Bio Excretion In Humans And Respiration Flashcards
Two types of chem reactions in living cells
Anabolic
Simple molecules to complex ones
Eg. Deamination and respiration (oxidaton of glucose)
Catabolic
Complex molecules to simple ones
Eg, photosyntesis, glycogen from glucose
What is metabolism
Refers to sum of anabolic and catabolic reactions that take place in the body of an organism
These produce waste products, harmful when accumulate -> need for removal
What is excretion
It is the process by which metabolic waste products and toxic substances are removed from the body of an organism.
Excretory organs lungs
Product: CO2
Mode of excretion: Gas in expired air
Excretory organs kidneys and skin
Products: excess mineral salts and nitrogenous waste products
- mainly urea (protein deamination)
- uric acid (nucleic acid breakdown)
- creatinine (muscle protein breakdown)
Mode of excretion:
Kidneys- constituent of urine
Skin- constituent of sweat (small amt for nitrogenous waste products)
Excretory organs kidney skin lungs
Product: Water Mode of excretion: Kidney- main constituent of urine Skin- main constituent of sweat Lungs- water vapour in expired air
Excretory organs Liver
Product: bile pigments (from haemoglobin breakdown)
Mode of excretion: constituent of faeces via intestines
Human urniary system parts 6
- kidneys
- ureters
- hilus:
- sphincter muscle
- urinary bladder
- urethra
Human urniary system parts: kidneys
Organs where urine is produced
Human urniary system parts: ureters
Connect the kidneys to the urinary bladder
Human urniary system parts: sphincter muscle
Located at bottom of urinary bladder
Controls urination
Human urniary system parts: hilus
Concave depression where (renal artery, renal vein and nerves)(blood vessels) are connected to the kidney
Human urniary system parts: urinary bladder
Elastic muscular bag that temporarily stores urine
Human urniary system parts: urethra
Duct that urine passes from urinary bladder out the body
Structure of a human kidney parts 6
- Fibrous capsule
- Cortex
- medulla
- renal pyramid
- kidney tubule
- renal pelvis
(Urether -> bladder -> urethra)
Visualse the human urinary system rn
Kidney( Hilus)Kidney
|| Urethers ||
Urinary bladder
[. ]
>.Structure of a human kidney parts: fibrous capsule
A layer over the kidney yea idk what it does
Structure of a human kidney parts: cortex
Outer dark region, covered and prot by fiborous capsule
(( here (medulla(
Structure of a human kidney parts: medulla
Inner pale red region
Contains the renal pyramids
((Cortex( here(
Structure of a human kidney parts: renal pyramid
Conical structure located in the medulla
Radial stripes on it indicate kidney tubules/nephrons
((cortex( medulla
^ in here
Structure of a human kidney parts: kidney tubule (nephron)
Site of urine formation
(Rich supply of blood vessels)
((Cortex( med(renal pyramid)ulla(
^ in here
Structure of a kidney tubule (nephron) 5
- bowsman’s capsule
- proximal convuluted tubule
- loop of Henlé
- distal convoluted tubule
- collecting duct (several nephrons)
Visualise Structure of a kidney tubule/ nephron
(_____) bowmans capsule
((. ((==||
)). )). || collecting duct
(( ||. _____________________
||pct || dct. Medulla
||. ||
——- loop of henlé
Blood circulation at kidney tubule/ nephron 6 steps
- Blood enters K via renal artery
- Renal artery into many arterioles
- Each arteriole into mass of blood caps: glomerulus
- Blood leaves glomerulus to blood caps surrounding Ktubule
- Blood caps into venules, into branch of renal vein
- Blood exits K via renal vein
Two main processes for urine formation and where
- ultrafiltration (renal corpuscle: bowmans capsule and glomerulus)
- selective reabsorption (at renal tubule)
Ultrafiltration is a PASSIVE process that requires: 2
- High (hydrostatic) blood pressure at glomerulus
2. Filter- basement membrane around glomerular blood capillaries
Ultrafiltration: high (hydrostatic) blood pressure
- created by afferent arteriole (blood to) being wider than efferent arteriole (blood away)
- this forces most blood plasma out glomerular blood caps into bowmans capsules
Ultrafiltration: the filter - basement membrane
- partially permeable basement membrane acts as a filter
- small molc like water glucose AA min salts and nutrogenous waste prod can pass -> filtrate in bowmans capsule
- large molc like proteins rbc wbc platelets are retained
What is selective reabsorption
It is the reabsorption of useful substances from the filtrate as the filtrate passes thru kidney tubule/ nephron
Selective reabsorption steps 4
- At pct most min salts, glucose, aa are reabsorbed thru walls to surrounding blood cap -> diffusion, active trans. Water -> osmosis
- Loop of henlé : water
- Dct : water and min salts
- Collecting duct : water
Remaining fluid passes out into renal pelvis to form urine
What does urine contain 3/5
Ecess water
Excess salts
Metabolic waste products eg. Urea, uric acid, creatinine
Factors affecting composition of urine
- protein rich diet More urea - excess aa deaminated in liver - more liquids/ water foods ^ water potential - larger vol - high intake of salty food ^ Excess salts - ppl with diabetes ^ large amts glucose
How does person with diabetes has high conc of glucose in urine
- unable to store excess glucose as glycogen
- high conc of glucose in blood
- glucose filtered out of glomerulus as filtrate during ultraflitration
- nephrons unable to reabsorb glucose fast enough (SA)
Osmoregulation
Control of water and solite conc in blood, maintain constant water potential
Changes detected by hypothalamus
ADH prod by hypothalamus in brain -> pituitary gland -> ^ permeability of collecting ducts to water
What is ADH
Anti - diuretic hormone
Osmoregulation basis (homeostasis)
Stimulus > receptor > corective mechanism > effects of corrective mechanism > effects of effects of corrective mechanism > condition increases > normal condition
How does water potential relate to blood pressure
Blood vol ^ (contr. By removing excess salts and water), blood pressure ^
HBP-> blood vessels burst, stroke
Why are kidneys important?
- excretory organs (metabolic waste products)
- osmoregulators (wayer and solute conc -> water potential)
Steps for a dislysis machine 4
- Blood drawn from vein and pumped thru tubing in DM
- Tubing bathrd in dialysis fluid
- Walls of tubing are partially permeable - small molc out, large molc remain
- Filtered blood returned to arm
Features of dialysis fluid 2
- same conc of substances as healthy blood : stuff doesnt diffuse out into tubing, if lack it goes in
- no metabolic waste products : conc gradient, waste prod diffuse out & be removed
Features of dialysis machine 2
- Tubing is narrow long and coiled : ^SA to VR
- direction of blood flow opposite to flow of dialysis fluid : maintains steep conc gradient
Mechanism of breathing 4
- Increase in thoraic cavity
- Drop in pressure in lungs
- Pressure inside lower than atmospheric pressure
- Pressure diff. FORCES air into lungs
Aerobic respiration
Glucose broken down in presence of oxygen to RELEASE energy
By products are co2 and water
Glucose + oxygen -> carbon dioxide + water + learge amount of energy
Anaerobic respiration
Breakdown of glucose w/o o2 bur releases less energy eg, yeast = glucose -> ethanol + co2 + small amt of energy
Repsiration: during excercise 8
- Aerobic resp happens first : energy for muscular contractions
- ^ rate of breathing, ^o2 intake rate , ^ heart rate = glucose to muscles faster
- aerobic respiration not enough, anaerobic respiration to release E
- lactic acid conc in muscles = muscular fatigue + pain
- insufficient o2 = oxygen debt in muscles = need rest to recover
- rest = ^ breathing rate = sufficient o2 to repay debt
- lactic acid to liver, oxidised to energy, lactic acid to glucose
- lactic acid used up = o2 debt repaid, gluocse to muscles
Respiration vs photosynthesis 6
Respiration | photosynthesis
- Energy released| E stored in carbs
- O2 used, co2 and h2o released | opp.
- At all times | only w sunlight & chlorophyll
- Catabolic: breakdown | anabolic: buildup
- loss of dry mass | gain in dry mass
- exothermic | endothermic
Flow of air 7
Nasal cavity > pharynx > larynx > trachea > bronchi > bronchioles > alveoli
Nasal cavity
Fringe of hair and the mucous lauer on walls : trap dust
Air passes thru: warmed and moistened, harmful chems detected by sensory cells in mucous membrane
Trachea
Supported by Cshaped rings of cartilage
Epithilium of trachea and bronchi - 2 types of cells
-> gland cells secrete mucus, trap dust
-> cillated cells = hair like structure (cillia) sweep trapped particles into pharynx
Bronchi and bronchioles
Trachea divides into 2 tubes called bronchi -> numerous bronchioles -> cluster of aveoli
Alveoli
Air sacs, site of gaseous exchange
O2 enter blood via diffusion
Conc gradient of o2 maintained as ^ conc of alveolar air than blood, less co2 in alveolar for it to leave
Adaptation of alveoli
Numerous alveoli to ^SAtoVR
Alveolar&capillary wall: 1 cell thick = ^ rate of diffusion (short dist)
Inner alveolar surface coated with thin film of moisture = o2 dissolves
How is o2 transported
Binding to haemoglobin into oxyhaemoglobin (reversible)
How is co2 transported 4
1 Co2 cells from respiring cells to rbc
2 Co2 and h2o in rbc -> carbonic acid (enzyme carbonic anhydrase)
3 Carbonic acid to hydrogen carbonate ions diffuse out rbc
4 Most co2 carried as hydrogencarbonate
All reversed in lungs
Co2 out capillaries into alveoli, expelled when breathe out
Inhalation
Diaphragem contracts + flattens
Relax
Internal intercostal
Contract
External intercostal
Vol of thoriac cavity up
Air pressure in lungs down
Pressure ^ than atmos pressure
Air to environment
(Exhalation: opposite-ish)
Exhalation
Diaphragm relax + arch up
External intercostal
Relax
Internal intercostal
Contract
Vol of thoriac cavity down
Air pressure in lungs up
Pressure less than atmos pressure
Environment forced to lungs
Inspired vs expired air
Inspired: ^o2, less co2, not saturated, varited temp
Expired: less o2, ^co2, saturated, body temp
Compontents of tobacco smoke 4
Nicotine
Carbon monoxide
Tar
Irritants
Tobacco smoke effects: nicotine
Addictive
Releases adrenaline = blood clot easily, ^ risk of blood clot = risk of coronary heart disease
Tobacco smoke effects: carbon monoxide
Combines forming carboxyhaemoglobin (very strong bonds) = less ability to carry oxygen, narrows lumen of arteries, ^ bp, ^ risk of coronary heart disease
Tobacco smoke effects: tar
Carcinogenic (causes cancer) and causes uncontrolled cell division
Paralyses cillia lining aire passages
^ risk of lung cancer, dust in mucus cannot be removed = ^risk of bronchitis and emphysema
Tobacco smoke effects: irritants
Paralyse cilia lining air passages, consists of hudrongen cyanide -> tar risks w/o cancer
Respiratory diseases 3
Chronic bronchitis
Emphysema
Lung cancer
Repiratory diseases chronic bronchitis
epethilium lining blocked, excessive mucus prod, paralysed cilia lining =/= remove dust. Breathing diffc. as blocked airways + cough = lung infection
Respiratory diseases Emphysema
Partition walls of alveoli break down the to violent cough from bronchitis = less SAtoVR + lungs lose elasticity = cannot expand fully
Breathing diffculties, wheezing, severe breathlessness
Respiratory diseases lung cancer
Uncontrolled cell division -> lumps of tissue
Smoking = risk of mouth throat pancreas kidney urinary bladder cancer
