anatomy final (respiratory, urinary, digestive, reproductive)

respiratory function: gas exchange

primary function, provides O2 to blodd and removes CO2

respiratory function: acid base balance

regulates blood hydrogen ion concentration, pH, by controlling CO2 levels

respiratory function: speech (phonation)

air passing over vocal folds in the larynx creates speech sounds

respiratory function: defense against microbes

nasal cavity mucosa traps inhaled particles, macrophages in alveoli

respiratory function: regulation of chemical messengers

Lungs modify blood by removing some signals and adding/activating others, changing arterial blood composition, example ACE

respiratory function: blood clot dissolution

traps and dissolves blood clots from systemic circulation, often using tissue plasminogen activator

blood pH range

7.35-7.45, slightly alkaline

acidosis

pH less than 7.35, condition characterized by excess acid in blood, caused by CO2 retention, kidney disease, diabetic ketoacidosis

alkalosis

pH greater than 7.45, excessively high blood pH, caused by excessive CO2 removal, hyperventilation, vomiting, diarrhea

diabetic ketoacidosis (DKA)

body lacks insulin, cant use glucose, breaks down fat producing acidic chemical ketones, turn the blood acidic, body attempts to compensate for acidosis by performing kussmaul respirations to blow off CO2

primary signal for respiratory control

blood pH, as well as partial pressures of O2 and CO2

boyles law

at a constant temperature, the pressure of a gas is inversely proportional to its volume

air movement mechanism

lungs change volume in response to thoracic cavity changes, altering internal pressure, which drives air movement

changes for air movement into lungs

expanded thoracic cavity, increasing lung volume and decreasing intrapulmonary pressure below atmospheric pressure

changes for air movement out of lungs

diaphragm and rib muscles relax, shrink chest cavity, reducing thoracic volume and increasing internal air pressure above atmospheric pressure, passive in quiet breathing

pleura

a thin, two layered serous membrane that envelops the lungs and lines the chest cavity, separated by a small, fluid filled space

visceral pleura

directly covers the surface of the lungs

parietal pleura

lines the thoracic cavity

pleura cavity

space between visceral and parietal pleura

pleural fluid

fills the pleural cavity, sticks the lungs to the thoracic wall due to cohesive and adhesive properties like hydrogen bonds

intrapleural pressure

pressure within pleural cavity, normally negative, holds lungs open and prevent collapse, aided by opposing forces of chest wall expansion and lung elastic recoil, rises and falls but does not equalize with atmospheric

penumothorax

a condition where air enters the pleural cavity, leading to loss of negative intrapleural pressure and collapsed lung

primary inspiration muscles

diaphragm, external intercostals

diaphragm

dome shaped skeletal muscle, contracts and flattens to increase vertical thoracic volume

external intercostals

muscles between ribs, contract to spread ribs apart and push sternum forward, increasing anterior, posterior, and lateral thoracic volume

accessory muscles for inspiration

internal intercostals, pectoralis mino, sternocleidomastoid, scalene, serratus anterior, erector spinae

accessory muscles for forced expiration

internal intercostals, abdominal such as rectus, external oblique, internal oblique, and trasnverse abdominis, quadratus lumborum

internal intercostal muscle function

assist in elevating sternum and thoracic cage during inspiration, depress thoracic cage in expiration

pectoralis minor muscles function

elevate superior 5 ribs

sternocleidomastoid function

elevate sternum

scalene muscles function

elevate first and second ribs

serratus anterior muscle function

elevate and spread ribs, increasing diameter of thoracic cage

erector spinae muscles function

extend vertebral column to allow greater expansion of thoracic cage

abdominal muscles function

depress thoracic cage, compress abdominal contents, increase intra abdominal pressure and push diaphragm superiorly

quadratus lumborum muscles function

fixate 12th rib

normal, quiet expiration

passive, no muscle contraction, driven by elastic recoil of the lungs and thoracic cage

hiccup

spasm of diaphragm, causing air intake and epiglottis to slap shut over the glottis

sigh definition

slow, deep inspiration that is held and followed by a slow expiration

sigh function

reopens local groups of collapsed alveoli and stimulates release of surfactant

yawn definition

large sigh that takes the lung to maximum amount of air that can be forcibly inhaled

yawn function

opens collapsed alveoli, minimizes alveolar collapse during sleep and opens then after

sneeze definition

deep inspiration followed by a large, forceful expiration through the nose at the velocity of 100 mph

sneeze function

clears foreign or irritating substances from the nasal cavity

cough definition

small initial inspiration followed by forceful expiration primarily through mouth, 50 mph

cough function

clears the larynx, trachea, or lower airways

what regulates the nonrespiratory movements like sneeze and yawn?

mediated by the brainstem, medulla, involving cranial nerves IX and X

atmospheric pressure

the force exerted by surrounding air

intrapulmonary pressure

air pressure within the alveoli, rises and falls with inspiration and expiration, eventually equalizes with atmospheric

tital volume (TV)

volume of air inspired and expired during normal, quiet breathing, around 500mL

inspiratory reserve volume (IRV)

maximum volume of air that can be forcibly inspired after tidal inspiration, 1900 f and 3100 m

expiratory reserve volume (ERV)

maximum volume of air that can be forcibly expired after tidal expiration, 700 f and 1200 m

residual volume (RV)

volume of air that remains in the lungs after a forced expiration, 1100 f and 1200 m

inspiratory capacity (IC)

total amount of air that can be inspired after a tidal expiration, 2400 f and 3600 m, TV+IRV

functional residual capacity (FRC)

total amount of air that normally remains in lungs after a tidal expiration, 1800 f and 2400 m, ERV+RV

vital capacity (VC)

total amount of exchangeable air, max volume that can be inspired after max expiration, 3100 f and 4800 m, TV+IRV+ERV

total lung capacity (TLC)

total amount of exchangeable and nonexchangeable air, equal to sum of all pulmonary volumes, TV+IRV+ERV+RV, 4200 f and 6000 m

between breaths

no air movement, atmospheric and intrapulmonary pressure equal at 760 mm Hg, intrapleural at 756

inspiration

lung volume increases via thoracic expansion, intrapulmonary pressure, 758, decreases below atmospheric pressure, 760, air flows into lungs, intrapleural drops to 754

between inspiration and expiration

intrapulmonary pressure equals atmospheric, 760, no air movement, intrapleural at 754

expiration

lung volume decreases via relaxation, intrapulmonary, 762, increases above atmospheric, 760, air flows out of lungs, intrapleural increases to 758

what are alveoli

air sacs at the ends of respiratory bronchioles and alveolar ducts

type 1 alveolar cells

simple squamous, form most of wall, thin for efficient gas exchange

type 2 alveolar cells

simple squamous, sporadically located, produce and secret surfactant

alveolar macrophages

phagocytic cells for debris and pathogen defense

respiratory membrane

the thin barrier between alveolar air and capillary blood, consisting of alveolar and capillary walls and their fused basal laminae, optimized for diffusion

surfactant composition

mixture of phospholipids and proteins

surfactant function

lowers the surface tension of the water layer lining alveoli, increases lung compliance and prevents alveolar collapse

law of laplace equation

P=2T/r

alveolar surface tension

the inward collapsing force generated by water molecules at the air liquid interface within lung alveoli, caused by two or more water molecules in close proximity forming weak hydrogen bond, causing them to cluster and pull inward

law of laplace

states that the tension in the walls of a hollow spherical object is directly proportional to its internal pressure and radius, and inversely proportional to wall thickness, used to explain how vessels resist pressure

what happens to alveoli without surfactant?

smaller alveoli would have high pressure than larger ones, causing them to collapse due to inward force of hydrogen bonds

what happens to alveoli with surfactant?

surfactant reduces surface tension by disrupting hydrogen bonds between water molecules, equalizing pressure and stabilizing smaller alveoli

what stimulates the release of surfactant?

mechanical stretching of the alveoli during deep breathing or hyperventilation such as sigh or yawn, produced by type 2 alveolar cells

pulmonary gas exchange

occurs via diffusion and driven by pressure gradients, air flows from high to low

pulmonary compliance

ability of the lungs and the chest wall to stretch

ventilation perfusion (VQ) coupling definition

the matching of airflow, ventilation, to blood flow, perfusion, in pulmonary capillaries to optimize gas exchange, in alveoli

hypoxemia

abnormally low oxygen levels in blood

hypoxia

critical condition where tissues are deprived of adequate oxygen, causes rapid breathing, tachycardia, confusion, and cyanosis

changes in ventilation affecting perfusion: low alveolar PO2

pulmonary arterioles constrict to divert blood away from poorly ventilated areas towards well ventilated areas

changes in ventilation affecting perfusion: high alveolar PO2

pulmonary arterioles dilate

changes in perfusion affecting ventilation: low pulmonary capillary PCO2

bronchioles constrict to retain CO2 and maintain blood pH

changes in perfusion affecting ventilation: high pulmonary capillary PCO2

bronchioles dilate to allow CO2 to diffuse out and be exhaled

oxygen transport: loading in pulmonary capillaries

oxygen from alveoli binds to hemoglobin in erythrocytes, forming oxyhemoglobin

oxygen transport: unloading in systemic capillaries

oxyhemoglobin releases oxygen to tissue cells, which diffuses due to partial pressure gradients

why is the urinary system important?

maintaining proper concentrations of water and solutes in the plasma

total body water in the average adult

42 liters, split between intracellular and extracellular

intracellular water concentration

26 liters, 60% of total

extracellular water concentration

16 liters, 40% of total, 13 liters in interstitial and 3 liters in plasma

what other areas is fluid located, and what are they classified as?

aqueous and vitreous humor, cerebrospinal fluid, classified as extracellular

fluid return

interstitial fluid returned by lymphatic system to intravascular fluid, maintains consistent percentages

sodium electrolyte values

145 mEq/l in extracellular, 10 mEq/l in intracellular

potassium electrolyte values

4 mEq/l in extracellular, 140 mEq/l in intracellular

how much water is made and lost in a day?

2.5 liters, input equals output

water input mechanisms from least to most

catabolism, food, liquid intake

water output mechanisms from least to most

feces, lungs, skin, urine

what is the difference between sensible and insensible water loss?

sensible is detectable, insensible is not

urinary system function: acid base balance

regulates blood pH by getting rid of hydrogen ions, works with respiratory

urinary function: erythropoietin release

kidneys release erythropoietin when oxygen is low, stimulating red blood cell formation

kidney location

abdominal cavity,

how protected is the kidney?

not heavily guarded dorsally, vulnerable to bruising, covered by tough renal capsule