system - Admits Cl- ions into the cell - Inhibits the creation of a nerve impulse.
87
facilitated diffusion compared to diffusion in terms of speed, and what limited by
much faster and limited by amount of binding sites on carrier protein and rate is limited by concentration and number of channels
88
what occurs with facilitated diffusion - list steps and example
1) molecule enters and binds to receptor within carrier protein 2) triggers conformational change of carrier protein allowing entry to other side of membrane 3) once molecule released protein shape reverts to original shape glucose transport
89
Example of an active transport enzyme structure and functions
Na+/K+ ATPase 3 receptors for Na+ (inside) and 2 for K+ (outside) ATPase cleaves ATP to ADP liberated energy causes conformational change roles: maintains lower Na+ and higher K+ inside cell controls cell volume by regulation of ion (osmosis) establishes net charge on plasma membrane - important for action potentials
90
secondary active transport what driven by types and examples
gradient established by Na+/K+ ATPase pump 1) Symporters or cotransporters - The sodium ions flow down their concentration gradient (driving force) while the glucose molecules are transported up theirs. 2) Antiporters or exchanges - Substances are transported in opposite directions Electrochemical gradient for Na+ drives H+ or Ca++
91
examples of cell membrane transport
1) ion channels 1. voltage gated 2. ligand gated 3. motor sensory 2) facilitated diffusion 3) primary active transport 4) secondary active transport 1. symporter 2. antiporter
92
List the 3 types of endocytosis
1) non-receptor mediated pinocytosis 2) receptor mediated endocytosis 3) phagocytosis
93
non-receptor mediated pinocytosis what occurs
Continuous nonspecific uptake of extracellular fluid and small dissolved molecules 1. Vesicle buds off from plasma membrane 2. Vesicle transported intact, releasing contents to exterior by exocytosis or fuses with a lysosome 3. Membrane components recycled to the plasma membrane
94
receptor mediated endocytosis what are the two ways and example of what transports
1) Via clathrin–coated pits in epithelial and phagocytic cell membranes Pits contain integral protein receptors for specific molecules being endocytosed 1. Molecule binds to receptors in clathrin pits - the clathrin (protein) isn't specific it just provides the framework 2. Vesicle forms around the molecules bound 2) Via caveolin-coated pits (Caveolae) in cell membranes of vascular endothelial cells and adipocytes ○ The caveolin (protein) isn't specific it just provides the framework ○ Transport of albumin ○ Folate receptor
95
phagocytosis when occurs and how
- Endocytosis of large particulate matter such as microorganisms or cell debris - Receptor-mediated - Carried out by specialised phagocytic cells - immune-related - cells that phagocytise foreign antigens act as antigen presenting cells 1. Microbe recognised by receptor 2. Phagosome forms 3. Phagosome fuses with lysosome (phagolysosome) 4. Microbes killed by proteolytic enzymes, reactive oxygen species (ROS) and nitric oxide (NO)