phys lab

• what does blood transport?

  • o2, co2, nutrients, waste, cells, hormones
• blood is composed of

  • plasma: ions, water, protein, waste
  • erythrocytes: rbc
  • leukocytes: wbc - immune function
  • platelets: cell fragments - clotting

  average blood volume

  • men: 5.5 L
  • women: 5.0 L
• erythrocytes

  • rbc
  • contain hb: carry o2 and co2
  • plasma: 55 %
  • buffy coat
  • rbc: 45 %
• methemoglobin

  • iron is in the wrong form
  • hb can't bind to o2
• carboxyhemoglobin

  • hb binds to co, has a higher affinity for co than o2
  • displaces o2 on hb = death
• anemia

  • low rbc = low hematocrit %
  • low hb
  • both decrease o2 carrying capacity
• lung structure

  • elastic and want to collapse
  • expand and cx to bring in o2 and co2
  • negative pressure (vacuum)
  • hole in thoracic cavity = lungs will collapse (pneumothorax)
• type 1

  • single layer thick
  • gas exchange with capillary
• type 2

  • surfactant
  • lines alveoli interior and reduces surface tension
  • infants are prone to respiratory distress
  • too young to produce surfactant
  • alveoli collapse and need artificial respiration
• tidal breathing: intercostals help

  • inspiration
  • diaphragm expands (cx)
  • increase chest volume, decrease pressure
  • air in
  • expiration
  • diaphragm relaxes
  • decrease chest volume, increase pressure
  • air out
• body regulates co2 and acid levels, not h

  • co2 + h2o --> h + hco3
  • chemoreceptors
• pink: 3100

  yellow: 500

  blue and orange: 1200

  A) inspiration

  B) tidal

  C) expiration

  D) residual

  E) inspiration capacity

  F) vital capacity

  
• vital capacity: max volume of air expired after max inspiration

  • restrictive lung disease: restricted lung expansion, loss of elasticity
  • pulmonary fibrosis: scars lungs, low compliance, loss of elasticity
  • respiratory distress syndrome: no surfactant, alveoli surface tension is too high, poor stretch
  • emphysema: low compliance
• fev - forced expiration volume

  • volume expired in 1 sec x vital capacity x 100
  • normal: > 80 %
  • borderline: 60-80 %
  • disease: < 60 %
  • obstructive lung disease: inflammation, mucus blocks airway
  • asthma: bronchoconstriction, mucus
  • emphysema: bronchioles narrow or collapse
• hyperventilate

  • increase o2, decrease co2, decrease h
  • integrator slows respiration (rate and depth)
• rebreathing (bag) and dead air (tube)

  • increase co2 and increase h
  • increase respiration
• exerted

  • mechanoreceptors and cortex
  • no gas exchange in artery
  • feed forward: increases respiration
• kidney: filters blood to get rid of waste

  • maintains homeostasis and plasma

  steps:

  • filtration
  • reabsorption
  • secretion
• nephron

  • functional unit of kidney
  • diff area = diff amount of reabsorbption
  • anything not reabsorbed = urine
  • filtration + secretion - reabsorbption = excretion
  • reabsorption: na, h2o, glucose, urea
  • secretion: h, creatinine, k
  • plasma like fluid filters into bowman's capsule (no protein)
• proximal tubule

  • unregulated reabsorption
  • 70% = na, cl, k, h2o into blood
  • 100 % = glucose and amino acids
  • h2o = osmosis
• loop of henle

  • medullary osmotic gradient allows control of volume of urine in collecting duct
  • descending: permeable to h2o, makes filtration concentrated
  • ascending: not permeable to h2o, reabsorbs k, na, cl
• distal tubule and collecting duct

  • distal tubule: adjustable reabsorption of na - aldosterone
  • collecting duct: adjustable reabsorption of h20 - adh
  • based on need
  • regulated reabsorption
• adh - antidiuretic hormone

  • h2o reabsorption
  • due to increase plasma osmolarity or decrease blood volume
  • aquaporins are inserted into the apical membrane of the cd and h2o reabsorption
  • less urine and dehydration
  • increase adh, decrease volume and [ ] (increase specific gravity)
• urine volume and concentration

  • late distal tubule and collecting duct: impermeable to water
  • increase volume and decrease osmolarity
  • late distal tubule and collecting duct: permeable to water
  • decrease volume and increase osmolarity
• na and k regulation

  • aldosterone is secreted by adrenal gland: increase na reabsorbed and k secreted
  • na: blood
  • k: distal tubule and collecting duct
  • leads to h2o absorption and increase map
• specific gravity - sg

  • measures solute concentration in solution
  • density of urine compared to h2o
  • high: 1.05 to 1.06
  • normal: 1.02 to 1.03
  • low: 1.008 to 1.012
• diabetes inspidius

  • no adh or aquaporin in collecting duct
  • increase urine and decrease sg
• diabetes mellitus - insulin problems

  • glucose in urine
  • increase urine and increase sg
  • increase glucose in blood, kidney can't absorb glucose
  • leads to h2o reabsorption and increase map
  • glucose holds water
• dehydration

  • due to sweat, fever, vomiting
  • decrease urine, increase sg
• glomerulonephritis: damaged glomerus

  • protein leaks into the filtrate
  • protein in urine