Biology for Nursing Practice SEM1

stroke volume (SV)

- amount of blood ejected from the left ventricle in one heartbeat - SV = EDV- ESV - at rest SV = ~ 70mL - SV is influenced by: 1. preload (increase preload > increased SV) 2. contractility (increase heart contractility > increased SV) 3. afterload (increase afterload > decreased SV) - Frank-Starling Law: SV increases in response to an increase in the volume of blood filling the heart (when all other factors remain constant) - end diastolic volume (EDV): influenced by venous return, filling time, stretch in ventricles (preload, increased EDV > increased SV. - end systolic volume (ESV): influenced by contractility, force the ventricle has to overcome (afterload), increased contractility > decreased ESV > increased SV, increased afterload > increased ESV > decreased SV

uterine tubes (aka oviduct, fallopian tubes)

- ampulla: central region, site of fertilisation - isthmus: narrowest, site of sperm maturation - collect ovulated oocytes

anuria

- an absence of urine or a volume of 100mL or less in 24 hours - causes: acute kidney injury, chronic kidney disease

surface landmarks

- anterior (front) - posterior (back) - base of the heart is actually on the top, superior, the point of attachment for large vessels (kind of between the ventricles and atriums) - apex of the heart is actually at the bottom, inferior

anti-diuretic hormone (ADH)

- aquaporins (water channels) open in the DCT and collecting tubule cells - function: water permeability of the collecting tubule increases (water gets out from tubular space > to the interstitial space > back to the circulation) - result: the production of small volume of concentrated urine

aorta

- arises from left ventricle - supples oxygenated blood to the body

pulmonary trunk/pulmonary arteries

- arises from right ventricle - branches into left and right pulmonary arteries - carries deoxygenated blood to the left and right lungs

arteries and arterioles (regulation of blood flow)

- arteries > arterioles - elastic and muscular - smaller lumen (than veins and venules) - thick walls, lots of smooth muscle - can change size of vessel lumen = vasoconstriction and dilation = arterioles site of BP control - high pressure system - regulate blood flow to capillaries

excitation and inhibition

- as well as not being all-or-nothing, graded potentials also don't just have to make the membrane more positive - they can be excitatory or inhibitory

1. resting membrane potential

- at 'rest', a neuron has fewer positive ions inside compared to outside (the resting membrane potential is -70mV) - when the neuron is 'at rest' it's not actually resting at all = working hard to set up concentration gradients - the resting membrane potential is achieved through the actions of an active ion pump = Na+/K+ ATPase (pumps 3 Na+ out, pulls only 2 K+ in... net positive outside) - at rest 80% of our oxygen goes to maintaining the resting membrane potential - Na+/K+ ATPase ACTIVE (always): working to pump 3 Na+ out, pulls only 2 K+ in - Na+ leakage channel OPEN: Na+ moving in down concentration gradient - K+ leakage channel OPEN: K+ moving out down concentration gradient - voltage-gated K+ and Na+ CLOSED

menstrual phase

- at the start of the cycle lasts for approx. 5 days - declining levels of progesterone: spiral arteries constrict, blocks flow to str. functionalis, glandular tissue die - surface epithelium disrupted (vessels rupture) - stratum functionalis (sloughed off = including blood, serous fluid, endometrial tissue; menstrual flow discharged, loses 40 ml blood & 35 ml serous fluid

what is the path involved in the flow of blood > filtrate > urine?

- blood comes into the kidney via the venal artery - afferent arterioles sit in the glomerulus - filtrate travels from the glomerulus through the nephron of the kidney - filtrate becomes urine which drains from the collecting duct - through the minor and major calyces - into the renal pelvis - to the ureter

regulation of ionic blood concentration/acid-base balance

- blood pH needs to be 7.35-7.45 to maintain homeostasis (alkalosis = pH above 7.45, acidosis = pH below 7.35) - most acid-base balance is maintained by the kidneys via a major buffering system: carbonic acid bicarbonate buffer system (mechanism involving the balance of carbonic acid = H2CO3, bicarbonate ion = HCO-3, carbon dioxide = CO2), phosphate buffer system

how is blood pressure determined?

- blood pressure determined by: cardiac output + peripheral resistance - regulated by nervous and endocrine systems - influenced by the resistance (PR) to blood flow in the peripheral vessels and the cardiac output (CO)

during forceful breathing, are inspiration and expiration active or passive?

- both are active - forced inspiration (accessory inspiratory muscles assist in raising the ribs and move the sternum, increase in lung volume, reduction in alveolar pressure) - forced expiration (internal intercostal muscles depress ribs which decrease thoracic and lung volume, contraction of anterior abdominal muscles further increases pressure resulting in increased airflow out of the lungs)

shoulder vs. hip

- both ball-and-socket but: shoulder more freely moveable, shallowness of cavity, looseness of capsule while hip is stabilised by deep cavity, tight capsule & ligaments, tendons - shoulder most dislocated - hip can withstand body's weight

white and gray matter in the spinal cord vs brain

- brain: outer = gray, inner = white - spinal cord: outer = white, inner = gray

the bronchial tree

- branching of airways from the trachea - the bronchial tree consists of macroscopic airways that begin at the trachea and continue through the terminal bronchioles - trachea > main bronchi > lobar bronchi > segmental bronchi > bronchioles > terminal bronchioles

urinary bladder

- capacity: moderately full (500mL), max (800mL) - rugae (folding of the bladder wall): in a relaxed bladder = wrinkled, highly distensible - bladder infection can persist in the trigone region at the base of the bladder

transport of carbon dioxide

- carbon dioxide is transported in the blood in three ways: dissolved in plasma (7%), buffered with water as carbonic acid (70%) by carbonic anhydrase in RBCs, bound to proteins, particularly haemoglobin in RBCs (HbCO2) - this buffering system is important as a rise in CO2 by 10% will double respiratory rate (vs O2)

carbon monoxide

- carbon monoxide (CO) binds to haemoglobin with a higher affinity (200x greater) than oxygen, and at the same binding site - prevents oxygen from binding > tissue becomes hypoxic

HR & SV determine cardiac output

- cardiac output (CO) = the amount of blood ejected from one ventricle per minute - to increase the cardiac output: increase stroke volume (SV), increase heart rate (HR), OR increase both - if venous return (VR) reduced, then less blood pumped out (unless compensatory mechanisms activated) - vigorous exercise: CO = 190bpm x 115mL/beat > 22L/min for a fit person, up to 35L/min for world class athlete (larger SV)

1. transport

- carries O2 from lungs to peripheral tissues - picks up CO2 in peripheral tissues and transports to the lungs - distributes nutrients absorbed by the digestive tract and storage in adipose tissue or liver - carries hormones from endocrine glands to their target cells - absorbs wastes produced by cells and carries to kidneys for excretion

arterial system

- carries blood away from heart - high pressure - pressure reservoir - no valves - small lumen, thick walls

venous system

- carries blood into heart - low pressure - blood reservoir - valves prevent back flow due to gravitational pull - large lumen, thin walls

arteries

- carry blood away from the heart to the capillaries - carry oxygenated blood (with one exception) - artery = away from heart - thick, elastic muscular wall

heart sounds

- caused by turbulence in blood flow with valve closure - first sound = 'lubb' (loud, caused by movement of blood in ventricles + vibration of ventricular walls with closure of atrioventricular valves, best heard at apex of heart) - second sound = 'dump' (softer & shorter, occurs with closure of semilunar valves, best heard towards base of heart)

necrosis

- causes: injury/damage, mechanical, chemical, infection, immune response - process: swelling, release of intracellular contents, inflammatory response, harmful to surrounding cells.

connective tissue (CT): bone

- cells + fibres + amorphous ground substance (AGS)/ matrix - cells: osteoblast, osteocyte, osteoclast - fibres: collagen (organic) - matrix: mineral salts (inorganic)

cells to tissues

- cells from a common embryological origin + their intercellular components from tissues - tissues have one or more specific functions - specialised tissues from organs - organs form organisms = organs maintain homeostasis, protect, support, communication

ependymal cell function

- columnal epithelial cells with cilia on apical end - line fluid cavities in the brain and spinal cord - produce and circulate cerebrospinal fluid (CSF)

long bone arrangement

- compact bone (periphery of diaphysis) - spongy bone (epiphysis and metaphysis = end of a long bone)

joint dislocation

- complete separation of 2 articulating bony surfaces - often caused by a sudden impact to the joint - a partial or incomplete dislocation is called a subluxation - common sites: shoulder, finger, patella, elbow and hip

skeletal muscle

- composed of muscle fibres surrounded by connective tissue (protects muscle; brings in blood vessels & nerves, groups muscle cells together, increasing power of contraction, connects muscle to bone = tendon) - location: skeletal muscle attaches to bone - nuclei: multinucleated, at periphery of cells - appearance: striated (light and dark bands on surface of cells) - control: voluntary - connective tissue layers (endomysium = within muscle: surrounds each muscle cell, perimysium =around muscle: surrounds bundles of 10-100 muscle cells, epimysium = upon muscle: surrounds entire muscle) - muscle fibre = myofiber - origin: point that remains stationary during contraction, generally proximal end, muscle may arise from several different places or bone - insertion: point that moves during contraction, generally distal end - muscle shapes: arrangement of muscle cells determines power & range of movement of muscle (more cells = more power, longer cells = more range of movement) - direction: e.g. transverse abdominus - size of muscle: e.g. gluteus maximus - shape: e.g. deltoid (triangular) - number of origins: e.g. biceps brachii 2 origins - action: e.g. flexor digitorum superficialis

what characteristics of rbcs make them suited to carry oxygen?

- composition: no nucleus or organelles = more space for haemoglobin, no mitochondria = doesn't need to use the oxygen they carry, packed with haemoglobin= ability to transport O2/CO2 - size: small and flexible so they can fit through narrow blood vessels - shape: biconcave, allowing them to bend for flexibility whilst increasing surface area for absorption

ligament

- connect bone to bone and stabilise joints - dense fibrous connective tissue comprised mainly of collagen - poor blood supply > implications for healing. - gradually lengthen under tension and return to their original shape when tension removed (unless stretched too far or for a prolonged time)

arrector pili muscle

- connect to each hair root - smooth muscle (contracts in response to nerve signals from the sympathetic nervous system, external hair shaft 'stand up')

spinal cord structure

- connected to the brain through the brain stem - broken down into four regions: cervical, thoracic, lumbar, sacral - protected by the vertebral bones that make up to vertebral column - the spinal cord itself ends at the upper lumbar vertebrae

tissue types

- connective tissue - epithelial tissue - muscle tissue (skeletal, cardiac, smooth) - nervous tissue

serosa

- connective tissue + simple squamous epithelium - thin layer - begins in lower part of oesophagus & ends before rectum - covers all organs & wall cavities NOT open to outside of body - secretes slipper fluid

scrotum: structure-function

- consists of loose skin and underlying subcutaneous layer - hangs testes from the root (attached portion) of the penis

classification

- constituents (fibres < cells = loose, fibres > cells = dense) - arrangement (parallel = regular, non-parallel = irregular)

lysosomes

- contains several types of digestive enzymes. - works best at acidic pH (~5) - structure: membrane enclosed vesicles, form from Golgi complex - functions: digest substances that enter a cell via endocytosis and transport. final products of digestion into cytosol, carry out autophagy (the digestion of worn-out organelles), implement autolysis (the digestion of an entire cell), accomplish extracellular digestion

larynx

- contains the vocal cords which allow for phonation (talking = closed passage, breathing = open passage) - clear speech also requires articulation = the modification of these sounds by the tongue, teeth, and lips

pancreas exocrine pancreatic solution

- contains: digestive enzymes; water; bicarbonate ions - proteases stored as inactive zymogen granules - activated in small intestine; prevent auto digestion of pancreas - controlled by 2 hormones: secretin & CCK - stimulus for release of hormones is lipids in duodenum - vagus nerve can stimulate pancreatic secretion 1. chyme enters duodenum & stimulates local release of CCK & secretin 2. CCK promotes exocytosis of zymogens & enzymes from pancreatic acinar cells 3. secretin causes duct cells to add water & bicarbonate ions = alkaline fluid 4. pancreatic enzymes can function at optimal pH once released to duodenum

how the heart beats: the cardiac cycle

- contraction and relaxation of chambers occurs in a tightly controlled and ordered sequence - occurs in concert with valve opening and closing to allow uni-directional passage of blood through the heart - contractions are synchronised by electrical impulses generated within the heart - atria contract first > blood pushed into ventricles - then ventricles contract > blood pushed into pulmonary trunk (pulmonary arteries) and aorta - brief resting phase then the whole cycle starts again

nucleus

- control centre of the cell - regulates gene expression - stores genetic material

How does the heart itself get blood?

- coronary circulation - right (RCA) and left (LCA) arteries branch off the ascending aorta - blood vessel course is along the epicardium, branches sent into the myocardium - heart drained by coronary veins - coronary artery disease (CAD) = partial/total blockage of coronary arteries>angina/heart attack

surface epithelium

- covers & lines all natural surfaces of the body

feedback 'loop' or system

- cycle of event in which status of a condition is continually monitored, evaluated & changed as needed - stimulus is a disruption to homeostasis

gallbladder biliary tree

- cystic duct extends from gallbladder to unite with common hepatic duct = common bile duct - joins with pancreatic duct - empties into hepatopancreatic ampulla before being released into duodenum

parasympathetic nervous system (PNS)

- decreased metabolic rate - decreased heart rate and blood pressure - increased secretion by salivary and digestive glands - increased motility and blood flow in the digestive tract - stimulation of urination and defecation

anaemia

- decreased number of rbcs or amount of HB - deficiencies: iron, B12, intrinsic factors - decreased EPO production - excessive abc destruction: haemolytic anaemia - hereditary Hb deficits - sickle cell anaemia - consequences of anaemia: (tissue hypoxia > SOB, dizziness, lethargy), (reduced blood viscosity > heart failure, dizziness), and (reduced blood osmolarity > tissue oedema)

actions of ADH

- decreases urine production - causes kidneys to return water to blood > less urine - decreases water lost through sweating - causes constriction of BV > increase BP

defibrilator vs pacemaker

- defibrillator: ICD (Implantable Cardioverter Defibrillator), detects tachycardia and signals to regulate and slow down the heartbeat, defibrillators contain a pacemaker with an additional ability to 'shock' a non-beating heart back to life - pacemaker: detects bradycardia and signals to speed up the heartbeat by atrial and/or ventricular contractions, will only activate as needed

pulmonary veins

- delivers oxygenated blood from the lungs to the heart - drains into the left atrium

articular capsule

- dense connective tissue - surrounds joints - thickening in capsule form ligaments

excitatory (more positive membrane potential)

- depolarisation - a neurotransmitter will open ligand-gated Na+ channels - positive ions move in

AV node

- depolarisation reaches junction of atria and ventricles - also has pacemaker cells but not normally active - a brief delay in the signal

platelets

- derived from megakaryocytes - contain membrane and mitochondria - anucleate (non-nucleus) - contain enzymes essential for haemostasis - secrete vasoconstrictors, clotting factors, growth factors, chemical attractants - activated when exposed to collagen - stop bleeding by stick together to plug damaged blood vessel walls

reabsorption loop of henle

- descending limb: freely permeable to H2O, not permeable to NaCI, filtrate becomes increasingly concentrated as H2O leaves by osmosis - ascending limb: impermeable to H2O, permeable to NaCI, filtrate becomes increasingly dilute as salt is reabsorbed

determinants of skeletal health

- developmental growth - biomechanical strain - neuroendocrine function - calcium homestasis - nutrition - fracture, wear, inchemia - infection - inflammation - metabolic disease - cancer

inspiration

- diaphragm moves downwards during contraction and rib cage moves outwards as external intercostals contract - active as muscles are contracting and this requires energy

expiration

- diaphragm relaxes and moves upwards - external intercostals relax and compress the chest cavity - this decreases chest cavity and increasing pressure causing air to flow out - passive as it doesn't require energy

long bone anatomy

- diaphysis (through growth) = shaft, compact (solid) bone - epiphysis (upon growth) = ends of bone, spongy bone - metaphysis = between diaphysis & epiphysis, contains the epiphyseal region (growth plate) - articular (joint) cartilage =covers epiphyses.

pulse pressure

- difference between systolic and diastolic pressures - increases when stroke volume increases or vascular compliance decreases - compliance tends to decrease with age (arteriosclerosis) and pressure rises - pulse pressure can be used to take a pulse to determine heart rate and rhythmicity - can also be used to stem bleeding - most frequent site used to measure pulse rate is in the carpus with the radial artery = radial pulse

integrative effects

- different but complementary effects, called integrative effects - important in coordinating the activities of diverse physiological systems - E.G. the differing effects of calcitriol (hormonally active vit D) and parathyroid hormone on tissues involved in calcium metabolism

ion channels vs. ion pumps

- diffusion = movement along/down a concentration gradient - diffusion can occur directly across a membrane or through a channel (does not require energy = passive transport) - sometimes, ions need to move against the concentration gradient - this will occur via a pump (requires energy = ATP = active transport)

2. regulating pH and ion composition in tissue

- diffusion of ion between tissue and blood (calcium high in the tissue > moves into blood, calcium low in the tissue > moves out of blood) - absorbs and neutralises acids generated by active tissue (E.G. lactate = lactic acid = produced from anerobic respiration)

euchromatin (EC)

- dispersed - lightly stained - ACTIVE cell

large intestine + rectum & anus defecation

- distension of rectal wall triggers defecation reflex - internal anal sphincter (smooth muscle) relaxes to allow anal canal to open - distension elicits sensation that signal urge to defecate - if external and sphincter (skeletal muscle) is relaxed voluntarily then defecation occurs - bowel movement vary: 2-3 times per day > 3-4 per week

endocrine system

- ductless and release hormones into the surrounding fluid - controls activities by releasing hormones - most hormones - enter interstitial fluid and are carried to target tissues by blood - endocrine system helps regulate virtually all types of body cells - some hormones affect various organs, and some cells are responsive to more than one hormone

living bone

- dynamic & ever-changing - composed of many different tissues (E.G. bone, cartilage, nerves, fat etc) - number of bones: 270 at birth but 206 in adult

meniscus

- each knee joint has a medial meniscus and a lateral meniscus - structure (two wedge-shaped pieces of cartilage, tough and rubbery) - function (shock absorber, assist with the rotational stability created by the anterior cruciate ligament)

summation of EPSPs and IPSPs

- each neuron will receive inputs (i.e. form synapses) from MANY other neurons - whether the postsynaptic neuron fires an action potential depends on the SUM of all of the incoming information - if the net input is inhibitory > action potential prevented - if the net input is excitatory > action potential is triggered

spermatic ducts-for sperm transport

- efferent ductules: small ciliated ducts collecting sperm from rete testes and transporting it to epididymis - epididymis (epi= over, didymis=testis) (head, body and tail): long coiled duct adhering to posterior of testis, site of sperm maturation and storage (fertile for 60 days), sperm undergo functional maturation here for ~2 weeks - ductus deferens (peristalsis during orgasm): muscular tube 45 cm long passing up from scrotum through inguinal canal to posterior surface of bladder - ejaculatory duct: 2 cm duct formed from ductus deferens and seminal vesicle and passing through prostate to empty into urethra

pericardium (protective tissue covering)

- encases, protects the heart - fibrous pericardium - serous pericardium (parietal, visceral) - fluid between the layers allows for frictionless movement of the heart

histology of the uterus (microscopic - 3 layers)

- endometrium (innermost): simple columnar epithelium > underlying, connective tissue and glands - myometrium (middle layer): 3 layers of smooth muscle, contracts during childbirth to expel foetus - perimetrium (outermost): connective tissue

small intestine secretory cells

- enterocytes - goblet cells - paneth cells - enteroendocrine cells

temperature and waste

- epidermis (control skin permeability and water loss) - dermis (hair when cold arrector pili muscles pull hair upright creating goose bumps, eccrine glands produces sweat 90% water, released when skin is hot and has a cooling effect as evaporated) - hypodermis (adipose tissue > stores lipids for fuel and thermal insulation)

pain, sensation, pressure, temperature

- epidermis (merkel cells > deep layer of epidermis, sensory neuron extensions, detect pain and temperature) - hairs (delicate touch sensation) - dermis (dermal papillae > tactile corpuscles = receptor to light touch, reticular layer > lamellated corpuscles = receptors to deep pressure and vibration)

barrier to microorganisms

- epidermis (prevent entry of pathogens, coordinates immune response to pathogens, langerhans cells/ antigen presenting cells) - apocrine (sweat glands produce watery secretion, flush surface, sebaceous glands, secrete sebum, anti-bacterial properties) - dermis (papillary layer> prevents spread of pathogens)

vitamin D processing, Ca2+ metabolism

- epidermis (synthesis vitamin D3 epidermal cells in stratum spinosum and stratum basale, convert steroid component to cholecalciferol > vitamin D3)

protective layers of the spinal cord

- epidural space = 'real' space between dura and bone

glandular epithelium

- epithelial cells that produce and release a secretion that differs in composition from tissue fluid or blood, mucus, gastric secretions, sebum, milk

protection of underlying tissues (impact, abrasion, fluid loss, chemicals)

- epithelium/keratin (protection) - dermis (papillary layer > aerolar CT, reticular layer > dense irregular CT, collagen fibres > strong resist stretch, elastic fibres > provides elasticity) - hypodermis (adipose tissue, under skin and surrounding organs, cushions organs)

gallbladder microstructure

- epithelium: columnar cells - lamina propria: connective tissue - muscularis: smooth muscle - perimuscularis: fibrous connective tissue - serosa

ion movement across neuronal membranes

- essential to the excitable, conductive and secretory functions of neurons - plasma membranes prevent diffusion - allow passage of specific ions allowed by channels and pumps - channels and pumps that allow the movement of these ions are key: potassium (K+), sodium (Na+), calcium (Ca2+), chloride (CI-) - atom or molecule with a net electric charge due to the loss or gain of one or more electrons

large intestine + rectum & anus

- extends from ileocacecal junction to anus - consists of caecum, colon, rectum & anal canal - chyme converted into faeces - extensive action of microflora - teniae coli: 3 bands of smooth muscle - haustra: pouches of colon - epiploic appendages: fat filled sacs

maintenance of optimal temperature for spermatogenesis

- extra peritoneal: location of scrotum - scrotum muscles: cremaster muscle (skeletal muscle) = hot > relax > drop the testes away from pelvis, cold > contract > lift the testes closer to pelvis - dartos muscle (smooth muscle) = hot > relax, cold > contract > wrinkles skin reducing surface area of scrotum - testicular veins: wrap around testicular artery (pampiniform plexus) > counter current heat exchange

articular ligaments

- extracapsular - intracapsular

articular disc (meniscus)

- fibrocartilage - attached to capsule - allows bones of different shapes to fit together tightly - increase stability of joints

adventitia

- fibrous connective tissue - outer layer of the GIT organs that are NOT associated with the peritoneal cavity - includes: oral cavity, pharynx, remainder of oesophagus & rectum - binds to surrounding structures

myofibrils

- fill sarcoplasm of muscle cell (composed of myofilaments = thick and thin filaments; sliding of filaments over each other is responsible for muscle contraction) - sarcomere is the basic unit of striated muscle tissue, it is the repeating unit between 2 Z lines - striations: pattern formed by overlapping thick and thing filaments (thin filament = actin, thick filament = myosin pulls actin along length) - muscle contracts when thin filament slides over thick filament - contraction: myosin (thick filament) binds to actin (thin filaments), actin slides inward - NOTE: thick and thin filaments do not actually change in length during contraction process.

glomerulus

- filtration: blood plasma and dissolved substances (smaller than most proteins) get filtered into the glomerular capsule - together with bowman's capsule is the renal corpuscle

cerebellum

- fine motor control - balance and coordination - timing of movement - compares brains intentions with how the body is moving

permissive hormones

- first hormone is needed for the second to produce it's effect - E.G. epinephrine doesn't change the rate of energy consumption in a tissue UNLESS thyroid hormones are also present in normal concentrations

types of bones

- flat bones (cranial bones, sternum, scapulae, ribs) - long bones (humerus, radius, ulna, metacarpal, phalanges, metatarsal, tibia, fibula, femur) - short bones (tarsals, carpals) - irregular bones (vertebrae, sacrum, sesamoid bones, patella)

sequence of the cardiac cycle

- fluid moves from region of high to low pressure so blood will naturally move into low pressure chamber 1. atria relaxed, passive filling of atria, ventricles relaxed 2. atria contract, increases pressure in atria, forces AV valves open, blood flows into the ventricles, ventricles relaxed 3. atria relax, pressure decreases in atria, AV valves close, ventricles contract 4. when ventricular pressure is greater than the arterial pressure, semilunar valves pushed open, blood pushed into pulmonary artery and aorta, atria relaxed

oesophagus anatomical structure (rugae)

- folds of the mucosa & submucosa - allows expansion of the stomach - empty = holds 50 mL - full = holds 1-1.5L - pyloric sphincter: distal end of stomach, smooth muscle, prevents early discharge or stomach contents - lower (inferior) oesophageal sphincter: at gastro-oesophageal junction, transition between oesophagus & stomach

glucagon induce

- gluconeogenesis (glucose generated from non-carbohydrate sources i.e. amino acids and lactic acid) - glycogenolysis (breakdown of glycogen to glucose) - FFA in liver released as Ketones (when prolonged) - lipolysis (fatty acid release from triglycerides stored in adipocyte fat droplets)

insulin induce

- glucose uptake (in muscle and adipose tissue) - glycogenesis = glycogen synthesis (glucose stored as glycogen in liver and muscle) - fatty acid uptake (by muscle and adipose tissue) - ion uptake (especially K+ and PO4-3) - amino acid uptake and protein synthesis (formation) - glycolysis (conversion of glucose, C6H1206, into pyruvate, C3H6O3, the free energy released is used to form the high energy compounds = ATP)

leukocytes (white blood cells)

- granulocytes 1. neutrophil (helps in phagocytosis, acute, first line of defence against bacteria) 2. eosinophil (fights against parasitic infection, release toxins) 3. basophil (produces inflammatory and allergic reactions, release histamines and inflammatory mediators) - agranulocytes 4. lymphocyte: produces specific immune responses (B.Lymphocyte = humeral immunity, antibody production, T. Lymphocyte = cellular immunity, helper and cytotoxic, Natural Killer Cell = recognise and kill pathogen-infected cells) 5. monocyte (fights off bacteria, viruses and macrophages)

white matter and gray matter in the brain

- gray matter: mainly neuronal cell bodies and synapses, few axons, glial cells, capillaries - white matter: mainly myelinated axons, few cell bodies

polyuria

- greater than normal urinary volume - causes: diabetes mellitus, diabetes insipidus

appositional: bone growth in width

- growth at edge of bone - osteogenic cells > osteoblasts > bone laid down around blood vessels - concentric lamellae formed > osteons

3. restricts fluid loss

- haemostasis = preventing and stopping of bleeding - if there is a break in a vessel wall, enzymes and other substances respond to patch it up - the clotting process: blood clots are a temporary patch to prevent further blood loss and entry of pathogens to tissue

systole (contraction)

- heart chamber contracts > decrease in chamber volume - increase pressure in chamber - valves forced open - blood pushed into adjacent chamber or artery

diastole (relaxation)

- heart chamber relaxes > increase in chamber volume - decrease pressure in chamber - chamber fills with blood in preparation for next cardiac cycle - valve closes

variations in heart rate and contraction

- heart rate influenced by SNS and PNS - normal range 60-100bpm - bradycardia = slow heart rate < 60bpm - tachycardia = fast heart rate >100bpm - fibrillation = uncoordinated, irregular contractions of atria or ventricles; loss of sequential depolarization - atrial fibrillation = clot formation risk > stroke - ventricular fibrillation = impairs pumping, decrease CO; common after heart attack

heart rate

- heart rate influences how much blood is pumped out of the heart - measured from the pulse (normal resting values average 60 to 100, infants 120 beats/min or more, young adult females 72 to 80 beats/min, young adult males 64 to 72 beats/min, HR rises in again in the elderly) - bradycardia = decreased heart rate = persistent, resting adult HR < 60 (common in sleep and endurance trained athletes > increased SV) - tachycardia = increased heart rate = persistent, resting adult HR > 100 (stress, anxiety, drugs, heart disease or increased body temperature)

sympathetic nervous system (SNS)

- heightened mental alertness - increased metabolic rate - reduced digestive and urinary functions - activation of energy reserves - increased respiratory rate and dilation of respiratory passageways - elevated heart rate and blood pressure - activation of sweat glands

hepatic sinusoids: blood flow

- hepatic artery: oxygenated blood from heart - hepatic vein: partially deoxygenated blood from small intestine - drains into central vein - central veins converge to hepatic vein - flow to inferior vena cava

gallbladder bile summary

- hepatocytes produce bile that is transported by a duct system to the gallbladder for concentration & temporary storage - bile is partially an excretory product (containing components of worn-out RBCs) & partially a digestive secretion - bile contributes to digestion by emulsifying triglycerides - the fusion of individual crystals of cholesterol is the beginning of 95% of all gallstones, gallstones are problematic

hepatic lobules

- hexagonal in shape - strands of radiating cells = hepatocytes - central vein with radiating strands of hepatocytes - contains a portal triad: vein, artery + bile duct

regulation of the other thyroid hormone

- high serum calcium (parafollicular: C cells secrete) - calcitonin (decreases tubular reabsorption > increased excretion, decreases bone resorption, minor role in calcium homeostasis > PTH, Vit D3 major regulators) - regulates plasma calcium - NB therapeutic option: hypercalcaemia, Paget's, bone cancer

axon terminal

- highly branched ends of axon - where synapses are located

heterochromatin (HC)

- highly condensed - intensely stained - INACTIVE cell

hormone action

- highly variable: dependent on hormone & target cell - various targets respond differently to same hormone - GO activate synthetic or stimulatory processes OR STOP activate degradation or inhibitory processes

thyroid gland

- 'master gland of metabolism' - formed by thyroid epithelial cells surrounding proteinaceous colloid - colloid: contains thyroglobulin - follicular cells: polarized, synthesize thyroglobulin, carry out thyroid hormone biosynthesis

macrophages

- 'scavenger' defence cells - act by phagocytosis of cell debris, bacteria, cancer cells, intercellular components

ovaries

- 1 pair, almond sized organs - function: production of female gametes =oogenesis, production of steroid hormones (oestrogen and progesterone) =steroidogenesis, production of inhibin - capsule (tunica albuginea) fibrous connective tissue - germinal epithelium/ovarian surface orcoelomic epithelium, outmost layer > simple squamous epithelium covering the ovary > cuboidal epithelium - cortex: contains follicles, corpus luteum, corpus albicans + supporting connective tissues - medulla (the innermost layer): connective tissue contains vessels, nerves

skin

- 16% of body weight (heaviest organ in body) - interface between internal and environment - most extensive sensory organ of body. - 2 main components: the cutaneous membrane, accessory structures + nails + hair

liver blood supply

- 2 sources - hepatic portal system - hepatic artery (~25%): oxygenated blood - hepatic portal vein (~75%): nutrient-rich blood from GIT - portal triad: branches of hepatic artery & hepatic portal vein - carry blood into liver sinusoids - hepatocyte secretions go into blood - drains into central vein & hepatic vein - inferior vena cava and then right atrium of the heart

semen or seminal fluid

- 2-5 mL of fluid expelled during orgasm - 60% seminal vesicle fluid, 30% prostatic, 10% sperm - other components of semen: fructose (energy for sperm motility), fibrinogen (causes clotting, enzymes convert fibrinogen to fibrin), fibrinolysin liquefies semen within 30 minutes, prostaglandins stimulate female peristaltic contractions, spermine is a base stabilising sperm pH at 7.2 to 7.6

spongy bone (aka chancellous or trabecular)

- 20% skeletal mass - latticework of thin plates of bone (trabeculae) orientated along lines of stress - spaces filled with red bone marrow - location: at epiphyses and inside flat bones - function: provides strength with little weight - no Haversian canals present, thus: (no osteons, no concentric lamellae (only interstitial lamellae present), blood vessels instead present within bone marrow spaces) - bone nutrition - osteogenic cells, osteoblasts, osteoclasts: located at edge of bone close to blood vessels, thus normal diffusion occurs

general structure of large blood vessels (arteries and veins)

- 3 layers (tunica externa, tunica media, tunica intima) - continuous with heart - complexity reduces as luminal diameter decreases

the circulatory/cardiovascular system

- 3 main components: a pump = the heart, conducting tubes = blood vessels, arteries, capillaries, veins, fluid = blood

blood vessels

- 3 types: veins, capillaries, arteries - complexity reduces as luminal diameter of vessel decreases - the smaller the vessel, the less complex - 3 layers: tunica externa/adventitia = outside layer (external elastic lamina, CT = collagen & a few elastic fibres, prevents over-distension of vessel wall), tunica media = middle layer (smooth muscle and elastic CT, smooth muscle contraction & relaxation > vasoconstriction & vasodilatation > variation in luminal diameter > decrease/increase in blood flow, blood pressure, helps propel blood through vessels), tunica intima/interna = inside layer (endothelium, basement membrane, sub-endothelial CT layer, internal elastic lamina, smooth endothelial surface facilitates blood flow = minimal friction, prevents clotting, thin = squamous, endothelium> minimal distance for exchange between vessel and surrounding tissue)

muscle tissue

- 600 muscles ~ 40% male weight - ½ body weight - characteristics: extensibility = stretch without damaging, elasticity = return to original shape, contractility = shorten when stimulated with force, excitability = respond to stimuli by producing an action potential

reabsorption proximal convoluted tubule (PCT)

- 65% of filtrate volume reabsorbed - Na+, glucose, amino acids, and other nutrients actively transported; H2O and many ions follow passively - H+ and NH4+ secretion and HCO3- reabsorption to maintain blood pH - some drugs are secreted

hepatocytes

- 80% of liver's volume - produce bile. - secretory, metabolic & endocrine functions - radiate outwards from central vein to edges of lobule

peripheral resistance (opposition to blood flow)

- BP reduces with increasing distance from heart & beginning of vascular circuit (average BP 100mmHg in aorta, 0mmHg at right atrium) - reduction in BP due to vascular resistance (R) = opposition to blood flow in all vessels due to friction - influenced by 3 factors: diameter/radius of vessel (large diameter = low resistance, small diameter = high resistance), blood viscosity (decreased blood viscosity = low resistance E.G. anaemia, increased blood viscosity = high resistance E.G. dehydration), vessel length (short vessel = low resistance, long vessel = high resistance)

function of the CNS

- CNS = brain + spinal cord - information comes into the spinal cord via the PNS - that information goes up the brain - the brain integrates that information and coordinates a response - a command is sent down to the spinal cord

glial cells in the CNS and PNS

- CNS: ependymal cell, oligodendrocyte, microglia, astrocyte - PNS: Schwann cell, satellite cell

carbon monoxide (CO) poisoning

- CO has a 230x higher affinity for Hb than O2 - Hb will bind CO not O2 > tissues not getting O2 > can lead to death. - headaches, vertigo, confusion - treatment: 100% O2 therapy (pushes CO off Hb)

bone surface markings: surface anatomy

- E.G. rough areas, grooves, openings, processes - indicate specific functions (passageway, joint formation, muscle attachment site)

lipid soluble

- E.G. steroids, thyroid hormones & nitric oxide - action: diffuse through the lipid bilayer of the plasmalemma, hormone receptors are on the inside of cell trigger response inside cell - hormone only affect target cells via receptors

metabotropic receptors

- G-protein coupled receptors - signalling cascade - second messengers like cAMP and IP3 - these second messengers change response to other neurotransmitters

gastrointestinal tract (GIT)

- GIT organs: oral cavity, pharynx & oesophagus, stomach, small intestine, large intestine, rectum & anus - accessory organs: salivary glands, tongue, pancreas, liver, gallbladder

reabsorption collecting duct

- H2O reabsorption through aquaporins regulated by ADH - Na+ reabsorption and K+ secretion regulated by aldosterone - H+ and HCO3- reabsorption or secretion to maintain blood pH - urea reabsorption increased by ADH

mean arterial pressure (MAP)

- MAP = average pressure in the arteries during one cardiac cycle - MAP influenced by total peripheral resistance (TPR) - TPR = resistance blood must overcome to be pushed through the systemic circulation = opposition to blood flow - TPR influenced by: vasoconstriction (smaller vessel lumen) > increases TPR, vasodilation (larger vessel lumen) > decreases TPR - MAP = CO x TPR - MAP = diastolic + 1/3 (systolic - diastolic)

large intestine + rectum & anus chemical digestion

- NO digestive enzymes - bacteria in the lumen: gut microbiome - discharge of hydrogen, carbon dioxide & methane gases

reabsorption distal convoluted tubules

- Na+ reabsorption regulated by aldosterone - Ca2+ reabsorption regulated by parathyroid hormone (PTH) - CI- co-transporter with Na+

functions of the PNS

- PNS = all other nervous tissue - sensory information: into the spinal cord from periphery = afferent, commands out of spinal cord to periphery = efferent - two divisions: autonomic nervous system (ANS) - involuntary (unconscious control of the body, E.G. Breathing, control of BP), somatic - voluntary (conscious control of the body, E.G. moving your arm)

leukocytes (migrating from the blood)

- WBC - neutrophils, lymphocytes, eosinophils

what happens during a myocardial infarction?

- a blockage in a coronary artery disrupts blood flow to the heart, causing ischaemia (lack of oxygen) - if this is sustained (>20-40 minutes), severe ischaemia can lead to irreversible cell death

hip dysplasia

- a condition where the ball and socket of the hip joint don't form properly

the clotting process

- a delicate balance between the actions of three key components: the vascular system must contain fluid blood to function correctly, but blood must be able to clot when it is necessary to prevent excessive bleeding, there is a constant balance between the activators and inhibitors of clotting

the brain

- a typical brain is about 1.2L - brain size generally varies with body size - no correlation between brain size and intelligence - 2% of total bodyweight - uses ~20% total cardiac output

large intestine + rectum & anus faeces formation

- absorption of some electrolytes: NA+ & CI- - 90% of water removed from chyme - faeces are semi-solid by the time they reach the transverse colon - faeces: dead epithelial cells, undigested food, bacteria + water - 500mL of food residue > 150mL faeces

muscles of inspiration (active)

- accessory (sternocleidomastoid = elevates sternum, scalenes group = elevate upper ribs) - principal (external intercostal, interchondral part of internal intercostals = also elevates ribs, diaphragm = dome descends, thus increasing vertical dimension of thoracic cavity; also elevates lower ribs)

organs of the male reproductive system

- accessory organs (epididymis: site of sperm maturation, ductus deferens: conducts sperm between the epididymis and prostate gland, seminal glands: secrete fluid to add to the semen, prostate gland: secretes fluid and enzymes, urethra: conducts semen to the exterior) - gonads (testis: produces sperm an hormones) - external genitalia (penis: contains erectile tissue deposits sperm and produces pleasurable sensations during sexual activities, scrotum: surrounds the teste)

pancreas exocrine microstructure

- acinus + duct system - acinar cells (produce & transport enzymes to duodenum) - acinus is composed of serous cells surrounding small lumen - acinar cells are highly polarised, containing zymogen granules = protein secreting cell - drains into intercalated duct > intralobular duct > interlobular duct > main pancreatic duct > common bile duct

spermatozoan structure

- acrosomal cap: specialised lysosome > enzymes that digest through oocyte coat prior to fertilisation - head: contains nucleus with 23 densely packed chromosomes - neck: contains both centrioles from original spermatid - middle piece: contains mitochondria > ATP production for movement - principal piece: axoneme (central strand) surrounded by fibres - sperm tail (flagellum): very narrow tip of flagella, whiplike organelle that moves sperm, the only flagellum in body

the synapse action potential

- action potentials can't jump from one cell to another - cells need chemicals messengers to send signals to other cells: neurons, glands, or muscle cells - chemical messengers called neurotransmitters - transmitted from one cell to another at the synapse - release stimulated by the arrival of the action potential at the axon terminal

hormonal control of spermatogenesis

- actions of: testosterone, dihydrotestosterone (DHT)

liver function

- acts as interface between digestive system & the blood - bile production & secretion - metabolism: carbohydrates, lipids & proteins - detoxify & neutralise drugs/harmful substances - storage of glycogen, vitamins & minerals - removal of defective blood cells from circulations

anterior pituitary hormones

- adrenocorticotropic hormone (ACTH) - thyroid-stimulating hormone (TSH) - growth hormone (GH) - gonadotropins - follicle-stimulating hormone (FSH) - luteinizing hormone (LH) - prolactin (PRL) - melanocyte-stimulating hormone (MSH)

oesophagus histological structure

- adventitia: distal oesophagus = SEROSA - muscularis externa: proximal 1/3 = skeletal muscle, middle 1/3 = mixture of skeletal & smooth muscle, distal 1/3 = smooth muscle - submucosa: oesophageal glands, facilitate transport, protects mucosa - mucosa: non-keratinised stratified squamous epithelium

triiodothyronine (T3)

- affects almost every physiological process - most formed in liver from T4 (thyroid gland produces less) - mainly formed from DID and MIT - active form - potency XXXXX - shorter duration of action - half life 1 day - used to treat myxoedema coma - total T3 normal blood range 5-12 ng/dL: free T4 80-190 ng/dL

factors contributing to plasma filtration

- afferent arterioles diameter > efferent arteriole diameter - blood hydrostatic pressure > colloid osmotic pressure > capsular pressure - peritubular capillaries: arise from efferent arterioles, travel alongside cortical nephrons - vasa recta: thin-walled looping vessels that parallel to the nephron loop in juxta medullary nephron - glomerulus: capillary networks that are fed and drained by afferent and efferent arterioles (filter blood) - both peritubular capillaries and vasa recta collect water and solutes reabsorbed by the nephrons AND deliver other solutes to nephrons

postsynaptic neuron

- after the synapse - neuron 1 - the one contributing the receptors - responding to the NT

X-Ray of lungs

- air in X-ray images appear black vs. muscles, fat and fluid (shades of grey) - bone appears white (radio-opaque)

the peripheral nervous system

- all other nervous tissue - predominantly peripheral nerves = cable-like bundles of neuron axons - not enclosed by bone or meninges - sensory afferent division: towards brain, ganglia = collection of neuron cell bodies, nerve endings (free, encapsulated) - motor efferent division: away from brain

fenestrated capillaries

- allow blood plasma to pass through the pores (fenestrae) - prevent blood cells and platelet to passthrough to the filtrate - therefore if damaged = blood cells and platelet pass through to the filtrate

podocytes and filtration slits

- allow small protein to pass - stops the medium protein from passing through the filtrate - therefore if damaged = medium protein in filtrate

left atrioventricular (bicuspid/mitral valve)

- allows blood to flow from left atrium to left ventricle - has 2 cusps

right atrioventricular (tricuspid valve)

- allows blood to flow from right atrium to right ventricle - has 3 cusps

basement membrane

- allows small and medium sized protein to pass - stops large protein to pass through the filtrate - therefore if damaged = stops large protein to pass through the filtrate

decreased glucose

- alpha cells secrete glucagon (increase glycogenolysis = glycogen breakdown > glucose release) - adipose tissue (lipolysis = fatty acid release from triglycerides stored in adipocyte fat droplets) - liver (increase glycogenolysis = glycogen breakdown > glucose release, increase gluconeogenesis = amino acid and lactic acid > converted to glucose, increase FFA is converted to Ketone released = when prolonged)

antidiuretic hormone (ADH)

- also known as arginine vasopressin (AVP) - released in response to a variety of stimuli: primarily increased solute concentration of blood (sensed by osmoreceptors in DCT and collecting duct), OR a decrease in blood pressure or volume - inhibited by: increase in extracellular fluid volume, alcohol - primary function: decrease water lost from kidney, causes vasoconstriction

microglia

- ameboid shape when activated - mobile

water soluble

- amino acid based - E.G. include amine, peptide, protein hormones - NOT lipid soluble (so CANNOT diffuse through plasma membrane) - action: bind to receptors on the target cell surface, use the 1st/2nd messenger system to trigger a response with the cell - hormones only affect target cells via receptors

six types of synovial joints

- hinge (a convex portion of one bone fits into a concave portion of another bone, movement is limited to flexion and extension as the joint opens and closes) - ball and socket (the spherical end of one bone fits into a concave socket of another bone) - pivot (a rounded part of one bone fits into the groove of another bone, these joints permit a rotation movement of one bone around another) - condyloid (an oval surface of one bone fits into a concavity of another bone) - gliding (these joints have a flat or slightly curved surface, permitting gliding movements, these joints are bound by ligaments, and movement in all directions is restricted, the joint moves back and forth and side to side) - saddle (similar to condyloid joints, but these joints permit greater movement)

gallbladder

- hollow pear-shaped organ - located in fossa in posterior surface of liver's right love - anterior of the duodenum. - divided into 3 regions: fundus, body, neck

hypothalamus (cerebral cortex)

- homeostasis - E.G. thermostat for your body, hunger, circadian rhythms - links nervous system to endocrine system

control of hormone secretion

- hormones secreted in bursts - as stimulation increases bursts increase in frequency - in absence of stimulation, bursts are minimal or inhibited - regulated by: neural signals, chemical changes in blood, other hormones

endocrine vs. nervous

- how is this message transmitted? (E= by circulating body fluids, N=across synaptic cleft) - specificity of response determined by: (E= expression of receptors, N= expression of receptors and anatomic location of nerve terminals) - speed of response (E= slower, N= faster) - persistence of response (E= long lasting, N= usually short duration) - area of effect (E= often diffuse, N= often very localised)

urinary pH

- hydrogen (H+) - ammonium-ion (NH4+) secretion - bicarbonate (HCO-3) reabsorption

inhibitory (more negative membrane potential)

- hyperpolarisation - a neurotransmitter will open ligand-gated CI- channels - negative ions move in

how might hypertension influence the flow of filtrate through the nephron and how this might lead to the presence of protein in the urine?

- hypertension causes: damage to renal arteries and glomerular capillaries - glomerular factor: chronic HT can result in end-organ microvascular damage (weakening of vessel walls), damage to capillaries/glomerulus compromises the function of the filtration membrane - tubular factor chronic HT can cause increase in glomerular filtration rate (GFR), less effective reabsorption function of the proximal convoluted tubule as high GFR results in insufficient time for the PCT tore absorb substances such as protein, glucose, salt and water - hence the protein will remain in the filtrate > presence in urine

blood glucose levels

- hypoglycaemia (low blood sugar) - normal levels (4-7.8 mmol/L) - hyperglycaemia (high blood sugar)

organs in the endocrine system

- hypothalamus - pituitary - thyroid - parathyroid - pancreas - adrenal - ovaries - testes

What happens when the vocal folds are dysfunctional or gone?

- if the nerve supplying the larynx is damaged patients typically have a hoarse voice - if the larynx needs to be removed, the surgeons will create an opening in the neck for breathing = then typically need an artificial device to allow speech

nose

- important for sensing (olfactory) - avoid noxious atmosphere (E.G. natural gas is scented)

exocrine gland definition

a gland that secretes substances (electrolytes, proteins or enzymes) straight to a target site via ducts or tubes

endoplasmic reticulum (ER)

a network of membrane - enclosed sacs or tubules that extend throughout the cytoplasm and connect to the nuclear envelope

catheter specimens

a sample through the lumen of a latex catheter or from a self-sealing port

a) scapula b) clavicle c) fibula d) humerus e) ulna f) phalanges of hand g) femur h) patellaI i) cranial (portion of skull) j) rib k) vertebrae

a) flat b) long c) long d) long e) long f) long and short - depends on ratio g) long h) sesamoid i) flat j) flat k) irregular

5. regulating body temperature

absorbs heat generated by active tissue, redistributes it (high body temp > blood rushes to skin, heat lost, low body temp > blood rushes away from skin and towards essential organs, retaining heat)

axon hillock

action potential generated here

left semilunar (aortic valve)

allow blood to flow from left ventricle to aorta

right semilunar (pulmonary valve)

allows blood to flow from the right ventricle to the pulmonary arteries

production of egg cells (oogenesis)

- in females: oogenesis begins before birth in the fetus - millions of oogonia produced by mitosis by the 3-4th month of development - however, mitosis ceases with no new oogonia therefore there are a finite number of oocytes and most oogonia will degenerate before birth - at birth: approx. 200,000 developing oocytes left in each ovary > most will degenerate before puberty - at puberty: approx. 40,000 remain - between puberty & menopause: approx. 400 oocytes will reach maturity & ovulate; remaining will degenerate

multiunit

- in large arteries & airways, arrectoer pili muscles, iris - individual cells have their own motor nerve ending thus independent contraction

visceral (single unit)

- in most blood vessels & walls of hollow organs (stomach, bladder etc.) - autorhythmic - gap junctions between cells, thus cells contract in unison

sertoli cells

- in the lumen of seminiferous tubules - support cells - produce androgen binding protein (ABP) - "serum proteins" eg transferrin - enzymes (convert testosterone to estrogen and to 5α-dihydrotestosterone (DHT)) -hormones eg inhibin

hypoxaemia

- inadequate oxygen carrying capacity = ventilation-perfusion mismatch - decrease respiratory drive: damage to medulla due to stroke/injury, drugs, central sleep apnoea, metabolic alkalosis (decrease CO2 in blood) - muscle weakness: diaphragm in motor neuron disease - environment: altitude, suffocation

oxytocin

- increased released in response to: childbirth, nursing, sexual arousal (function unknown), sensory input (neuroendocrine reflex) - stimulates contraction of: smooth muscle walls of uterus, mammary gland myoepithelial cells releasing milk

increased testosterone

- increased testosterone would NOT boost sperm count. It would actually decrease it - increased levels of testosterone inhibit the production of GnRH in the hypothalamus - this will reduce FSH production from anterior pituitary - FSH stimulates sperm production, less FSH is likely to reduce sperm count

basal metabolism

- increases basal metabolic rate (BMR) - increases body temp (calorigenesis) - increases appetite - cold adaptation - heat intolerance & sweating

luteinizing hormone (LH)

- induces ovulation, promotes secretion of estrogen & progestins - OR stimulates production of sex hormones (androgens)

GIT functions

- ingestion: taking in food - digestion: breaking it down into nutrients - absorption: pulling nutrients into bloodstream - excretion: removing waste

mouth function

- ingests food - chews &/ mixes food - begins chemical breakdown of carbohydrates

cardiac contractility

- inherent strength and vigour of heart contraction during systole - autonomic nervous system can regulate cardiac contractility: SNS can increase contractility of cardiac myocytes, PNS has no effect on cardiac contractility - with SNS activity the heart pumps harder > more blood can be ejected even if HR stays the same

synovial membrane

- inner lining of capsule - secretes synovial fluid - brings nutrients to cartilage & removes wastes

parasympathetic nervous system (PNS): rest and digest

- innervates: SA node, AV node - controls/influences: heart rate only - parasympathetic stimulation on the heart leads to: decrease rate of SA and AV node firing > decrease HR, decreased cardiac output, no effect on ventricular contraction

sympathetic nervous system (SNS): fight or flight

- innervates: SA node, AV node, ventricular myocardium - controls/influences: heart rate, force of contraction - sympathetic stimulation on the heart leads to: increase SA and AV node firing > increase HR, increase force of ventricular contraction, increase cardiac output

composition of bone

- inorganic (calcium phosphate = hydroxyapatite = crystals arrayed in a protein matrix, resist compressive forces) - organic (connective tissue = cells, type 1 collagen fibrils organised into lamellae, tensile strength, resistance to bending and/or torsional forces) - mineralization (calcification) = hardening of matrix when mineral crystals deposit around collagen fibres

myelin sheath

- insulates the axon - speeds up action potential

cell body (soma)

- integrates signal from dendrites - houses organelles - site of metabolism, rich in mitochondria

goblet cells

- interspersed between enterocytes - increase as progress down tract - produce mucins - protection against acidic contents - lubrication of lining of GIT

bone growth

- interstitial = growth in length - appositional = grow in width

cytosol

- intracellular fluid - 55% of total cell volume - 75-90% water - 10-25% dissolved & suspended ions, glucose, amino acids, fatty acids, proteins, lipids, ATP, waste products and organic molecules

bone development and remodelling

- intramembranous ossification > flat bones - endochondral ossification > long bones

oogenesis

- involves mitosis and 2 meiosis - before birth: oogonia mitosis > primary oocytes, primary oocytes enter meiotic prophase > arrest until follicular growth begins (at puberty) - puberty: at the completion of meiosis I > secondary oocyte + first polar are formed, secondary oocytes start meiosis II but arrest at metaphase of meiosis II - if fertilisation occurs: resumption of meiosis II > produces ovum + second polar body, at the end of meiosis II, oogenesis produces (one functional ovum, two or three polar bodies = nonfunctional; disintegrate)

intramembranous ossification

- involves the formation of bone within mesenchyme arranged in sheetlike layers that resemble membranes 1. development of ossification centre: osteoblasts secrete organic extracellular matrix 2. calcification: calcium and other mineral salts are deposited and extracellular matrix calcifies (hardens) 3. formation of trabeculae: extracellular matrix develops into trabeculae that fuse to form spongy bone 4. development of the periosteum: mesenchyme at the periphery of the bone develops into the periosteum

ion pumps in neuronal membranes

- ions normally move from low to high concentration - ion pumps use energy to push ions against their concentration gradient

a voided specimen

- is a sample of fresh urine collected in a clean container - the first voided specimen of the day is preferred > most likely to contain substantial urinary components that have accumulated during the night

joints

- joints hold bones together but can permit movement - point of contact between: adjacent bones, cartilage & bone, teeth & bone

juxtaglomerular apparatus

- juxtaglomerular cells (structure: modified smooth muscle cells, location: the afferent arteriole, function: endocrine cells produce renin) - macula densa (structure: an area of closely packed specialised cells, location: lining the DCT where DCT touches glomerulus, function: monitors sodium level in the urinary filtrate) - extraglomerular mesangial cells (location: extraglomerular, function: role of these cells is unclear = supporting cells, clearance)

hair follicles

- keratinous filament growing out of the epidermis - lined by cells from the basal layer of the epidermis

5 stages of normal homeostasis

- key players = endothelium + platelets + clotting factors 1. vessel injury prompts spasm 2. platelet plug formation 3. fibrin forms and blood clot develops = coagulation 4. clot retraction 5. clot lysis

organs of the urinary system

- kidneys - ureters (connect kidneys to urinary bladder) - urinary bladder (temporary storage for the urine) - urethra (transports the urine from the urinary bladder out of the body)

external genitalia labia

- labia majora: hair-covered, longitudinal folds comprised mostly of adipose covered by skin - labia minora: hairless, flattened, longitudinal folds located in the cleft between the labia majora; composed largely of CT

nerve fibres

- lamellated corpuscles (receptors to deep pressure and vibration) - tactile corpuscles (receptor to light touch, reticular layer, located in a dermal papilla adjacent to the basement membrane and stratum basale of the overlying epidermis)

struture of rbc's is key to gas exchange and blood movement

- large surface area to volume ratio (fast and efficient gas exchange) - can form stacks (orderly movement through blood vessels) - flexible (can bend and flex when travelling through the blood stream, allows for shape changes when passing through small capillaries)

proliferate phase

- lasts from ~day 6 to ~day 13 (most variable timeline) - associated with follicular phase in the ovaries Increasing oestrogen levels: stratum functionalis cells proliferate to a thickness of ~4-10 mm, mitosis of endothelial, stromal & glandular cells in basal endometrium, elongation via hyperplasia of glands; regeneration & coiling of arterioles; renewal of surface epithelial layer

ion channels in neuronal membranes (channels > passive transport)

- leakage: always open or randomly go between open and closed - gated: open and close in response to a stimulus (voltage, chemical/ligand, mechanical)

bundle branches and Purkinje fibres

- left and right bundles pass signal to ventricles - stimulation of myocardium in ventricles from apex up - contraction happens in that direction too

systemic circuit (LV>body>RA)

- left side of the heart pumps oxygenated blood to the rest of body - supplies all organs with blood - blood distributed via aorta, arteries and arterioles - high pressure system > blood needs to be propelled around entire body - left ventricles: thick, muscular walls in line with big workload

4. defends against pathogens

- leukocytes = white blood cells (wbcs) - wbcs can migrate into tissue to remove debris - some wbcs produce antibodies that can neutralise OR tag invading organisms/foreign substances for destruction

pancreas

- lies posteriorly to stomach - extends laterally from duodenum towards spleen - exocrine pancreas = produces & secretes digestive enzymes - endocrine pancreas = produces & secretes hormones - 13cm long; 2.5cm thick - head: situated in C-shaped curve of duodenum - body (neck): extends slightly upward - tail: situated near the spleen - pancreatic duct - endocrine = pancreatic islets: produce insulin & glucagon - exocrine = acini form lobules separated by septa: produce pancreatic solution

ionotropic receptors

- ligand-gated ion channel - open and close in response to NT - no second messengers - excitatory = glutamate - inhibitory = GABA

mucosa

- line cavities that open to the exterior - epithelial cells form a barrier to microbes - in the GIT, comprised of: epithelium, lamina propria, muscularis mucosae

endosteum (within bone)

- lines all internal cavities - osteogenic cells

accessory organs of the GIT

- liver - salivary glands - gallbladder - pancreas

paneth cells

- located in base of crypts between villi - contain lysozyme - antibacterial activity

enteroendocrine cells

- located in crypts - secretes variety of hormones - aids in GIT motility, gastric emptying & mechanical digestion

chief cells

- located in lower regions of gastric glands - protein synthesising & exporting cell - granules contain inactive pepsinogen - converted into pepsin in presence of HCI

parietal cells

- located in upper regions of gastric glands - secrete H+ and CI- which combine to form HCI - secrete intrinsic factor - secrete activity initiated through various mechanisms (i.e. hormones, distension, neural)

alveoli

- location (lungs have millions of alveoli which lie in direct contact with capillary) - structure (the alveoli wall = 1 cell thick + the capillary wall + the basement membrane that lies between them = the respiratory membrane ~ 0.5um thick

stratified cuboidal epithelium

- location (sweat glands, salivary glands, and the mammary glands) - function (protective tissue)

stratified columnar epithelium

- location (the male urethra and the ducts of some glands) - function (secretes and protects)

smooth muscle

- location: attached to hair follicles, in walls of hollow organs (E.G. blood vessels, GIT, bladder) - nucleus: single, central nucleus - appearance: non-striated - control: involuntary - structure: small, flat, single, central nucleus, lack T tubules, little sarcoplasmic reticulum, thick and thin filaments are NOT orderly arranged - sliding of thick and thin filaments is transferred to intermediate filaments (then dense bodies attached to sarcolemma, sliding of filaments results in 'twisting' of cell causing it to contract) - two types of smooth muscle: visceral, multiunit

stomach

- location: between oesophagus & duodenum - j shaped - anatomical regions: cardia, fundus, body, pylorus - main function: tore ingested food, mechanically breakdown food

periosteum (surrounding bone)

- location: covers exterior of bone, except articular cartilage - structure: source of bone forming cells = osteoprogenitor cells

microvilli

- location: digestive structure - structure: numerous, short extensions - function: increase surface area

bone cells: osteoblasts

- location: edge of bone, i.e. periosteum, endosteum, within Haversian canals - structure: single nucleus, rounded - function: bone forming cells, synthesise osteoid/unmineralized bone (organic matter of bone matrix e.g. collagen, proteins), become osteocytes or bone lining cells

cartilage: elastic cartilage

- location: external ear, epiglottis - structure: web-like mesh of elastic fibres amongst lacunae - functions: provides flexible, elastic support; maintains shape

cardiac muscle

- location: heart - nuclei: single, central nucleus - appearance: striated, short, branched muscle cells - control: involuntary, autorhythmic - arrangement (cells connected by intercalated discs, concentrated patches of adhering and communicating junctions, same arrangement of thick and thin filaments as skeletal muscle) - contraction: larger T tubules (more mitochondria = aerobic respiration, most Ca2+ enters from extracellular fluid during contraction, prolonged delivery of Ca2+ to sarcoplasm produces a contraction, contraction lasts 10-15 x longer than in skeletal muscle cell), autorhythmic cells (contract without stimulation from nervous system, contract ~ 75 x/min > requires lots of O2)

cartilage: fibrocartilage cartilage

- location: intervertebral discs, meniscus, pubic symphysis - structure: rows of chondrocytes in lacunae parallel bundles of collagen - functions: resists compression & absorbs shock

cartilage: hyaline (articular)

- location: over ends of bones at moveable joints; trachea, immature skeleton - structure: clear, glassy, fine collagen fibres - functions: smooth surfaces prevent friction (thus pain) when joints move; holds airways open

skeletal muscle structure

- long, cylindrical, multinucleated cells - arise from fusion of 100+ myoblasts during embryogenesis - cannot divide - sarcolemma: muscle cell plasma membrane (plasmalemma) - sarcoplasm: muscle cell cytoplasm, filled with myofibrils - transverse (T) tubule: invaginations of the sarcolemma into the centre of the cell - sarcoplasmic reticulum: stores Ca2+ in a relaxed muscle cell - mitochondria: provide energy for contraction - glycogen: stored energy for muscle - myoglobin: red pigment that binds O2

small intestine

- longest protein of the GIT - site of most enzymatic digestion & absorption - three subdivisions: duodenum (~ 15%), jejunum (~ 40%), ileum (~ 60%)

endometrial thickness during cycle

- low (1 mm) - only basal layer --- - growth of functional layer via tissue hyperplasia (>2-3 mm) --- - maximum height (5-6 mm) - tissue hypertrophy

translation

- mRNA > protein - occurs in the cytoplasm - mRNA is decoded by a ribosome - amino acids align to make a specific protein

circulation of CSF

- made by the choroid plexus lining the ventricles - circulates to bathe the entire brain and spinal cord in the subarachnoid space - reabsorbed on the surface of the brain (arachnoid granulations) into venous circulation

brain stem

- made up of midbrain, pons and medulla - connects brain to spinal cord - controls involuntary muscles (keeps you alive) - E.G. breathing, HR, BP

the central nervous system

- made up of the brain and spinal cord - brain encased within the skull (cranial cavity) - spinal cord is encased in the spinal canal, within the vertebrae - spinal cord is continuous with the brain (extends caudally, terminating at lumbar vertebrae) - protected by meninges - bathed in cerebrospinal fluid (CSF)

bone cells: osteocytes

- main bone cell (90% cells) - origin: terminally differentiated osteoblast that have become trapped in matrix they have deposited - location: inside cavities (lacunae) WITHIN bone matrix, i.e. not at edge - structure: single nucleus, stellate, have a delicate cytoplasmic process ('fingers') - function: initiate mineralisation, mediate response to bone strain, regulate bone formation (sclerostin), mediate repair of bone matrix damage - connected by canaliculi (communication between cells, exchange of nutrients and waste products, translating mechanical strain into biochemical signals)

gallbladder functions

- main function = bile storage - concentration of bile - respond to intestinal hormones to empty/refill bile stores - regulates composition of bile - controls flow of bile into duodenum

nucleoplasm

- maintains shape and structure of nucleus - contains chromatin

endothelium function

- maintenance of selectively permeability barrier - maintenance of non- thrombogenic (anti-clotting) barrier - modulation of blood flow - regulation & modulation of immune response - hormonal synthesis & other metabolic activities - modification of lipoproteins

actions of insulin

- major anabolic hormone (can be stored 28 days)

measurement of blood pressure

- measured at brachial artery - listening for Korotkoff sounds - produced by turbulent flow in arteries as pressure is released from the blood pressure cuff

electrocardiogram (ECG)

- measures the electrical activity of the heart - recording electrical changes in that accompany heartbeat - differences in electrical activity correlate with phases of contraction & relaxation of cardiac muscle - electrical activity detected on body's surface via electrodes - changes to the ECG wave can indicate problems within the heart = pathology - where in wave abnormalities are seen > can tell us which part of the heart is functioning abnormally - failure can occur anywhere in the conduction system

stomach function

- mechanical digestion - begins chemical digestion - releases food into duodenum as chyme

how the small intestine contributes to the process of digestion?

- mechanical: comprised of two processes (segmentation & peristalsis), segmentation (the local mixing of chyme with intestinal juices, repeated smooth muscle contraction & relaxation, sloshing back and forth), peristalsis (propels chyme onwards through the GIT, weak movement with migrating motility complexes) - chemical: integral proteins which function as enzymes can be found on the microvilli, microvilli enzymes located on enterocytes (enterokinase: activates trysin, disaccaridases: digest disaccardies to monosaccharides), aminopeptidases - digest small peptides into amino acids

vesicle

- membrane bound organelles - contain: water, proteins/enzymes/hormones, wastes

protective layers of the CNS

- meninges = three layers of connective tissue membrane - dura mater (2 layers: periosteal and meningeal layers, adheres to bone and meningeal layer below, only loosely covers brain) - arachnoid mater (finger like structures project into dura) - pia mater (follows gyri and sulci of the brain, closely adheres to surface of the brain)

modes of secretion by glandular epithelium

- merocrine (secretion contained within vesicles, released into a duct) - apocrine (secretion contained within the cytoplasm, cell membrane buds off to form carrier vesicles) - holocrine (secretion contained within the cytoplasm, the cell ruptures to release secretion)

proximal convoluted tubules structure

- microvilli - simple cuboidal epithelium - abundant mitochondria - basal cell membrane invaginated

small intestine function

- mixes chyme with digestive juices - mechanical digestion via segmentation - absorbs nutrients

uterine cervix

- more rigid, less contractile than rest of uterus - endometrium: 2-3 mm thick, little change in height over cycle, epithelial lining = mucus secreting columnar epithelium, stroma = contains large, branched glands > secrete mucus into cervical canal > mucous plug except around ovulation when consistency of secretion changes to seromucous, no spiral arteries, not shed during menstrual phase

astrocyte function

- most abundant glial cell in the CNS - forms blood-brain-barrier: separates blood from nervous tissue - structural support to neurons - promote homeostasis: regulates ions, nutrients, and gases around neurons - absorb and recycle neurotransmitters - from scar after CNS injury

fibroblasts

- most common CT cells - produce all fibres and ECM in CT - repair (respond to injury by dividing and producing large amount of collagen, form scar tissue)

secretory phase

- most constant timeline lasting ~14 days - associated with the luteal phase in the ovaries: hormones produced by corpus luteum (progesterone) promote thickening of stratum functionalis, glands become active, secreting a variety of products to nourish the developing embryo, if no fertilisation occurs, menstrual phase will begin

control of breathing

- mostly passively controlled - also active control possible

muscle functions

- motion: walking, heartbeat, GIT - stabilising body positions: posture - regulating organ volumes: sphincters - movement of substances: blood, urine, food, air - producing heat: involuntary contractions of skeletal muscle (shivering)

stratified squamous epithelium

- mouth, oesophagus & anus - tough for protection

ventilation - breathing

- movement of air into (inspiration) and out (expiration) of the lungs - this movement of air is created by changing the volume of the chest cavity - inhaled air does not push lungs open - the diaphragm and external intercostal muscles increase the volume of the chest cavity and pull the lungs open (negative pressure in the lungs vs. higher atmospheric pressure, draws air in through the nose and mouth)

structure of GIT wall

- mucosa - submucosa - muscularis - serosa

urinary bladder histology

- mucosa (inner layer): stratified = impermeable to water and small molecules, transitional epithelium = stretches readily > accommodate fluctuation of volume of the liquid inside the lumen - muscular layer: smooth muscles = detrusor muscles (when relaxed > bladder stores urine; when contracts > during urination to release urine) - adventitia (outer layer)

small intestine summary

- mucosa forms villi which increase the SA of the epithelium available for absorption & digestion - embedded in the villus is a lacteal for fat absorption - cells of epithelium include absorptive, goblet, Paneth & enteroendocrine cells - free surface of absorptive cells features micro-villi - the submucosa contains duodenal glands which secrete an alkaline mucous that helps neutralise gastric acid in chyme

ureter

- mucosa is covered with transitional epithelium > able to stretch - adventitia: outer layer connective tissue - muscular layer: smooth muscles > peristalsis

structures support uterine tubes functions

- mucosal layer = ciliated columnar: cilia > move the oocyte towards the uterus, epithelium with secretory cells that provide nutrients - muscularis layer = circular & longitudinal smooth muscle > moves oocyte along by peristalsis, fimbriae sweep oocyte into tube

stomach secretory cells

- mucous cells - parietal cells - chief cells - enteroendocrine cells

protection of the stomach (why does the stomach not digest itself?)

- mucous coat: resists action of acid & enzymes - epithelial cell replacement: cells are replaced every 3-6 days - tight junctions: epithelial cells are joined by tight junctions which prevent gastric juices from seeping between them

what happens to your cardiovascular system when running?

- muscles need more blood, so arteries dilate and HR increases - vasodilation > decreases TPR. - increased flow of blood to tissues VR increases. - increased VR > increases EDV - increased EDV > increases SV - increased SV > increases CO - increased CO > increases MAP > increases blood flow to muscles allowing to run

oesophagus

- muscular tube (~25 cm long) - transports from mouth to stomach - terminates by joining the cardiac orifice of the stomach

stomach histological structure

- muscularis externa: outer longitudinal layer, middle circular layer, inner oblique layer, assists with mechanical digestion - mucosa: simple columnar epithelium, gastric pits & glands, cells secrete alkaline mucous (protection & defence), numerous secretory cells that produce gastric secretion

capillaries (the microcirculation)

- near every cell but more extensive in tissues with high metabolic activity - E.G. muscles, liver, kidneys, brain - exchange site for nutrients & wastes between blood & tissue fluid - single cell layer of simple squamous epithelium (endothelium) & its basement membrane

inhibitory postsynaptic potential (IPSP)

- negative ions enter the postsynaptic neuron - makes membrane potential more negative (further away from threshold)

cytoskeleton

- network of three protein filaments = microfilaments (round the inside), intermediate filaments (scattered), and microtubules (spider) - aids movement of organelles - serves as a scaffold that helps determine a cell's shape and organise the cellular contents

control of the GIT

- neural control: neurons: sensory & motor, ANS (extrinsic control) & ENS (local control), different neurotransmitters lead to different effect - hormonal control: hormones released to assist with digestion, gastrin & motilin - nerves & hormones control GIT effectors: muscles, glands & blood vessels

posterior lobe of pituitary gland

- neurons of the supraoptic and paraventricular nuclei manufacture ADH and oxytocin (released by sympathetic terminals at fenestrated capillaries into the circulation from the posterior love of the pituitary)

cells of the nervous system

- neurons: the cells you think of when you think of the brain, they generate and conduct electricity (action potentials) - glia: 90% of all cells in the nervous system, the support crews, essential for function of the neurons, glia = Greek for 'glue' but do much more

function of the synapse

- neurotransmitters: chemical messengers, released from neurons, acts on receptors in the membrane of the post-synaptic neuron, will either increase or decrease the chance that cell will fire an action potential - vesicles: packets of membrane that contains neurotransmitter, fuse with presynaptic cell membrane, releasing NT

(SC) fibrous joints

- no cavity - fibrous connective tissue between bones - little or no movement (FC) - types of fibrous joints (suture: dense CT unites skull bones, immovable (FC); joining of tibia and fibula = bones united by a ligament, slightly moveable (FC); tooth in jaw = tooth held in socket by ligament, immoveable (FC))

(SC) cartilaginous joints

- no cavity - little or no movement - bones held together tightly by cartilage, E.G. Pubic symphysis

SA node

- normal heartbeat triggered by SA node = sinus rhythm - present in wall of right atria - contains specialist pacemaker cells > depolarise (action potentials) - stimulates atrial muscle to contract - conduction through internodal pathways

haemoglobin

- not just a passive courier of oxygen (changes the affinity for oxygen depending on external conditions) - binding of oxygen is a cooperative process (oxygen binding affinity of haemoglobin is increased as oxygen molecules bind to it, when one O2 binds the three following O2 bind with increasing affinity after the addition of each subsequent O2 molecule) - the saturation of 02 is about 97% after the alveoli in the systemic circulation and about 75% leaving tissues in venous circulation - affinity for oxygen increases with (lower temperature, high pH alkaline; pH of 7.4 is normal) - affinity for oxygen decreases with (high temperature, low pH = acidic) - 100mL of blood contain between 12-18g of haemoglobin - each haemoglobin molecule contains four haeme groups with iron cores to which oxygen binds - as each red cell contains about 270 million haemoglobin molecules, a single red blood cell can carry over 1 billion molecules of oxygen

loose CT

- nourishes and cushions epithelia - provides arena for immune defence against infection - binds organs together - allows passage for nerves and blood vessels through other tissues - location: underlines all epithelia, outer coverings of blood vessels, nerves, oesophagus and other organs, fascia between muscles

classification

- number of layers ( 1 layer = simple epithelium, > 1-layer stratified epithelium) - cell shape (squamous, cuboidal, columnar)

regulation of blood/volume/water balance by kidneys

- obligatory water reabsorption: proximal convoluted tubule (PCT) and descending limb of nephron loop, cannot be adjusted, 85% of filtrate recovered - facultative water reabsorption: distal convoluted tubule (DCT) and collecting tubule, precisely controlled ADH, remaining 15% possible

ovulation

- occurs as a result of Luteinising Hormone (LH) surge - completion of meiosis I in oocyte > becomes secondary oocyte + first polar body - rupture of follicular wall - release of oocyte

process enable genetic variation

- occurs in meiosis I: tetrad formation (the foursome during meiosis made by two homologous chromosomes), crossing over (exchange different segments of genetic material to form recombinant chromosomes)

transcription

- occurs in the nucleus - DNA > mRNA - a small segment of DNA containing the gene to be transcribed opens up as the hydrogen bonds between complementary bases are temporarily broken - a strand of RNA with the help of an enzyme, RNA polymerase, is formed - the DNA then bonds itself back to the original helical structure and is released

indicators of urinary system disorders

- oedema (fluid accumulation) - proteinuria (protein loss) - fever (infection) = pyelonephritis (kidney infection high grade fever) - pain: superior pubic region (bladder), superior lumbar region (kidney), pyelonephritis (kidney infection), renal calculi (kidney stones)

growth plate fractures

- often need immediate treatment - can affect how the bone will grow - improper treatment may lead to a more crooked or shorter than its opposite limb

4. repolarisation

- once the membrane potential reaches +40mV, the axon 'wants' to return to resting - voltage-gated K+ channels open (K+ rushes out of the neuron, this makes the inside of the cell more negative) - at the same time, voltage gated Na+ become inactive (this stops Na+ from continuing to flood the cell, further helping the cell return to a more negative membrane potential) - Na+/K+ ATPase ACTIVE: effect on MP is negligible -Na+ and K+ leakage channel OPEN: effect on MP is negligible - voltage-gated Na+ INACTIVE - voltage-gated K+ OPEN: K+ rushes out of axon

subcutaneous layer (hypodermis)

artery/vein, lymph vessels and subcutaneous fat

disruption to blood homeostasis

blood isn't meeting oxygen demand of tissue (hypoxaemia, anaemia, haemorrhage)

urinary calcitriol-calcium levels

by production of calcitriol

measuring the activity of the brain

can record electrical activity of the neurons using electroencephalography (EEG) - electrodes places on the skull can measure activity of groups of neurons - the amount and type of electrical activity will differ between: tasks, sleep states, disease states e.g. seizure

oligodendrocyte

cell body with many processes of cell membrane that reach out to axons

paracrine definition

cell to cell communication of paracrine factor transmitted via extracellular fluid

target cell

cell with a receptor that response to the presence of a hormone

hormone definition

chemical mediator produced by endocrine glands to help maintain homeostasis

a 24-hour specimen

collection of all urine produced in a full 24-hour period

axon

conducts electrical activity from cell body to axon terminal

urinary blood volume

conserve or eliminate water

3. depolarisation

- once the membrane potential reaches threshold, the voltage-gated Na+ open at the start of the axon (Na+ floods into the axon down the concentration gradient) - the membrane potential becomes more and more positive - the change in potential triggers more voltage-gated Na+ channels to open = the change in membrane potential is 'explosive' - this continues until the membrane potential reaches +40m - Na+/K+ ATPase ACTIVE: effect on MP is negligible - Na+ and K+ leakage channel OPEN: effect on MP is negligible - voltage-gated Na+ OPEN: Na+ floods into the axon - voltage-gated K+ CLOSED

unipolar

- one branch from the cells body - splits in to two - one end in to spinal cord, other to periphery

permissive effects

- one hormone has a permissive effect on another - first hormone is needed for the second to produce its effect. - E.G. epinephrine does not change the rate of energy consumption in a tissue unless thyroid hormones are also present in normal concentrations

neurons

- only ~10% of all cells in the CNS - can't replicate ... mostly (we have some capacity for neurogenesis) - main parts of the neuron: dendrites, cell body, axon, axon terminals

large intestine + rectum & anus histological structure

- openings of intestinal glands - simple columnar epithelium - rectum & anus (stratified squamous epithelium, mucosa is organised into longitudinal folds: anal column, depression between columns: anal sinus, function: facilitate defecation & protection against abrasion)

overview of digestion

- oral cavity (teeth = mastication, tongue, breaking down of food) - salivary glands (sublingual, submandibular and parotid) - pharynx (bolus moved to oesophagus) - oesophagus (propulsion = voluntary, peristalsis = involuntary) - stomach (mechanical digestion, chemical digestion) - small & large intestine (absorption) - rectum & anus (defecation)

nucleus of neuron

contains genetic material

bone cells: osteoclasts

- origin: hematopoietic lineage - derived from fusion of bone marrow monocytes. - location: edge of bone in pits - structure: large, multinucleate cell - function: bone dissolving cell (release lysosomal enzymes & acids that digest bone matrix)

bone cells: osteogenic cells

- origin: stem cells derived from embryonic fibroblasts, only bone cells to undergo mitosis (divide), some become: osteoblasts, osteocytes - location: edge of bone, i.e. periosteum, endosteum, within Haversian canals

structure of HB key to gas exchange

- oxygen doesn't dissolve easily in water - needs to combine with haemoglobin as only dissolved O2 can diffuse into tissue - 4x O2 per molecule of Hb - CO2 can be transported by Hb OR as a dissolved gas in plasma - CO2 (acidic) needs to be tightly controlled as can lower blood pH Hb can transport both gases simultaneously = O2 and CO2 bind different parts of the Hb molecule

posterior pituitary hormones

- oxytocin - antidiuretic hormone (ADH)

integumentary system functions

- pain, sensation, pressure, temperature - barrier to microorganisms - protection of underlying tissues (impact, abrasion, fluid loss, chemicals) - waterproof - temperature and waste - UV protection - vitamin D processing, Ca2+ metabolism - skin colour

dermis

- papillary layer (aerolar/ loose CT) > loosely packed collagen fibres - reticular layer (dense irregular CT) > tightly packed collagen fibres

mechanisms of tubular reabsorption

- paracellular reabsorption: between adjacent tubule cells, tight junctions do not completely seal off interstitial fluid from tubule fluid - transcellular reabsorption: through an individual cell

penis function

- passageway for urine AND semen - composed of tissue filled with blood sinuses - erection: these blood sinuses fill with blood; compresses veins that drain penis

gas exchange

- passive movement of molecules (in this case oxygen and carbon dioxide) from an area of high concentration to an area of low concentration - moves down a concentration gradient

how does gas exchange occur throughout the body?

- passive movement of molecules from high to low concentration > enabled by circulation generating concentration differentials E.G. O2 1. High atmospheric pressure - 159mmHg 2. 100 mmHg in alveoli vs 40 mm in pulmonary vein 3. Back to 40 mmHg in venous return to alveoli for re-oxygenation circuit

types of hormones

- peptides (derived from chains of amino acids) - amines (derived from the amino acids tyrosine and tryptophan) - steroids (derived from cholesterol)

in juxtamedullary nephrons (looks more squashed at top)

- peritubular capillaries are connected to the vasa recta - the vasa recta (part of the kidneys' urine) concentrating mechanism = counter current exchange

types of hormonal interactions

- permissive effects - additive effects - antagonistic effects - integrative effects

endocytosis

- phagocytosis (bigger) - pinocytosis (fluid)

excitatory postsynaptic potential (EPSP)

- positive ions enter the postsynaptic neuron - makes membrane potential less negative (closer to threshold)

mechanisms of venous return

- pressure Gradient (7-13 mmHg venous pressure gradient towards heart) - thoracic/respiratory pump (inhalation > thoracic cavity expands = pressure decreases, abdominal pressure increases, flow from high to low) - skeletal muscle pump (in limbs, below heart) - gravity

underwater seal drain

- prevents air & fluid from returning to the pleural space (allows air and fluid to leave chest, contains a one-way valve to prevent air & fluid returning to the chest, designed so that the device is below the level of the chest tube for gravity drainage)

sterility

- primary sterility: a couple has not been able to conceive after having had unprotected intercourse for a year - secondary sterility: after having had a first child, a couple has not managed to achieve a second pregnancy after having had unprotected intercourse for two to three years

collecting duct

- principal cells (function: reabsorb water, control: under influence of ADH = concentrate urine by passive diffusion of water into medullary interstitium) - intercalated cells (structure: cuboidal cells with microvilli, function: help maintain acid-base balance)

urinary blood supply

- process by which solutes and water are passively changed between blood of the vasa recta and interstitial fluid of the renal medulla (provides blood supply to medulla, retains NaCI in the medulla) - descending capillaries: water diffuses out of blood, NaCI diffuses into blood - ascending capillaries: water diffuses into blood, NaCI diffuses out of blood, NaCI is maintained in the medulla - counter current multiplier of nephron loop: concentrates urine via diffusion and active transport - counter current exchange of vasa recta: passive exchanged via diffusion between blood and interstitial fluid

G cells

- produce & release hormones - act locally within the intestinal lining - act on other organs (e.g. pancreas). - enterochromaffin-like cells (ECL): produces histamine - G cells: secretes gastrin

plasma cells

- produce antibodies (immunoglobulins)

bile production

- produced by hepatocytes - alkaline solution: pH 7.6-8.6 - ~1L produced per day - aid digestion & absorption - bile produced continuously throughout day - production & secretion dependent on what is ingested - between meals, bile is stored in gallbladder - components: water, bile salts, bile pigments, phospholipids, electrolytes, cholesterol, triglycerides - bile salts: emulsifying agents, hydrophobic & hydrophilic regions, important for absorption of digested lipids, recycled by enterohepatic circulation - bilirubin: bile pigment, waste product of old/damaged red blood cells, causes green colour of bile, causes brown colour of faeces

thyroxine (T4)

- produced in thyroid gland - formed by combining DIDs - inactive form - potency X - longer duration of action - half life 7 days - used to treat myxoedema coma and regular treatment of myxoedema - total T4 range in blood normal 1.0-3 ng/dL: free T3 0.25-0.65 ng/dL

carbohydrate, lipid & protein metabolism

- promotes glucose catabolism for energy - stimulates protein synthesis - increases lipolysis - enhances cholesterol excretion in bile - increase basal metabolic rate (BMR), enhance CHO consumption, increase size/number mitochondria - DNA translation and transcription = protein synthesis (but also has catabolic effects)

musculoskeletal

- promotes normal body growth and maturation of skeleton - promotes normal function and development of muscles - T3 enhances transcription of growth hormone (GH)

heart

- promotes normal cardiac function - helps modulate heart rate and BP

reproductive

- promotes normal female reproductive ability - promotes normal lactation

nervous system

- promotes normal neuronal development in fetus and infant - promotes normal neuronal function in adult enhances effects of sympathetic nervous system - acting as a neurotransmitter =T3 influences levels of serotonin > imbalance can mimic psychiatric disease

follicle-stimulating hormone (FSH)

- promotes ovarian follicle development & stimulates secretion of estrogens (OR promotes maturation of sperm) - inhibited by inhibin (peptide released by gonads)

structure linked to function

- protection from abrasion (oesophagus: stratified squamous epithelium) - vigorous mixing: mechanical disruption (stomach: oblique muscle layer) - lubrication & chemical digestion (duodenum: submucosal glands, small intestine: epithelium for absorption)

epithelial tissues

- protective, barrier layer - interface between two environment. - controls passage of substances e.g. secretion, absorption, transportation

dense irregular CT

- protects organs from injury - provides protective capsules around many organs - in the dermis of skin

normal range

- provided by normal population measurements - lung function depends on: height, age, gender, ethnicity - with age and loss of elastic recoil the FEV1 declines by about 20-30mL/year

extracellular matrix (ECM)

- provides support to the surround cells and fibres (structural + biochemical) - regulates (intercellular communication transportation of substances through CT) - amorphous ground substance (clear, colourless, viscous fluid, consists of glycans and protein and water, secreted by CT cells) viscosity (thickness) = restricts penetration by bacteria - oedema (swelling) = abnormal accumulation of interstitial fluid

epithelial tissue (the lining) microscopic

- pseudostratified columnar epithelium - lines conducting portion of respiratory tract - contains goblet cells to produce mucous to trap fine particles - cilia sweep mucous away from lungs

respiration

- pulmonary respiration (external) conduction to the alveoli for gas exchange to RBC > cell - cellular respiration (internal) ultimately to produce ATP i.e. cellular energy (remove CO2)

muscles of expiration

- quiet breathing (expiration results from passive, elastic recoil of the lungs, rib cage and diaphragm) - active breathing (internal intercostals, except interchondral part = pull ribs down, abdominals = pull ribs down, compress abdominal contents thus pushing diaphragm up)

What causes the change in size of the chest cavity?

- quiet breathing ~ 500mL of air - inhalation (diaphragm contracts = moves down, rib cage expands as rib muscles contract) - exhalation (diaphragm relaxes = moves up, rib cage gets smaller as rib muscles relax)

proximal convoluted tubules function

- reabsorption of Na2+ (Salt), H2O (water), glucose - secretion of uric acid, drug metabolites from blood capillaries into tubules

function of neurons

- receive, integrate and send 'signals' - excitable: respond to changes in environment - conductible: transmit electrical signals = action potentials - secretory: pass chemical message to other cells = neurotransmitters

right atrium (RA)

- receives deoxygenated blood from superior and inferior vena cava - pumps blood to the right ventricle

right ventricle (RV)

- receives deoxygenated blood from the right atrium - pumps blood into pulmonary artery (to the lungs)

left ventricle (LV)

- receives oxygenated blood from the left ventricle - pumps blood into the aorta (to the rest of the body)

left atrium (LA)

- receives oxygenated blood from the pulmonary veins. - pumps blood into the left ventricle

cellular communication

- receiving > transducing > responding to a signal - signal from neighbouring cells and/or extracellular environment - cell activation/suppression/proliferation/death

3 basic components to the feedback loop

- receptor (monitor): structure that monitors change in controlled condition > sends input to control centre - control centre (evaluator): sets range of values, evaluates input from receptors, generates output (nerve/chemicals) - effector (changer): receives output > produces response

medullary/marrow cavity

- red bone marrow (location: medullary cavity and trabeculae spaces, functions: site of development of blood cells) - yellow bone marrow (location: diaphysis medullary cavity, functions: fat storage)

articular cartilage

- reduces friction - absorbs shock

functions of the urinary system

- regulation of: blood ionic composition, pH, glucose levels, detoxification of free radicals, blood volume, blood pressure, blood cell formation, calcitriol-calcium levels - excretion of: waste and foreign substances

thalamus

- relay centre - cortex > thalamus > spinal cord - interconnects other parts of the brain (e.g. limbic system) - key for sensory integration, sleep, arousal

thyroid-stimulating hormone (TSH)

- released in response to thyrotropin-releasing hormone (TRH) from hypothalamus - stimulates release of thyroid hormones triiodothyronine (T3), thyroxine (T4) - decreased released when thyroid hormone levels (T3, T4) rise (negative feedback)

mucosa simple columnar epithelium

- remainder for GIT - secretes enzymes & absorbs nutrients - specialised cells - tight junctions between cells prevent simple diffusion - mucous secreted to keep surface moist - renewal rate = 7 days

kidney functional unit (nephron)

- renal corpuscle = glomerulus + glomerular capsule - proximal convoluted tubule (PCT) - nephron loop (loop of henle) = thick descending part, thin segment, thick ascending part - distal convoluted tubule (DCT) - collecting duct

kidney major structural landmarks

- renal cortex (superficial portion) = outer - renal medulla (deeper portion between cortex and sinus) = inner 1. renal pyramid (conical structure in medulla) 2. renal papilla (tip of pyramid) 3. renal column (separates pyramids) 4. kidney lobe (pyramid and overlying cortex): 6-18 lobes/kidneys

types of nephrons

- renal cortex contains: all corpuscles, proximal convoluted tubules (PCTs), distal convoluted tubules (DCTs) - renal medulla: loops of henles, collecting ducts - cortical nephrons: ~85% of all nephrons, located in the cortex - juxtamedullary nephrons: closer to renal medulla, loops of henle extend deep in the medulla into renal pyramids

renin-angiotensin-aldosterone systems

- renin is secreted by juxtaglomerular cells if blood pressure drops dramatically. - renin converts angiotensinogen > angiotensin 1 - in lungs and kidneys angiotensin-converting enzyme (ACE) converts angiotensin 1 > angiotensin 2 - angiotensin 2: an active, restores fluid volume and BP - vasoconstriction causes raised BP - stimulates released of aldosterone by adrenals (which promotes Na+ and water reabsorption in the DCT and CT)

reproductive system

- reproduction : process by which new individuals of a species is produced - functions: passing genetic information but allow for diversity, continuation of species, based for evolution

active transport

- requires cellular energy - against the concentration gradient ( low to high) - transport in vesicles (endocytosis and exocytosis)

in what circumstances can the amount of oxygen available to be transferred onto haemoglobin drop?

- respiratory infection > pneumonia - pulmonary embolism (mismatch) - obstruction to the airways > COPD, asthma, bronchitis - emphysema > reduced respiratory membrane surface - high altitude > rarefied air E.G. Machu Pichu, Nepal, Lake Titicaca - decrease respiratory drive > drugs/alcohol, depresses respiration

veins

- return blood from the capillaries to heart - carry de-oxygenated blood (with one exception) - vein = into heart - thin, elastic muscular wall

superior vena cava (SVC) - towards head

- returns deoxygenated blood to the heart from the head, neck and arms - drains into the right atrium

inferior vena cava (IVC) - away from head

- returns deoxygenated blood to the heart from the rest of the body - drains into the right atrium

pulmonary circuit (RV>lungs>LA)

- right side of the heart pumps deoxygenated blood to the lungs - blood returned to right atrium via vena cava (from rest of the body) and coronary sinus (drains the heart) = oxygenated blood returned to the heart from the lungs via the 4 pulmonary veins - low pressure system = blood only travels short distance to lungs - right ventricle has much thinner walls than left ventricle

why is the heart muscle thicker on the left ventricle then the right?

- right ventricle only needs to pump blood a short distance to the lungs (low pressure needed for this) - left ventricle needs to pump blood around the entire body (higher pressure needed for this)

bursae

- sac-like structure - between skin & bone and ligament & bone - reduce friction

oil gland

- sebaceous gland (exocrine glands, sebum > oil > secretion, lubricates skin and hair)

exocrine glands

- secrete material via a duct into the lumen of an organ OR onto the free surface of the epithelium (E.G. sweat glands, salivary glands, mammary glands, pancreas, liver)

mucous cells

- secrete mucous + bicarbonate ions - protects stomach wall from damaging effects of stomach acid (HCL) - prominent in the gastric pit + neck of gastric glands

myokines

- secreted by contracting skeletal muscle with exercise - some have a role in chondrocyte survival - present in circulating blood - may increase in concentration around the muscle-joint complex with exercise due to increased muscle perfusion

pancreas endocrine system

- secretion of substances (electrolytes, proteins or enzymes) straight to a target site via ducts or tube - makes enzymes to aid in digestion delivered to the gut via the pancreatic duct - NB other examples include salivary glands, sweat glands and sebaceous glands

pancreas exocrine system

- secretion of substances into the blood stream - production of insulin and glucagon

small intestine mechanical digestion

- segmentation (local mixing of chyme with intestinal juices, repeated smooth muscle contraction & relaxation, sloshing back & forth) - peristalsis (weak movement, migrating motility complexes, propels chyme onwards through the tract)

accessory glands

- seminal vesicles: paired; found at base of bladder, empty into ejaculatory duct - prostate gland: encircles proximal urethra, below bladder, surrounds urethra and ejaculatory duct, can be felt during a rectal exam - bulbourethral glands: near bulb of penis, empty into penile urethra, lubricating fluid

broad functions of the nervous system

- sensation: collect and receive information, detect stimulation through receptors, pathway begins in organs > spinal cord > brain - integration: process and interpret sensory information, perception, personality, memory etc - motor commands: commands and instructions to body, begins in brain > spinal cord > organs

pleura

- serous membrane in two layers: (visceral pleura which adheres to then lung, parietal pleura lines the thoracic cavity) - filled with a thin film of fluid that 'sticks' the layers together - as the chest cavity pulls outward, and the lungs pull inward = create negative pressure = acts as a vacuum to keep lungs adherent to chest wall - ensures the lungs are expanded even at the end of forced expiration = otherwise they would collapse to ~5% of their normal size

why would you be less likely to fracture a sesamoid bone than a long bone?

- sesamoid bones don't provide support > they aren't exposed to the stress a long bone is - roundness allows them to distribute weight and stress

distal convoluted tubules

- simple cuboidal: secretion and absorption - no microvilli

endocardium (lines inner surfaces of heart chambers and valves)

- simple squamous endothelium - continuous with the great vessels

structure of the endothelium

- simple squamous endothelium (simple = single layer, squamous = cells are flattened 'fried egg' shape)

ribosome

- site of protein synthesis - location: produced in the nucleolus - structure: contains high content of RNA and associated proteins - function: ribosomes associated with endoplasmic reticulum synthesise proteins destined for insertion in the plasma membrane or secretion from the cell; free ribosomes synthesis proteins used in the cytosol.

frontal lobe

- sits at the front of the brain = rostral/anterior - personality - inhabitation of behaviours - executive functioning: attention, problem solving, planning, working memory - speech - movement (pre central gyrus = primary motor cortex, damage to different parts will correspond to weakness on the other side of the body in a particular part, motor homunculus)

hypothalamus

control centre

negative feedback mechanisms

control the secretion rates from the hypothalamus & pituitary

inhibition

decreased chance of AP

endocrine gland definition

ductless and release hormones into the surround fluid

cardiac cycle

each heartbeat results in ejection of blood from each ventricle into its artery (RV > pulmonary artery; LV > aorta)

in cortical nephrons

efferent arteriole delivers blood (peritubular capillaries): drain into small venules, carry blood to the venous system

rectum & anus function

eliminates faeces

satellite cell function

essentially act as the astrocytes for the dorsal root ganglia of the spinal cord - cell bodies carrying sensory information into the spinal cord in the PNS

seminal vesicles

function: secrete alkaline fluid neutralises vaginal acid, fructose for ATP production, prostaglandins stimulate sperm motility & viability, fibrinogen: coagulates semen after ejaculation, 60% of semen volume

urinary glucose levels

gluconeogenesis = synthesis of glucose from non-sugar precursors

as you grows taller, which part of your femur will produce the elongation?

growth plate (epiphyseal plate): made of hyaline cartilage (chondrocytes produce cartilage > causes head of bone to separate > ossifies > gets harder > continual), stops growing at around 25

tubuloglomerular mechanisms controls GFR

high GFR > rapid flow of filtrate in renal tubules > sensed by macula densa > paracrine secretion > constriction of afferent arteriole > reduced GFR

what stimulates the release of glucagon from the pancreas?

high levels of amino acid in the blood

meiosis

homologous chromosome > sister chromatids > crossing over can occur > meiosis 1 > meiosis 2 (= gametes)

pneumothorax

if air gets into the pleural space, the negative pressure is lost and the lung collapses

excitation

increased chance of AP

infertility

infertility is a reduced or lack of ability to conceive and carry a child, whether it be fortemporary or permanent reason

overview of the heart

- size: ~large fist - weight: males 280-340g; females 230-280g - function: pump blood to lungs and throughout body - heart is a muscle: made up of cardiac muscle (myocardium) - can contract repeatedly without becoming tired - right heart: pumps de-oxygenated blood to lungs - left heart: pumps oxygenated blood to rest of the body - divided into 4 chambers: atria (L, R), ventricles (L, R) - chambers separated by 4 valves - surrounded by pericardium (protective covering)

muscle regeneration

- skeletal muscle: fibres cannot divide after 1st year, growth is via enlargement of existing cells, repair (satellite cells and bone marrow produce some new cells, if not enough, fibrosis occurs most often) - cardiac muscle: cannot divide or regenerate, all healing done via fibrosis= scar formation - smooth muscle: regeneration is possible, cells can grow in size (hypertrophy), some cells (uterus) can divide (hyperplasia), new fibres can form from stem cells in blood vessel walls

muscularis externa

- skeletal muscle: voluntary control (mouth, pharynx, upper oesophagus & anus; control over swallowing & defecation) - smooth muscle: involuntary control (inner circular fibres & outer longitudinal fibres; mixes, crushes & propels food by peristalsis) - myenteric plexus (extensive parasympathetic & sympathetic innervation; cell bodies of the enteric nervous system; controls gut motility)

muscle types

- skeletal muscles - cardiac muscles - smooth muscles

co-ordinated action of muscle groups

- skeletal muscles function as combined groups to produce movement at a joint - muscles can be classified into 4 types based on their actions during joint movement: prime mover = agonist (produces most force, responsible for movement, i.e. biceps brachii contracts to flex elbow), antagonist (opposes prime mover, relaxes to allow prime mover complete control over joint action, i.e. triceps brachii relaxes to allow flexion of elbow), synergist (stabilises the nearly joint, prevents rotation, i.e. brachialis stabilises elbow during flexion), fixator (prevents movement of bone that prime mover is attached to, i.e. fixator muscles hold scapula tightly to axial skeleton prevents it from moving when elbow is flexed)

functions of testosterone

- skin: facial & body hair, hair pattern - brain: mood, sex drive - muscles: muscle mass and strength - reproductive system: erectile function, sperm production - bone marrow: red blood cell production

large intestine + rectum & anus mechanical digestion

- slow-moving haustral contraction - sluggish segmentation - peristalsis: slow - mass movement: strong waves force contents towards rectum 3-4 times per day

endocrine portion of pancreas

- small functional component - islets of langerhans - 4 distinct cells: alpha, beta, delta & C cells - release hormones to control blood sugar levels - beta cells: produce Insulin, stimulated by increase in blood sugar levels - alpha cells: produce glucagon - acini: dark clusters, 99% of gland - islets of langerhans: pale, 1% of gland

how does the muscularis layer differ between the oesophagus, stomach and small intestine?

- small intestine: muscularis externa (comprised of smooth muscle = inner circular and outer longitudinal in for the major movements of segmentation and peristalsis) - the stomach: has the addition of a third layer (oblique layer which facilitates the huge mixing waves that occur in the stomach to turn the swallowed food into chyme) - the oesophagus: comprised of skeletal (proximal 3rd) to control swallowing, with a combination of skeletal and smooth muscle in the middle 3rd, and smooth muscle in the distal 3rd

urinary blood ionic composition

- sodium (Na+) - potassium ions (K+) - calcium ions (Ca2+) - chloride ions (CI-) - phosphate ions (HP042-)

compact bone

- solid, hard layer of bone - location: diaphysis and at edges of bone - function: resists stresses produced by weight & movement (osteon = Haversian system = bone matrix deposited in rings around blood vessels, blood vessels run in Haversian canals, osteons aligned along lines of stress) (Volkmans canals - small channels in bone, transmit blood vessels from the periosteum into the bone, perpendicular to & communicate with Haversian canals) - lamellae: layers of bone - concentric lamellae: rings of bone - interstitial lamellae: old osteons that have been partially removed (osteocytes = found in spaces in bone matrix called lacunae, communicate with each other via spaces called canaliculi) - bone nutrition (osteocytes - trapped in lacunae within bone matrix, thus nutrients cannot diffuse through calcified matrix, osteocytes joined to each other and to blood via cell extensions within canaliculi which allow for diffusion of nutrients)

cell division

- somatic cell division = mitosis + cytokinesis (produces 2 daughter cells 46 chromosomes each) - reproductive cell division = meiosis (produces sex cells containing 23 chromosomes each)

valves of the heart

- specialised valves separate the heart chambers - control the direction of blood flow (like veins) - ensure blood moves in one direction - open and close in sequence - two valve types: atrioventricular (between atria and ventricles), and semilunar (between ventricles and aorta/pulmonary trunk)

spermatogenesis

- sperm production - the development of haploid spermatids > spermatozoa/sperm - involves: discarding excess cytoplasm and growing tails - location: inside tubules - time: ~9 weeks 1. appearance of acrosomal vesicle and flagellum in spermatid 2. growth of acrosome and flagellum 3. shedding of excess cytoplasm 4. mature sperm

spermatogenesis vs. spermiogenesis

- spermatogenesis is the entire process of sperm formation - spermiogenesis is just the maturation of round spermatids into elongated sperm

activation of spermatozoa

- spermatozoa released from testes are physically mature BUT immobile and incapable of fertilising an oocyte - other parts of male reproductive system aid in functional maturing and activation - capacitation: spermatozoa become > mobile when in contact with seminal gland secretions - capable of fertilisation when exposed to female reproductive tract

bundle of his

- stimulated by AV node - in the inter ventricular septum - signal travels to apex

growth hormone (GH)

- stimulates cell growth and reproduction by stimulating rate of protein synthesis - release regulated by: growth hormone-releasing hormone (GH-RH), growth hormone -inhibiting hormone (GH-IH) - the glucose-sparing action of GH is enhanced in the presence of glucocorticoids - 'a synergistic effect'

adrenocorticotropic hormone (ACTH)

- stimulates release of steroid hormones from adrenal cortex (specifically those that affects glucose metabolism) - released in response to corticotropin-releasing hormone (CRH) from hypothalamus

mast cells

- store chemical mediators of the inflammatory response

fat cells (adipocytes)

- store fat as a source of energy - insulation (hypodermis) - shock absorbers (palms, soles) - protective passing (kidney)

why is the oesophagus lined with stratified squamous epithelium?

- stratified (protection against abrasions, upper layer can be torn without exposing the underlying tissue)

why does stratified squamous keratinised, rather than stratified squamous non-keratinised epithelium covers the skin?

- stratified squamous keratinised epithelium forms a tough dry later in skin that minimises water loss via skin - stratified squamous non keratinised epithelium has a moist surface that would increase water loss across the skin because water can diffuse through it (SSNK is also more delicate, providing little protection against abrasion)

why does the epithelium lining the skin need to be keratinised stratified squamous?

- stratified squamous keratinised epithelium forms a tough dry layer (protection against abrasion, minimises water loss via skin)

UV protection

- stratum basale (melanocytes > produce melanin, melanin > released in granules or melanosome, in the stratum basale and stratum spinosum, protect DNA from UV damage)

skin colour

- stratum basale: melanocyte - epidermal cells - blood supply > red blood cells > red pigment haemoglobin (rise in temp > superficial vessels dilate, flushed and red, decrease in temperature > vessels contract, pale cyanosis)

epidermis (stratified squamous epithelium)

- stratum corneum (dead squamous cells - no nucleus, continually shed and regenerated) - squamous layer (squamous cells = keratinocytes, most abundant cell type, produces keratin > protein for strength, water resistance) - basal layer (single layer of columnar cells, melanocytes, site of mitosis)

endometrial layers

- stratum functionalis: superficial 2/3 of endometrium, spiral arteries, shed during menstrual phase of each cycle - stratum basaleo: reserve tissue for regeneration of stratum functionalis of subsequent cycles, straight arteries, retained during menstruation myometrium

cells

- structural and storage cells (fibroblasts, fat cells = adipocytes) - defence cells (macrophages, plasma cells, mast cells, leukocytes) - reserve cells (stem cells)

joint classification

- structural classification (SC): fibrous joints, cartilaginous joints, synovial joints - functional classification (FC): immovable, slightly moveable, freely moveable

tendons

- structure (attaches muscle to bone, parallel, closely packed arrays of collagen fibres, more stretchy than ligaments, tendon length determined by genetic predisposition) - function (mechanosensor, an anchor for the muscle, bears loading from muscle contraction to bone, transmits and modulates forces during locomotion) - clinical relevance: excessive mechanical loading > cause rupture or chronic tendinopathy insufficient loading > also has adverse effect on tendon tissue.

simple cuboidal epithelium

- structure (large cells, spherical nuclei) - location (lining of kidney tubules, small ducts in salivary glands, liver) - function (protection & absorption/secretion)

stratified squamous epithelium (cornified/keratinized)

- structure (layers of dead cells on surface, filled with keratin, tough, resistant to tearing) - location (skin - covers the surface of the body) - function (protective, almost water impermeable layer)

stratified squamous epithelium (non-cornified/non-keratinized)

- structure (nucleated cells in superficial layers, tough, upper layers of cells can be torn off without exposing the underlying tissues) - location (moist surfaces where tubular system open to the outside, lining of mouth, oesophagus, upper nostrils, anus, vagina) - function (protection)

pseudostratified columnar epithelium

- structure (nuclei at different levels but each cell attached to basement membrane) - location (lines upper respiratory tract) - function (filters air going to lungs, mucociliary-escalator, pathogens/dust stick to mucus and mowed upward and out by cilia)

transitional epithelium

- structure (stretched = looks like stratified squamous, relaxed = looks like stratified cuboidal) - location (lines ureters and bladder) - function (osmotic barrier, can stretch and relax)

simple columnar epithelium

- structure (tall columnar cells, microvilli present on surface of lining cells, increase surface area for efficient absorption) - location (stomach, intestines, oviducts lining) - function (absorption)

simple squamous epithelium

- structure (thin, smooth continuous lining) - location (cardiovascular & lymphatic vessel lining) - function (extensive diffusion, prevents blood from clotting, allows materials to pass through by diffusion and filtration and secretes lubricating substance)

urethra male

- structure: 20cm in length, internal urethral sphincter, external urethral sphincter - function: discharges (semen, urine) - prostatic urethra: passes through the prostate gland - membranous urethra: passes through the urogenital diaphragm - spongy (penile) urethra: passes through the length of the penis

regulation of blood volume and pressure

- structure: juxtaglomerular (JG) apparatus - senses changes in blood pressure and blood ion concentration > controls flow of blood to kidney and controls blood volume

bulbourethral glands

- structure: paired and pea-sized - location: inferior to the prostate on either side of the membranous urethra within the deep muscles of the perineum ducts open into the spongy urethra - function: secrete alkaline mucous, neutralises & lubricates urethra

cell membrane

- structure: phospholipid bilayer (fluid mosaic model), hydrophobic tail, hydrophilic head - function: protection and communication, ensure cells structural integrity, regulate entry/exit of substances into/out of the cell, participate in cellular communication, participate in some enzymatic activities, maintain chemical composition of cytoplasm, maintain chemical composition of extracellular fluid

protective layers of the brain

- subdural space: 'potential' space between meningeal layer of dura and the arachnoid - subarachnoid space: 'real' space between arachnoid and pia

sweat glands

- sudoriferous gland - apocrine gland (waxy secretion, associated with hair follicles, in densely hairy areas E.G. armpits, genital, nervous and hormonal control) - eccrine gland

great vessels of the heart

- superior vena cava (SVC) - inferior vena cava (IVC) - pulmonary trunk/pulmonary arteries - pulmonary veins - aorta - arteries = away - veins = in

the skeleton function

- support (rigid structural framework) - protection (enclose internal organs) - movement (anchor skeletal muscles) - mineral storage (homeostasis) - blood cell production (haemopoiesis) = red bone marrow - fat (energy storage) = yellow bone marrow

key roles of glial cells

- support: glia cells act as a physical support and protection for neurons, they also help keep the blood-brain barrier which prevents toxic chemicals in the blood from entering the brain - nutrition: glia cells help keep the environment around neurons in balance and makes sure the right nutrients are available for neurons - insulation: glia cells can create myelin, a fatty substance that helps insulate the axons of neurons, this helps keep electrical signals inside the neuron and helps them move faster - housekeeping: glia cells can prevent the build-up of toxic chemicals, help destroy viruses and bacteria, and get rid of dead neurons

respiratory membrane

- surface area (lots of it = surface area of alveoli make up almost the size of a tennis court) - concentration gradient (very high for O2) - size of particles (both O2 and CO2 are very small) - thickness of barrier (very thin: microns)

enterocytes

- tall columnar cells - oval nucleus in basal half of cell - apex contains micro-villi: protrusion of apical cytoplasm with actin core - absorb nutrients - secrete enzymes to aid in breakdown of macronutrients

process of mechanical digestion (up to the point of the stomach)

- teeth and tongue: mastication (physically breaking down food to form a bolus) - oesophagus: peristalsis and propulsion of bolus to stomach - stomach: muscularis externa (3 layers of multi-directional muscle providing a 'mixing wave' to create chyme, begins the process of chemical digestion)

what influences the rate of diffusion?

- temperature (higher temperature > diffuse faster) - surface area (larger surface > diffuse faster) - concentration gradient (higher gradient > diffuse faster) - size of particles (smaller particles > diffuse faster) - diffusion medium (solid > slowest, liquid > faster, gas > fastest) - thickness of barrier (thinner barrier > diffuse faster)

regulation within the endocrine system

- tertiary: due to hypothalamic regulation, both target organ and pituitary regulated - secondary: function of target gland altered by stimulating hormones or hormones released by pituitary gland - primary: originate in target gland, directly causes effect

glomerular filtration rate (GFR)

- the amount of filtrate formed in all the renal corpuscles of both kidneys each minute: is directly related to pressures that determine net filtration pressure, homeostasis requires kidneys to maintain a relatively constant GFR, normal value: 90 to 120mL/min/1.73 m2 - if GFR is too high: substances pass too quickly and are not reabsorbed - if GFR is too low: nearly all reabsorbed and some waste products are not adequately excreted

preload

- the amount of stretch experienced by the cardiac myocytes upon ventricular filling (how much blood is in the ventricle at the end of diastole) - preload is the end-diastole volume (EDV) - preload is increased in hypervolaemia, cardiac valve regurgitation, heart failure - more blood going into ventricles means MORE blood can be pumped out - myocardial stretch

ascending limb (water impermeable)

- the ascending thin segment: simple squamous epithelium - the ascending thick segment: simple cuboidal epithelium - impermeable to water - permeable to NaCl, salts reabsorbed

autonomic nervous system (ANS)

- the autonomic branch of the PNS can be further divided into two systems: the sympathetic nervous system 'fight or flight' (prepare to respond to a physical threat), the parasympathetic nervous system 'rest and digest' (unwind from heightened somatic activity)

voiding urine (micturition)

- the average person eliminates ~1500-3000mL urine/day - when 200mL urine in bladder > stretch receptors send signal to sacral spinal cord

how is breathing controlled?

- the brain closely monitors the levels of carbon dioxide rather than oxygen in the blood (rise of just 10% in arterial PCO2 causes respiratory rate to double, O2 levels need to drop below 60 mmHg before stimulating respiration) - if the levels of carbon dioxide get too high, the brain sends signals to the muscles that control breathing to increase the depth and rate of breathing

How is breathing controlled to respond to increased levels of CO2?

- the brain closely monitors the levels of carbon dioxide rather than oxygen within the blood (rise of just 10% in arterial PCO2 causes respiratory rate to double, O2 levels need to drop below 60 mmHg before stimulating respiration) - if the levels of carbon dioxide get too high the brain sends signals to the muscles that control breathing to increase the depth and rate of breathing.mostly passively controlled- (also active control possible) - respiratory centres included neurons in the medullary respiratory centre in the medulla + pontine respiratory group in the pons

5 + 6 overshoot & resting

- the cell is trying to regain its optimal internal environment - but, the response goes too far = too many K+ ions rush out - this makes the membrane potential become even more negative than the resting membrane potential = hyperpolarisation - the voltage-gated K+ and Na+ channels both close - the effects of the Na+/K+ ATPase is then seen again - membrane potential returns to resting. - Na+/K+ ATPase ACTIVE: working to pump 3 Na+ out, pulls only 2 K+ in - Na+ leakage channel OPEN: Na+ moving in down concentration gradient - K+ leakage channel OPEN: K+ moving in down concentration gradient - voltage-gated K+ and Na+ CLOSED

neurotransmitters

- the chemical signal released by one neuron that can exert an effect on a postsynaptic neuron across a synapse - neurotransmitters can be classified based on a number of factors - two ways to categorise them is based on: function (inhibitory & excitatory), mechanism (ionotropic & metabotropic)

sampling CSF

- the contents of the CSF can be tested for diagnosis of a range of neurological diseases - sampled via lumbar puncture ventricular drain - samples examined for: white blood cells (leukocytes = infection e.g. meningitis), red blood cells (erythrocytes = haemorrhage e.g. SAH), proteins (markers of disease), pressure (pressure can increase due to an obstruction e.g. hydrocephalus, injury e.g. TBI, brain tumour, meningitis etc)

below the cerebral cortex

- the cortex is the wrinkled part of the brain - it is where thinking, movement, language, perception occur - a number of structures beyond that have key function: thalamus, hypothalamus, cerebellum, brain stem

epithelial glands

- the demand for secretions requires the formation of masses of glandular epithelium below the surface - glands are formed from the invagination/infolding of epithelial cells - followed by subsequent growth in the underlying connective tissue

the action potential travels down the axon

- the depolarisation spreads to the adjacent segment of membrane i.e. Na+ moves into the axon through channels in each axon segment - this continues for the length of the axon until the signal reaches the axon terminal (C is for crawling) - jumps down the axon via the nodes of Ranvier = saltatory conduction (S is for speed)

descending limb (water permeable)

- the descending thick segment: simple cuboidal epithelium - the descending thin segment: simple squamous epithelium - important function in water conservation - freely permeable to water - not permeable to NaCl, increasingly concentrating filtrate

the membrane potential and action potentials

- the difference between charge inside and outside a cell = membrane potential - at 'rest', a neuron has fewer positive ions inside compared to outside - a stimulus can cause a temporary change in the membrane potential - if it becomes more and more positive, an action potential is initiated - an action potential is a wave of positive ions moving into a neuron that travels down the axon to the terminals - it is an all-or-nothing event (action potential = a neuron firing)

the graded potential

- the effect a neuron has will depend on the tissue it synapses on: neuron > neuron = action potential, neuron > muscles = contraction, neuron > gland = hormone secretion - not all stimulation will lead to an action potential - binding of neurotransmitter on the post-synaptic neuron triggers opening of ion channels > change in membrane potential locally = graded potential - graded potentials are not all-or-nothing - a larger graded potential will have a greater impact on whether an action potential occurs - small stimulus > no AP = no effect of the graded potential

electrical activity of the heart

- the heart generates own electrical rhythm - self-excitable, auto rhythmic - no neural or hormonal input - specialised pacemaker cells generate electrical activity = SA node (sinus rhythm, usually ~70-80bpm) - spreads throughout the heart via: AV node, internodal tracts, bundle of His, left/right bundle branches, Purkinje fibres

pituitary gland (hypophysis)

- the hypothalamus controls the activity of the pituitary gland (hypothesis) and the hormones it produces - major integrating link between the nervous & endocrine system - hormones that stimulate anterior pituitary are either releasing hormones or inhibiting hormones - regulatory hormones are delivered into the hypophyseal portal system for delivery into the anterior pituitary gland - posterior gland = hypothalamus regulates direct release of hormones by sensory and osmoreceptor stimulation. - pituitary gland is a small, oval gland found in a depression in the sphenoid bone - 9 peptide hormones are released by the pituitary (7 by the anterior, 2 by the posterior) - all 9: bind to membrane receptors, have a 2nd messenger system - anterior pituitary hormones: tropic hormones i.e. 'turn on' endocrine glands

urine incontinence

- the inability to control either urinary or bowel elimination and is abnormal after a person is toilet trained - causes: CNS injury (brain or spinal cord)

the synapse

- the junction between 2 neurons - axon terminal of neuron 1 contacts dendrite of axon 2 - where neurotransmitters are released and bound - many drugs used to treat disease modulate the activity at the synapse

function of the myelin

- the layers of lipid rich membrane wrapped around an axon act as insulation > increased speed of action potentials - amount of myelin and speed of APs, increases from birth to maturity - myelinated axons = saltatory conduction (S is for speedy) - unmyelinated axons = continuous conduction (C is for crawling): no nodes of Ranvier, AP has to occur along full length of axon - myelin plays a key role in health and disease - multiple sclerosis is a condition where myelin sheath around axons breaks down in CNS: believed to be immune-mediated, can be caused by genetic and environmental factors, slowing of APs, symptoms include blurred vision, muscle weakness, numbness, pain and depression - damaged myelin sheath > slow APs - intact myelin sheath > fast APs

synergistic/additive hormone

- the net result when to hormones have ADDITIVE effects is greater than the effect that each would produce acting alone - it ENHANCES the glucose-sparing action of GH in the presence of glucocorticoids

additive effects

- the net result when two hormones have additive effects is greater than the effect that each would produce acting along 'a synergistic effect' - E.G. the enhancement of the glucose-sparing action of GH in the presence of glucocorticoids

efferent and afferent pathway crossing

- the neurons that send sensory information from the body cross the midline (i.e. the neurons carrying sensory information from the left side of the body deliver axons to the right side of the brain) - the same crossing happens for vision coming in and motor information going out = contralateral pathways

mid-stream specimen

is a voided sample of urine considered sterile

excretion of wastes and nitrogenous wastes

kidneys get rid of organic waste products such as: urea: by-product of amino acid digestion, uric acid: by-product of RNA digestion, creatinine: by-product of creatine phosphate in muscles

myelin

l ayers of lipid-rich modified cell membrane. - produced by: oligodendrocyte in the CNS, Schwann cell in the PNS - membrane of these cells wraps around an axon > forms the myelin sheath - gaps between myelin = node of Ranvier - one Schwann cell > one segment of myelin on one axon - one oligodendrocyte > multiple segments of myelin on multiple axons

nuclear envelope

layer of two membranes that surrounds the nucleus of a cell

seminiferous tubules

leydig cells between tubules secrete testosterone

submucosa

loose connective tissue: contains blood vessels, glands & lymphatic tissue; submucosal (Meissner's) plexus = enteric nerve plexus, stimulates secretion from intestinal glands, absent in oesophagus & stomach

actions of glucagon

major catabolic hormone

flagella

moves an entire cell

cilia

moves fluids along a cell's surface

capillaries

permit diffusion between blood and interstitial fluids

haematopoiesis

process of formation of blood cells

mammary glands

produce milk that nourishes the newborn infant

gonads: ovaries

produce oocytes and hormones

bound ribosomes

produce proteins for insertion into the plasma membrane or export/secretion from the cell to be used elsewhere

free ribosomes

produce proteins used inside thecytosol of the cell

urinary blood cell formation

production of hormone erythropoietin

pharynx function

propels food from oral cavity to oesophagus

oesophagus function

propels food to the stomach

mitosis

prophase > metaphase > anaphase > telophase > cytokinesis > G1 (centrioles replicate) > S (DNA replication) > G2 (final growth and activity before mitosis)

exocytosis

proteins, lipids and other products produced in the cell are packages into vesicles by the Golgi apparatus

homeostasis of blood electrolyte levels

reabsorption and secretion of ions by kidney tubules (conservation of HCO3-, secretion of H+)

dendrites

receive chemical messages from other neurons

gonadotropins (regulate gonadal activities)

released in response to gonadotropin-releasing hormone (GnRH) from hypothalamus

path of blood flow in kidneys

renal artery > segmental arteries > interlobar arteries > arcuate arteries > interlobular arteries > afferent arterioles > glomerular capillaries > efferent arterioles > peritubular capillaries > interlobular veins > renal veins

renal vascularisation

renal artery > segmental artery > interlobar artery > arcuate artery > cortical radiate arteries > afferent arterioles > glomerus to efferent arterioles to capillaries of the nephron > cortical radiate veins > arcuate vein > interlobar vein > renal vein

urinary blood pressure

renin production

Schwann cell

sheet wrapped around axon

satellite cell

small, flattened cells

astrocyte

star shaped

musculoskeletal system

supports and movement

bowman's capsule

surrounds the glomerulus, collects filtrate, connected to proximal convoluted tubule

gene expression

symbiosis of a specific protein requires transcription of a gene's DNA into RNA and translation of RNA into a corresponding sequence of amino acids

smooth ER

synthesises fatty acids and steroids, such as oestrogen and testosterones; inactivates or detoxifies drugs and other potentially harmful substances; removes the phosphate group from glucose-6-phosphate; and stores and releases calcium ions that trigger contraction in muscle cells

rough ER

synthesises glycoproteins and phospholipids that are transferred into cellular organelles, inserted into the plasma membrane, or secreted during exocytosis

blood flow of the heart

the amount of blood passing through a tissue in a given time (mL/min) - perfusion = rate of blood flow per given mass of tissue (mL/min/g) - important for delivery of nutrients & oxygen, and removal of metabolic wastes - rate of flow within the closed cardiovascular system is determined by: pressure in the system, resistance (forces opposing blood flow)

blood pressure (BP)

- the pressure the circulating blood exerts on the walls of the blood vessels - expressed as arterial systolic pressure over diastolic pressure in millimetres of mercury (mmHg) - normal resting BP = 120/80mmHg (low BP = hypotension, high BP = hypertension) - must be closely regulated: high enough to ensure sufficient driving pressure for propelling blood to the tissues, but not so high that it creates extra work for the heart and causes vessel damage - systolic pressure (120mmHg): highest pressure in systemic arteries (peak in aorta), during ventricular systole (mid-ejection phase) - diastolic pressure (80mmHg): lowest arterial pressure, during ventricular diastole (just before aortic valve opens)

afterload

- the pressure which the ventricle must overcome in order to eject blood from the ventricle (force required to open semilunar valves) - LV must overcome arterial pressure to open SL valves and pump blood into the aorta/pulmonary arteries - only when ventricular pressure is greater than arterial pressure can SL valves open and ventricles pump blood out of heart - afterload is increased in hypertension (systemic, pulmonary), vasocontraction = less outflow time = more blood remains in ventricle after systole, increased resistance means LESS blood can be pumped out - arterial pressure

spermiation

- the release of a sperm cell from a sertoli (also known as sustenticular/nurse) cell - loss attachment to sertoli cells - enters lumen of seminiferous tubules

scrotum internally

- the scrotal septum: divides the scrotum into two sacs (each containing a testis) - subcutaneous layer and muscle tissue (dartos muscle) - cremaster muscle (suspender): associated with each testis in the scrotum, small bands of skeletal muscle, descend as an extension of the internal oblique muscle > through the spermatic cord to surround the testes - dartos muscle (skinned): in the of the scrotum, bundles of smooth muscle fibres, also in the subcutaneous layer of the scrotum

the filtration membrane

- the size of the endothelial fenestrations and filtration slits have been exaggerated for emphasis - during glomerular filtration, water and solutes pass from blood plasma into the capsular space - three key parts: 1. fenestrated (pores) capillary o endothelium blocks blood cells & platelets 2. basal lamina = thick glomerulus basement membrane (restricts large proteins & some organic anions) 3. slit membrane between pedicels (forms by diaphragms between pedicels of the podocytes, restricts some medium proteins & organic anions)

haemodynamic

- the study of blood flow through the circulation - blood flow is determined by: how much blood the heart pumps out, the pressure that the blood is under, the resistance that blood encounters in the vessels - status of blood flow in the circulation = net result of cardiac output and vascular resistance to flow

why can a lung collapse?

- there may be some air or fluid get into the pleural space - the negative pressure is lost so air can't flow into the lung > lung collapse

what would be the result of losing villi in the small intestine?

- there would be a loss of surface area for nutrient absorption - the villi and microvilli increase the surface area of the small intestine by 60-120 times - the loss of microvilli also results in the loss if enzymes produced by the brush border that help to digest carbohydrates and protein

ventricles (pumping chambers)

- thick walls (especially left) - active pumping

lamina propria

- thin layer of loose connective tissue - contains BV, nerves & lymphatic tissue - mucosa-associated lymphatic tissue (MALT): protection against infection - route by which nutrients are absorbed - supports epithelium

muscularis mucosae

- thin layers of smooth muscle - cause folds to form in the mucosal layer - increases local movements increasing absorption of nutrients with exposure to 'new' surface

atria (receiving chamber)

- thin walls - passive filling

direct communication definition

- through gap junctions - usually limited to adjacent cells

how does the normal stomach uniquely adapt to protect itself from its harsh environment?

- tight junctions found on the lateral surfaces of the epithelial cells to prevent the acid from seeping through into the underlying lamina propria - mucous neck and mucous surface cells which secrete very thick mucous (up to 3mm thick which protects the epithelial cells) - the cells of the stomach have a very fast turnover rate so any damaged cells are quickly sloughed off

parietal lobe

- top of the head = dorsal/superior, posterior/caudal to frontal love: touch, body awareness, taste, perception, making sense of the world - sensation: post central gyrus = primary somatosensory cortex, damage to different parts will correspond to lack of sensation on the outer side of the body in a particular part, sensory homunculus

mucosa epithelium (depends on the location)

- transitional epithelium at the proximal end (near the bladder) - stratified and pseudostratified columnar: mid urethra (in males) - stratified squamous epithelium at the distal end (near the urethral opening)

mechanisms of intercellular communication: endocrine

- transmission: through the bloodstream - chemical mediators: hormones - distribution of effects: target cells are primarily in other tissues and organs and must have appropriate receptors

haemoglobin (Hb) structure

- transportation of O2 and CO2 - quaternary protein complex (4 parts - 2x alpha globin chains, 2 x beta globin chains) - each chain contains a single heme - each heme group has an iron at centre (this is the location where O2 and CO2 bind) - two Hb states depending on O2 binding (oxy-Hb = bound to O2 > bright red, deoxy-Hb = not bound to O2 > deep red purple)

reproductive system in clinical practices

- tubal ligation is ligation of uterine tube in the sterilisation procedure - an ectopic (outside the uterus) pregnancy within the uterine/fallopian tube is an emergency situation, endangering the life of the mother - in this situation, the fertilised ovum becomes lodged in the oviduct; this can lead to rupture and haemorrhage - pap smear is obtained from cervical region

bipolar

- two branches from cell body - one acts as the dendrite - the other acts as the axon - rare, e.g. in the retina

multipolar

- two or more dendritic branches - one axon - most common in CNS

target glucose levels for diabetics

- type 1 diabetes (target levels 4-8mmol/L before meals, <10mmol/L two hours after starting meals) - type 2 diabetes (target levels 6-8mmol/L before meals, 6-10mmol/L two hours after starting meals) - people with type 2 diabetes who are not taking sulphonylurea medication or insulin could aim for a blood glucose as close to normal as possible - risk of hypoglycaemia for both type 1 and type 2 (low blood glucose) - less than 4mmol/L if insulin or certain types of tablets are used, but does not apply to all tablets or for people who do not take any tablets for diabetes - check with doctor to see what applies personally

blood

- type of connective tissue - 3 key components: cells (red blood cells = erythrocytes, white blood cells = leukocytes, platelets = cell fragments), fibres (fibrinogen > fibrin = when clotting cascade activated), fluids (plasma = fluid and solutes, E.G. proteins and electrolytes)

gallbladder bile secretion

- under control of: neural activation, hormones (CCL & secretin) and bile salts 1. vagus nerve stimulation causes gallbladder contraction releasing bile into the duodenum 2. cholecystokinin (produced by the duodenum) is carried through the circulation to the gallbladder and stimulates the gallbladder to contract and the sphincters to relax, releasing bile into the duodenum 3. secretin (produced by the duodenum) is carried through the circulation to the liver and stimulates bile secretion by the liver 4. bile salts also stimulate bile secretion, over 90% of bile salts are reabsorbed in the ileum and are returned to the liver where they stimulate additional secretion of bile salts

white matter of the brain contains

- underneath the gray matter of the cortex - mainly myelinated axons that project: within a hemisphere, between hemispheres, into the brain, out of the brain - association fibres: connect parts of the same hemisphere, E.G. gyrus to gyrus, lobe to lobe - commissural fibres: connects the two hemispheres, E.G. corpus callosum - projection fibres: project out of the brain to the spinal cord or into the brain

appendicular skeleton

- upper & lower limbs - pelvic & pectoral girdles - 126 bones

waterproof

- upper epidermis (keratin, tough water-proof protein barrier, phospholipid matrix > the skin's main waterproofing agent)

oesophagus sphincters

- upper oesophageal sphincter: skeletal muscle, junction of pharynx & oesophagus, prevents entrance of air into oesophagus - lower oesophageal sphincter: at gastro-oesophageal junction, relaxed = allow food to enter stomach, rest = prevents reflux of acidic gastric contents

urine storage and elimination

- ureter: macroscopic (~25 cm long) - structure: 2 ureters, renal pelvis of one kidney > bladder, no anatomical valve at the opening of the ureter into bladder > when bladder fills it compresses the opening and prevents back flow - function: transports urine renal pelvis of one kidney > bladder - peristaltic waves hydrostatic pressure gravity move urine

excretion of waste & assessment of kidney function

- urinalysis: analysis of the volume and physical, chemical, and microscopic properties of urine, blood tests for kidney function (e.g. blood urea nitrogen = BUN = measures blood nitrogen that is part of the urea resulting from catabolism and deamination of amino acids, serum creatinine results from catabolism of creatine phosphate in skeletal muscle, GFR) - renal plasma clearance: volume of blood cleared of substance per unit time

oliguria

- urine output less than 400mL per 24 hours, indicates inadequate elimination of urine - residual urine, or more than 50mL of urine that remains in the bladder after voiding - causes: acute kidney injury, chronic kidney disease

passive transport

- uses own energy: diffusion (simple or facilitated), osmosis

female reproductive tract

- uterine tubes (oviducts, fallopian): normal site for fertilisation, deliver an oocyte or embryo to the uterus - uterus: site of embryonic and fetal development, exchange between maternal & fetal bloodstream - vagina: birth canal during delivery, site of sperm deposition, passageway for fluids during menstruation

veins and venules

- venules > veins - drain capillary network - increasing diameter (from venules > veins) - thinner walls - lower blood pressure ~10mmHg, little change - high capacitance and can expand easily (blood reservoir = contain ~70% of blood volume, large veins can accommodate larger changes in volume) - contain values (comprised of folds in the intima that overlap, prevent the back flow of blood)

occipital lobe

- very back of the brain = posterior/caudal - vision - early stages of interpreting visual information - left gets information from left visual field, right from right

stroke volume (SV)

- volume ejected per beat from each ventricle, ~70mL - SV = EDV - ESV

chemical classes of hormones

- water soluble - lipid soluble

regulation of blood pressure

- what happens if MABP is too low: blood flow to tissues is not adequate, non-delivery of nutrients, oxygen etc. and non-removal of metabolic wastes > homeostasis is not achieved - what happens if MABP is too high: tissue damage, in particular heart & blood vessel damage occurs - blood pressure regulated by two negative feedback loops: baroreceptor reflex, chemoreceptor reflex

antagonistic hormone

- when 2 antagonistic hormones interact, the observed effects are weaker than those produce by either hormone acting unopposed - PTH and calcitonin - insulin and glucagon - insulin > allows body to use sugar (e.g take in glucose) - glucagon > released at low blood sugar> liver and muscle cells to change stored glycogen back to glucose

if a patient is hyperventilating what may be the concern?

- when the rate and depth of respiration exceed demands for oxygen delivery and carbon dioxide removal = leads to hypocapnia - hypocapnia (low levels of CO2, can cause transient loss of consciousness, the alveoli and capillaries in the lungs exchange oxygen for carbon dioxide, imbalances in the exchange of these gases can lead to dangerous respiratory disorders, such as respiratory acidosis or hyperventilation)

antagonistic effects

- when two antagonistic (opposing) hormones interact, the observed effects are weaker than those produced by either hormone acting unopposed - E.G. PTH and calcitonin, or insulin and glucagon

bone modelling vs. remodelling

- when: modelling - during growth, remodelling - throughout life - how: osteoclasts resorption of bone, osteoblasts formation of bone, E.G. distal femur remade every 4 months

nucleolus

- where ribosomes assemble - site of rRNA synthesis - obvious in cells that are actively synthesising protein (e.g. liver, nerve, muscle)

formation of bone: ossification

- where: intramembranous ossification formation of flat bones, or endochondral ossification mainly occurs during cortical long bone development - when: begins in early embryonic life - how: intramembranous ossification (bone forms form connective tissue, mesenchymal cells > bone forming cells), endochondral ossification (bone forms from hyaline cartilage)

interstitial: bone growth in length

- where: occurs 'within' bone, occurs at epiphyseal plate - how: hyaline cartilage gradually becomes bone. process similar to endochondral ossification - when: birth until 18-25 years, after this (cartilage cells stop dividing, cartilage is replaced by bone, bone stops growing in length) - how does bone grow from cartilage at epiphyseal plate?: zone 1: cartilage cells appear normal, zone 2: cartilage cells rapidly proliferate, zone 3: cartilage cells enlarge, zone 4: cartilage cells burst, cartilage matrix becomes calcified - osteoclasts enter & remove cartilage matrix - osteoblasts enter & create new bone matrix

position of the heart

- within thoracic cavity - anterior portion of the mediastinum - left of mid-sagittal plane - lies within pericardial sac. - base of heart at superior surface, posterior to sternum at level of 3rd costal cartilage - apex = inferior pointed tip of heart; in 5th intercostal space approx. 7.5cm to left of midline. - height of heart ~ 12.5cm from base to apex.

prolactin (PRL)

- works with other hormones to stimulates mammary gland development and milk production - released in response to several prolactin-releasing factors (PRH) - inhibited by prolactin-inhibiting hormone (PIH)

distribution of body fluid

- young adult females = 50% - young adult males = 60% - babies = 75% - elderly = 45%

liver

- ~1.4kg - below diaphragm, right of the stomach - right lobe is larger - size causes right kidney to be lower than the left - falciform ligament: separates the liver from the diaphragm & anterior abdominal wall

why is the small intestine lined with simple columnar epithelium?

-simple layer (easier absorption through 1 layer, columnar rather than squamous > basic protection) - microvilli (increase surface area for absorption)

testicular veins & pampiniform plexus

-structure: network of small veins, in the male spermatic cord, formed by the union of multiple spermatic veins from the back of the testis and tributaries from the epididymis - function: regulates testicular temperature

functions of the CSF

1. mechanical protection: protects brain from hitting the skull, suspends brain so not sitting on base of skull 2. chemical protection: controls fluid around neurons and glia, removes wastes 3. nourishment: course of oxygen and glucose 4. regulation: contributes to homeostasis, route for chemicals to get distributed through the CNS

renal sinus and sinus drainage

1. minor calyces 2. major calyces 3. renal pelvis 4. ureter

function to recaptures NaCI returns it to renal medulla

1. more salt is continually added by the PCT 2. the higher the osmolarity of the ECF, the more water leaves the descending limb by osmosis 3. the more water that leaves the descending limb, the saltier the fluid is that remains in the tubule 4. the saltier the fluid in the ascending limb, the more salt the tubule pumps into the ECF 5. the more salt that is pumped out of the ascending limb, the saltier the ECF is in the renal medulla

pancreas exocrine

1. parasympathetic stimulation from the vagus nerve causes pancreas to release a secretion rich in digestive enzymes 2. secretin released from the duodenum stimulates the pancreas to release a watery secretion rich in bicarbonate ions 3. cholecystokinin (CCK) released from the duodenum causes the pancreas to release a secretion rich in digestive enzymes

functions of vagina

1. passageway for menstrual fluids 2. receives penis and temporarily holds spermatozoa 3. forms inferior portion of birth canal

synthesis, secretion and discharge of protein from a cell

1. proteins are synthesised at ribosomes on rough endoplasmic reticulum 2. proteins pass within a transport vesicle to the Golgi apparatus 3. proteins accumulate and are modified, sorted and packaged in the Golgi apparatus 4. vesicles containing proteins pinch off of the Golgi apparatus to form secretory vesicles 5. secretory vesicles move toward the cell surface 6. vesicle contents are discharged from the cell via exocytosis

respiratory system function

1. provides for gas exchange 2. helps regulate blood pH 3. contains receptors for sense of smell, filters inspired air, produces vocal sounds (phonation), and excretes small amounts of water and heat

integumentary system

1. regulates body temperature 2. stores blood 3. protects body from external environment 4. detects cutaneous sensations 5. excretes and absorbs sensations 6. synthesises vitamin D

the phases of an action potential

1. resting membrane potential 2. stimuli and threshold 3. depolarisation 4. repolarisation 5. overshoot 6. resting

summary of the action potential

1. resting membrane potential: Na+/K+ ATPase active, Na+ channels closed 2. stimuli and threshold 3. depolarisation: Na+ channels open 4. repolarisation: Na+ channels open, K+ channels open 5. overshoot: Na+/K+ ATPase active 6. resting: Na+/K+ ATPase active

blood flow

1. right atrium (deoxygenated blood) - tricuspid valve 2. right ventricle - pulmonary valve 3. pulmonary trunk and pulmonary arteries 4. in pulmonary capillaries, blood loses CO2 and gains O2 5. pulmonary veins (oxygenated blood) 6. left atrium - bicuspid valve 7. left ventricle - aortic valve 8. aorta and systemic arteries 9. in systemic capillaries, blood loses O2 and gains CO2 10. superior vena cava, inferior vena cava, coronary sinus

physical brain protection

1. skull 2. meninges: 3 layers of connective tissue; dura, arachnoid and pia; partition brain via dural folds 3. cerebrospinal fluid

mechanisms of cough

1. stimulation of mechanoreceptors or chemoreceptors (throat, respiratory passages or stretch receptors in lungs) 2. afferent impulses to cough centre (medulla) 3. efferent impulses via parasympathetic & motor nerves to diaphragm, intercostal muscles & lung 4. increased concentration of diagrammatic, abdominal & intercostal (ribs) muscles = noisy expiration (cough)

negative feedback

1. stimulus alters controlled condition 2. receptors detect change 3. input sent to control centres for evaluation 4. commands sent to effector to reverse response

neural control of micturition

1. stretch receptors detect filling of bladder, transmit afferent signals to spinal cord 2. signals return to bladder from spinal cord segments S2 and S3 via parasympathetic fibres in pelvic nerve 3. efferent signals excite detrusor muscle 4. efferent signals relax internal urethral sphincter; urine is involuntarily voided if not inhibited by brain 5. for voluntary control, micturition centre in pons receives signals from stretch receptors 6. if it is timely to urinate, pons return signals to spinal interneurons that excite detrusor and relax internal urethral sphincter; urine is voided 7. if it is untimely to urinate, signals from pons excite spinal interneurons that keep external urethral sphincter contracted; urine is retained in bladder 8. if it is timely to urinate, signals from pons cease and external urethral sphincter relaxes; urine is voided

general functions of blood (maintenance of homeostasis)

1. transport dissolved gases nutrients, hormones and metabolic wastes. 2. regulation the pH and ion composition of interstitial fluids. 3. restrict fluid losses at injury site. 4. defend against toxins and pathogens. 5. stabilise body temperature.

layers of the heart tissue

3 layers: pericardium, myocardium, endocardium

structure of the heart

4 chambers (right atrium, right ventricle, left atrium, left ventricle)

breathing

the method by which the human body exchanges oxygen from the environment with carbon dioxide within the body

lungs

the organs that are responsible for the exchange of these gases

how does the oral contraceptive pill prevent pregnancy?

the pill releases low levels of these hormones so that: production of her hormones (endogenous) hormone is 'switched off' to prevent ovulation, sperm is blocked due to the thickening the mucus made by the cervix, changes occur in the lining of the uterus to make it unsuitable for a fertilised ova to stick

scrotum externally

the scrotum looks like a single pouch of skin separated into lateral portions by a median ridge called the raphe

respiratory system structure

the upper respiratory system includes the nose, nasal cavity, pharynx, and associated structures; the lower respiratory system includes the larynx, trachea, bronchi, and lungs

vasectomy

the vas deferens are ligated, cut or cauterised hence secretions from testes (spermatozoa) and epididymis prevented from release.

what is the normal volume of air inhaled and exhaled during normal quiet breathing?

tidal volume

end diastolic volume (EDV)

volume in ventricle at end of diastole (after filling), ~130mL

end systolic volume (ESV)

volume in ventricle at end of systole (after ejection into artery), ~40-50mL

urinary waste and foreign substances

waste-urea, uric acid, creatinine

how does a water-soluble hormone activates a target cell?

water soluble hormones cannot cross the plasma membrane, therefore it must bind to receptors on the cell surface, triggering 1st and 2nd messenger cascades within the cell to initiate a response

fracture healing

when to and not to immobilise

ligand-gated ion channel

will open and close in response to a chemical message binding to the channel

voltage-gated ion channels

will open and close in response to a specific voltage, or difference in charge across a membrane

why do we have a residual volume?

· important to keep lungs semi-inflated to increase compliance = expandability - compliance = measure of the ability of the lungs to stretch and expand. - a decrease in compliance impairs the ability of lungs to expand and impairs alveolar ventilation > greater pneumatic tension (surfactant reduces tension)

(SC) synovial joints

· joint cavity · most freely moveable, E.G. Shoulder, hip, knee

what happens when your bladder has reached 200mL but you are not ready (or it is not convenient) to urinate?

- at ~200mL the detrusor muscle begins to contract AND the internal urethral sphincter muscle begins to relax - this sends signals through the nervous system and creates the "urge" to urinate - at ~500mL the detrusor muscle contractions begin to force open the internal urethral sphincter - unless the external urethral sphincter is powerful enough to prevent it, micturition (urination) will occur involuntarily (incontinence) - sympathetic nervous system regulate the process of urine storage in bladder > once bladder is filled with urine (200ml) stretch receptors in bladder wall distort with an urge to urinate > afferent fibres in pelvic nerve carry information to sacral spinal cord > parasympathetic pre ganglionic fibre carry motor commands back to bladder > post ganglionic fibres stimulate detrusor muscle contraction increasing hydrostatic pressure in bladder > if urination is not done the increases hydrostatic pressure forces external sphincter to open and urine is leaked involuntary (at 500ml)

what is the difference between atrioventricular and semilunar valves?

- atrioventricular valves: between the atrium and the ventricles, attach to the wall of the heart via chordae tendina, open/close via papillary muscles, includes the tricuspid valve and bicuspid valve - semilunar valves: allow blood to flow from the ventricle to the aorta or ventricle to the pulmonary artery, they open and close in response to pressure, includes the aortic valve and pulmonary valve

what characteristics of cardiac pacemaker cells assist in their ability to contract cardiac muscle?

- automaticity: ability to generate action potential automatically without requiring commands from the nervous system - conductivity: ability to pass the action potential onto the next cardiac cell

innervation of the heart (automatic control)

- autonomic nervous system provides input to the heart - nervous input at SA node and AV node - purpose of nervous regulation: maintain blood flow to vital tissues, achieved by influencing heart rate and force of contraction > alter output from heart - base heart rate set by pacemaker cells (SA node) - can be altered by nervous system input (base heart rate is ~100bpm, BUT kept lower than this by constant inhibitory control at rest) - two divisions of the autonomic system (parasympathetic, sympathetic)

baroreceptor reflex

- baroreceptors present in carotid sinus and aortic arch - detect and respond to changes in blood pressure - E.G. when blood pressure is low (vessels are not stretched, signals blood pressure is low, signals to the medulla to alter nervous system activity) - increase sympathetic nervous activity (increases HR and ventricle contractility > Increases SV > increases CO, vasoconstriction > increases TPR > increases MAP) - decrease parasympathetic nervous system activity (increases HR > increases CO, vasoconstriction > increases TPR = only in a few areas > increases MAP) - the opposite response will be stimulated in response to elevated BP

actions of triiodothyronine (T3), thyroxine (T4)

- basal metabolism - carbohydrate, lipid & protein metabolism - heart - nervous system - musculoskeletal - reproductive

presynpatic neuron

- before the synapse - neuron 1 - the one contributing the axon terminals - releasing NT

temporal lobe

- behind the ears = inferior/ventral to frontal lobe. - hearing - recognition of objects - memory - emotion - understanding language

increased glucose

- beta cells secrete insulin (increase glucose uptake, glucagon synthesis = glycogenesis, increase amino acid uptake and protein synthesis, increase uptake of fatty acids, decrease amino acid release) - adipose tissue (increase glucose uptake, increase uptake of fatty acid, decrease lipolysis-fat breakdown to free fatty acids) - liver (increase glucose = not require oxygen, increase glucose synthesis = glycogenesis, decrease glycogen breakdown = glycogenolysis, decrease ketone release)

bile canaliculi

- between adjacent hepatocytes - accumulate bile produced by hepatocytes - unite to form right & left hepatic ducts

hepatic sinusoids

- between strands of hepatocytes - blood filled channels - blood filters through sinusoids (nutrient absorption, secretion of products, breakdown of products, phagocytosis: Kupffer cells)

erythrocyte structure

- biconcave disc (approx. 2um thick and 7.5um long) - no nucleus (anucleate, don't grow or divide) - no organelles (except for cytoskeleton, don't make new proteins) - packed with haemoglobin (transports O2 to tissues, transports CO2 away from tissues)

portal triad

- bile duct - branch of hepatic artery - branch of hepatic portal vein

gallbladder physiology

- bile is continuously secreted by the liver (~1L per day) - gallbladder can hold 30-70mL of bile at a time - bile modification: water is absorbed, biles salts become concentrated - gallstones: excessive saturation & concentration of bile, crystals form = gallstones

flow of bile

- bile produced by hepatocytes - bile canaliculi are initial part of the bile duct system - tight junctions seal the edges of the canaliculi - from bile canaliculi, bile empties into bile ducts (found at periphery of lobules: portal triad) - merge into right & left hepatic ducts - unite & exit liver as common hepatic duct 1. hepatocytes secrete bile into bile canaliculi 2. bile canaliculi flows into bile ducts of portal triads 3. bile ducts flow into left & right hepatic ducts 4. left & right hepatic ducts drain into common hepatic duct 5. common hepatic duct unites within cystic duct = common bile duct - not all bile runs directly from liver to small intestine - 50% stored in gallbladder - cystic duct unites with common hepatic duct = common bile duct - right & left haptic ducts unite to form common hepatic duct: carries bile OUT of liver - cystic duct from gallbladder: carries bile to from gallbladder - common bile duct = common hepatic duct + cystic duct (empties bile into duodenum)

dense regular CT

- binds bones together and attaches muscles to bone - transfers force form muscles to bone - in the tendons and ligaments

haemorrhage

- bleeding from damaged vessel - internal vs external - usually refers to massive blood loss - hypovolaemia = massive decrease in blood volume > hypovolaemic shock - 10-15% loss can be tolerated without serious medical complications - blood donation 8-10% volume - requires urgent haemostasis to control bleeding and stem blood loss

water regulation by kidney in cooperation with ADH

- cells in the kidneys and hypothalamus are active monitors - regulation is performed by: antidiuretic hormone (prevents excessive water loss in urine, acts on DCT and collecting tubules), aldosterone (regulates sodium ion content of extracellular fluid, acts on DCT and collecting tubules, triggered by the renin-angiotensin mechanism) - dilute urine is produced if water intake is excessive - less urine (more concentrated) is produced if large amounts of water are lost 1. heat causes water loss and dehydration 2. receptors in the hypothalamus detect the low water content of blood and signal the posterior pituitary 3. the posterior pituitary releases ADH into the bloodstream 4. ADH increases the permeability of the distal tubule and the collecting duct, allowing more water to be reabsorbed into the blood 5. water is retained in body and concentrated urine is produced

grey matter in the brain

- cerebral cortex: outermost layer of the brain, 6 layers of neurons - basal ganglia: collections of deep nuclei within the cerebrum - thalamus: paired masses of grey matter either side of the midline

2. stimuli and threshold

- certain chemical messages can cause ligand-gated Na+ ion channels to open - Na+ then rushes into the neuron, making it less negative - if the stimulus is strong enough to move membrane potential above threshold, an action potential will occur (depolarisation = membrane potential moves closer to zero, threshold = -55 to -50 mV) - there is no return: once a neuron reaches threshold an action potential will occur - if threshold isn't reached, failed initiation

microglia function

- changes from ramified to ameboid shape when damaging stimuli are detected - mobile cells, continually survey the CNS - migrates to dangerous material and phagocytoses it - macrophages of the CNS

effects of smoking

- chemical irritants in cigarettes initially slow the movement of cilia, eventually cilia are destroyed - loss of cilia causes mucus to pool (i.e. become trapped) = hence a smoker's cough develops to help with the removal of mucus - respiratory epithelium is replaced by stratified squamous epithelium - cells in this stratified epithelium can become cancerous (i.e. start dividing uncontrollably), forming a tumour - shortness of breath usually results from a blockage to the flow of air in part of the lung = E.G mucus buildup or tumour

hormone

- chemical mediator that helps maintain homeostasis - they travel in your bloodstream to tissues or organs

chemoreceptor reflex

- chemoreceptors present in aortic arch - detect changes in composition of the blood - increase activity when O2 low, CO2 high, H+ high (low pH) signals to the medulla (brainstem) to: increase sympathetic nervous activity (increase HR and ventricle contractility > increases SV > increases CO, vasoconstriction > increases TPR > increases MAP), decrease parasympathetic nervous activity (increase HR > increase CO, vasoconstriction > Increases TPR = only in a few areas > increases MAP

AV valve attachment to walls of the heart

- chordinae tendineae (cord-like tendons, 'heart strings', made up of collagens, elastin, connect AV valves to papillary muscles) - papillary muscles (papillary muscles connect to heart wall, contract when ventricle contracts, pulls on chordinae > valves pulled closed, prevents AV valves from everting blood into atria = regurgitation, ruptured muscle = i.e. post-heart attack) > dysfunction of the valve > change in blood flow)

chromosomes

- chromosome pair 1-22 (autosomes) - chromosome pair 23 (sex chromosome) - the X and Y chromosome are the sex chromosomes - female XX - male XY

small intestine histological structure

- circular folds (pilca circulare): deep 1cm tall folds within mucosa & submucosa, NOT found in lower ileum, cannot stretch like rugae., important for absorption - villi: ~1mm tall, increases surface area of epithelium, contains vascular capillaries, contains lacteals (lymphatic capillaries) - micro-villi: cell surface feature, brush border, ~1um, increases surface area for absorption, enzymes bound to complete digestion, chemical digestion: the brush border plasma membrane contains integral proteins that function as enzymes to complete digestion of carbohydrates and protein, (enterokinase: activates trypsin = protease, disaccharidases: digest disaccharides to monosaccharides, aminopeptidases: digest small peptide fragments into amino acids) - mucosal-associated lymphoid tissue (MALT): lamina propria of distal ileum, prevent bacteria from entering blood stream

blood typing

- classification based on presence/absence of inherited antigenic substances on the surface of red blood cells - 4 types: A, B, AB, O - the letter refers to the type of molecules expressed on the rbc surface - positive or negative: refers to the presence/absence of Rhesus (Rh) antigens on the rbc surface

cerebrospinal fluid (CSF)

- clear fluid that fills ventricles, subarachnoid space around brain and central canal of spinal cord - made by ependymal cells in choroid plexus - 80-150mL volume - similar composition to blood plasma - regular turnover: entire volume replaced about every 8 hours

external genitalia

- clitoris: produces pleasurable sensations during sexual activities, contains erectile tissue - labia: contain glands that lubricate the entrance to the vagina

fibres

- collagen (main structural protein, most abundant, amount and arrangement of fibres vary according to the tissue function, provides strength and cushioning, cartilage, bone, tendon, ligaments) - elastin (highly elastic protein, allows for coil and recoil, diminishes as we age, provides flexibility and elasticity, skin, arteries, bronchi) - reticular (structural proteins, form a delicate, irregular, flexible framework, inelastic, support cellular structures, spleen, liver)

corpus luteum (lutea, yellow)

- collapse of postovulatory follicle - remaining granulosa & theca cells proliferate > transformation to endocrine organ - secretes hormones: progesterone, oestrogen, relaxin and inhibin - stimulate maturation of uterine lining - if fertilisation occurs > becomes corpus luteum of pregnancy - if no fertilisation > spontaneous regression becomes corpus albican - corpus albicans = scar tissue-end of ovarian cycle

what is the nervous system?

- collection of nerve networks that send and receive information from the whole body - two main divisions of the nervous system: the central nervous system (CNS) > information processing (the brain, the spinal cord), the peripheral nervous system (PNS) > information IN and OUT of the CNS (nervous tissue outside of CNS)

ependymal cells

- columnal epithelial cell - cilia on apical end

folliculogenesis

- follicle development - follicles=oocytes+ supporting cells - primordial follicles: ~2 million primordial follicles stored in ovarian cortex, inactive/resting follicles, single layer of flattened follicular cells surrounding a primary oocyte arrested at end of prophase in meiosis - primary follicles: follicular cells enlarge> form several layers, follicular cells> granulosa cells when more than one layer is present, thecal cells= cells in the ovarian stroma (connective tissue), thecal & granulosa cells > work together > produce oestrogen and progesterone - secondary follicles: follicle wall thickens, follicular cells secrete fluid, zona pellucida (clear layer) forms around oocyte > protective layer - tertiary follicles: one secondary becomes a tertiary or mature follicle (graafian follicle), occurs about day 10-14 of cycle, has anthrum (fluid-filled chamber), granulosa cells form corona radiata (protective layer over the oocyte), at ovulation, tertiary follicle releases secondary oocyte into uterine tube, indicates follicular phase end and start of luteal phase

ovarian cycle

- follicular phase: 10-14 days, follicles produce mostly oestrogen, dominant follicles survives ~ by day 14, largest follicle bulges at ovary surface, increasing oestrogen levels trigger the secretion of LH by pituitary gland - luteal phase: 12-15 days, corpus luteum dominantly produces progesterone, if fertilisation does not occur, corpus luteum becomes corpus albicans, if fertilisation does occur, developing embryo secretes human chorionic gonadotropin (hCG) which maintains health of corpus luteum & its hormone secretions

transport of oxygen

- for transport oxygen is bound to haemoglobin found within red blood cells in the blood - each haemoglobin molecule contains four haeme groups with iron cores > oxyhemoglobin - one oxygen binds per haeme group - when oxygen binds to haemoglobin it causes a change to the shape of the proteins so that it appears bright red - when no oxygen is bound it appears blue-ish

axial skeleton

- forms central axis - skull, vertebral column, ribs, sternum, sacrum - 80 bones

Schwann cell function

- forms myelin in the PNS - release factors that can promote regeneration of an axon if damaged (assist in peripheral nerve regeneration) - one Schwann cell can myelinate one axon segment

oligodendrocyte function

- forms myelin the CNS - release factors that inhibit regeneration of axons if damaged - one oligodendrocyte can myelinate up to 15 axon segments

myocardium (muscular wall of the heart)

- forms the atria and ventricles of the heart - under involuntary control - coordinated contraction propels blood from the atria and ventricles - heart muscle works as single functional unit = force of contraction transmitted from cell to cell

melanocyte-stimulating hormone (MSH)

- from pars intermedia of anterior lobe - stimulates melanocytes of skin to increase melanin production - in adults, almost none produced

macula densa

- function: detects changes in blood Sodium (Na2+) concentration in DCT - increased GFR causes an increase in sodium concentration in DCT - increased adenosine is secreted by the cells > vasoconstriction of the afferent arteriole > decreased GFR - inhibition of nitric oxide synthase (an enzyme) > decreased nitric oxide > vasoconstriction of afferent arteriole > decreased GFR (known as tubuloglomerular feedback mechanism)

testes

- function: exocrine (produce sperm), endocrine (produce testosterone) - efferent ductules: connect rete testis to epididymis - tunica albuginea: outer capsule continuous with septa subdividing testes int lobules - seminiferous tubules: coiled tubules within lobules (total length ~1/2 mile/testis), site of sperm production - rete testis: tubules network outside of lobules

golgi complex

- function: modifies, sorts, packages and transports proteins received from the rough ER; forms vesicles that discharge processed proteins via exocytosis into extracellular fluid; forms membrane vesicles that ferry new molecules to the plasma membrane; forms transport vesicles that carry molecules to other organelles, such as lysosomes

blood glucose

- function: primary metabolic substrate for body, glucose (and fatty acids) is energy source for most cells, brain can only use glucose, brain and liver do not need insulin to facilitate uptake - regulation/metabolism: insulin and glucagon (pancreas), growth hormone (pituitary gland), adrenaline/epinephrine (adrenal gland), cortisol (adrenal gland) - storage: liver stores glucose as glycogen, releases it as glucose between meals

prostate gland

- function: secrete milky fluid containing citric acid for ATP production, enzymes for liquefaction of coagulated semen, 25% of semen volume, postate specific antigen (PSA)

loop of henle

- function: water conversation - a descending limb - an ascending limb

cartilage (chondro) - supportive, rubbery CT

- functions: resists compression/absorbs shock, smooth surface to minimise friction - cells (chondroblasts: secret cartilage matrix, located near edge, chondrocytes: chondroblasts trapped by matrix secreted, trapped in matrix within lacunae) - matrix: chondroitin sulphate (retains water = thus rubbery) - avascular, thus diffusion of nutrients & wastes to and from an external source - 3 types of cartilage: dependent on which type of CT fibre predominates - hyaline (articular) cartilage: equal amounts of collagen & elastin - fibrocartilage: collagen predominates - elastic cartilage: elastic fibres predominate

large intestine function

- further breaks down food residues - absorbs water, electrolytes & vitamins - propels faeces towards rectum

synapse neuron

- gap between neuron 1 and 2 - site of neurotransmitter release

nodes of Ranvier

- gaps in myelin - electrical signals 'jump' between these

mitochondria

- generate ATP through reactions of aerobic cellular respiration - play an important early role in apoptosis

insulin inhibit

- gluconeogenesis (creation of glucose from substrates such as amino acids) - glycogenolysis (glycogen breakdown and glucose release by liver) - lipolysis (fat break down) - ketogenesis - proteolysis (protein break down)

process of neurotransmission

1. action potential arrives at axon terminal 2. voltage-gated Ca2+ channels open 3. Ca2+ enters the presynaptic neuron 4 Ca2+ signals to neurotransmitter vesicles 5. vesicles move to the membrane and dock 6. neurotransmitters released via exocytosis 7. neurotransmitters bind to receptors 8. signal initiated in postsynaptic cell

fates of neurotransmitters

1. bind to postsynaptic receptors 2. destroyed by enzymes 3. re-uptake by presynaptic cell (recycled) 4. diffuse away 5. pumped back into glia (astrocytes)

anatomy of the uterus (macroscopic)

1. body upper portion 2. fundus 'dome' above level of entry of oviducts 3. cervix barrel-shaped inferior region, cervical cana - function: site of implantation & maintenance of embryonic & foetal development during pregnancy

functions of cerebrospinal fluid (CSF)

1. cushion 2. supply nutrients 3. waste control/removal

connective tissue

1. dense 2. loose - function: mechanical support and protection (the skeleton = cartilage and bone, dermis = support, fat = insulation, cushioning, protection), storage ( energy, adipose), defence (immunity, inflammation), repair (scarring, regeneration), communication and transport

endochondral ossification

1. development of a hyaline cartilage model of bone by mesenchymal cells 2. growth of cartilage model (length: chondrocyte division within matrix, width: formation of new cartilage at edge by chondroblasts) 3. cells in mid-region burst (changing pH of matrix, calcification & chondrocyte death) 4. primary ossification centre (artery penetrates into centre. brings in osteoblasts & osteoclasts, osteoblasts form new bone; osteoclasts form medullary cavity) 5. development of secondary ossification centre (blood vessels enter epiphyses at birth & spongy bone is formed) 6. hyaline cartilage remains: over epiphyses (articular cartilage), at epiphyseal plate for bone growth

nephrons structure (three basic functions)

1. glomerular filtration: in the glomerulus, blood plasma and dissolved substances (smaller than most proteins) get filtered into the glomerular capsule 2. tubular reabsorption: all along the renal tubule and collecting duct, water, ions, and other substances get reabsorbed from the renal tubule lumen into the peritubular capillaries and ultimately into the blood 3. tubular secretion: all along the renal tubule and collecting duct, substances such as wastes, drugs and excess ions get secreted from the peritubular capillaries into the renal tubule (these substances ultimately make their way into the urine)

erythropoiesis (erythrocyte production)

1. kidneys produces EPO 2. stimulates the bone marrow to produce rbc's 3. rbc's produced in the bone marrow, continual production 4. rbc's circulate in bloodstream, lifespan ~ 120 days 5. aged & defective cells recycled (by macrophages) in liver, spleen and bone marrow 6. heme from rbc's broken down and secreted in bile

how does a steroid hormone activate its target cell?

1. lipid soluble hormone diffuses into the cell 2. activated receptor-hormone complex and alters gene expression 3. newly formed mRNA directs synthesis of specific proteins on ribosomes 4. new proteins alter cells activity

blood glucose level cycle

1. low blood glucose (hypoglycaemia) stimulates alpha cells to secrete 2. glucagon acts on liver cells to: break down glycogen into glucose, form glucose from lactic acid and certain amino acids 3. glucose released by liver cells raises blood glucose level to normal 4. if blood glucose continues to rise, hyperglycaemia inhibits release of glucagon -- 5. high blood glucose (hyperglycaemia) stimulates beta cells to secrete 6. insulin acts on various body cells to: accelerate facilitated diffusion of glucose into cells, speed synthesis of glycogen from glucose, increase uptake of amino acids and increase protein synthesis, speed synthesis of fatty acids 7. blood glucose level falls 8. if blood glucose continues to fall, hypoglycaemia inhibits release of insulin