• supply blood with O₂
• disposes of CO₂ (regulates pH: higher CO₂, lower pH)
• produces sounds

NASAL CAVITY

• conducting zone (passage of air)
• airway for respiration
• filters, humidifies and warms air (nasal conchae)
• resonates sound for speech
• houses olfactory receptors (cribiform plate)

PHARYNX

• connects nasal cavity and mouth
• Nasopharynx- behind nasal cavity, containg pharyngeal tonsils
• Oropharynx- behind mouth, contains palatine and lingual tonsils
• Laryngopharynx- continuous with esophagus and larynx, below epiglottis

LARYNX

• supports open airway, voice production, routes air and food into proper channels 
• Thyroid Cartilage- laryngeal prominence (adam's apple)
• Epiglottis- covers trachea during swallowing
• Cricoid and Arytnoid Cartilage- contain vocal ligaments
• Vocal Folds (true)- sound production, form glottis (opening)
• Vestibular Folds (false)- protects, support vocal folds

TRACHEA

• in mediastinum: post. to heart, ant. to esophagus
• Mucosal Layer to lumen (ciliated pseudo-strat columnar epith., moves mucous up

       Goblet Cells- produce mucous

         Cilia- beat only up to propel mucous to pharynx 

• Trachealis- smooth muscle on post. surface
• Tracheal Cartilage- hyaline, C-rings (non-collapsable)
• Carina- divides into primary bronchi

BRONCHI

• Primary (main)- Right is wider and shorter, Left is slimmer and longer
• Secondary (lobar)- one in each lobe of lung
• Tertiary (segmental)- less cartilage, more smooth muscle

BRONCHIOLES

• no cartilage, only smooth muscle
• control air flow and resistance
• Terminal- just before alveoli
• Respiratory- contain alveoli
• Bronchodilation- more airflow- fight or flight (sym. ANS)
• Bronchoconstriction- rest and digest (parasym. ANS/histamine)

LUNGS

• sacs of simple squamous epith
• Pneumocytes I- thin, flat, form sacs
• Pneumocytes II- septal cells (release surfactant to reduce surface tension), prevent sacs from collapsing
• Alveolar macrophages- phagocytize dust/pathogens

• where blood cap. and alveoli touch (gas exchange surface area)
• thin and moist membrant (b/c of surfactant)

EXTERNAL

1. Pneumocyte I
2. Basement Membrane
3. Endothelial Cell (of blood cap.)

INTERNAL (blood plasma)

• Breathing
• 3 Processes

1. Pulmonary Ventilation
2. External Respiration
3. Internal Respiration

• mechanics of moving air in and out

1. Inspiration
2. Expiration

• Volume of thoracic cavity increases, draws O₂ in
• Decrease in lung pressure (less than atmospheric)- 758 mmHg

1. Diaphragm flattens
2. External intercostals contract; raises ribs

• Deep- scalenes (neck), sternocleidomastoid, pectoralis minor, serratus anterior

• Volume of thoracic cavity decreases, CO₂ pushed out
• Increased lung pressure (763 mmHg)

1. Diaphragm moves sup.
2. Internal intercostals and transversus thoracis contract 

• Forced expiration- abdominal muscles contract

• Gas exchange in LUNGS 
• Partial Pressure Concentration Gradient: HI --> LO 
• O₂ --> blood cap. (internal)
• CO₂ --> alveolus (external)

• Gas exchange in TISSUES
• Partial Pressure Concentration Gradient:     HI --> LO
• O₂ blood --> tissues
• Cell CO₂ production --> blood cap.

External Resp.

HIGH 

P O₂ = 100 mmHg (Alveolus)

P CO₂ = 45 mmHg (Pulm. Art.)

LOW

P O₂ = 40 mmHg (Pulm. Cap.)

P CO₂ = 40 mmHg (Alveolus)

• exchange at Pulm. Art. of cap. - deoxy blood
• Pulm. Veins have same partial pressures as alveolus --> NO GAS EXCHANGE (already O₂ rich)

Internal Respiration

HIGH

P O₂ = 95 mmHg (Art.)

P CO₂ = 45 mmHg (Tissue-IF)

LOW

P O₂ = 40 mmHg (Tissue-IF)

P CO₂ = 40 mmHg (Blood Cap.) 

• exchange at Art. end of cap. - oxy blood
• Veins have same partial pressures as tissues --> NO GAS EXCHANGE (CO₂ rich)

• P O₂, P CO₂, H⁺
• Carotid Bodies- monitor how much O₂/CO₂ in blood going to brain

      -on coratid sinus (behind ear)

• Aortic Bodies- monitor how much O₂/CO₂ in blood going to visceral organs

      -on aortic arch

• Medulla Oblongata- houses respiratory centers 

• Vital Capacity (VC)- max air in & out of lungs

VC = TD + IRV + ERV 

• Tidal Volume (TD)- normal breathing
• Ispiratory Reserve Volume (IRV)- forced inspiration
• Expiratory Reserve Volume (ERV)- forced expiration
• Residual Volume (RV)- remaining in lungs after forced expiration
• Total Lung Capacity (TLC)- total volume 

TLC = VC + RV

O₂

• 98% bound to Hb (HbO₂)
• 2% dissolved in plasma (forms gas)

 CO₂

• 70% Carbonic Acid (H₂CO₃)
• 23% bound to Hb
• 7% dissolved in plasma (forms gas) 

O₂

                     Lungs

                       -->

DeoxyHb + 4 O₂        OxyHb

                        <--

                                                 Tissue

CO₂

CO₂ + H₂O <carbonic anhydrase> H₂CO₃ <-> H⁺ + HCO₃^-

• too much CO₂ in blood = low pH (acidic)
• blood pH = 7.4 

OXYGEN-HEMOGLOBIN DISSOCIATION CURVE

Hb affinity for O₂ varies

higher P O_2, higher affinity (more O_2, more sticky)

• Lungs- High (100%), high P O_{2 (100 mmHg)}
• Tissue at Rest- Low (75%), low P O_{2 (40 mmHg)}
• Tissue Excercise- Very Low (35%), very low P O_{2 (20 mmHg)}

Lower Hb affinity for O₂ (more O₂ to cells)

• High Temp
• Low pH (acidic)

Higher Hb affinity for O₂ (no O₂ for cells)

• Low Temp
• High pH (basic) 

excessive bronchoconstriction

limited airflow

*Albuterol- smooth muscle relaxer 

autosomal recessive

• Exocrine gland _{(too much mucous)}
• Integument _{(too much sweat)}
• Respiratory _{(hard to breathe, recurring infections)}
• Digestive _{(pancreas stop enzyme production, can't digest food)}

Destruction of alveoli (cells not enough O₂)

Pneumoctyes replaced by fibroblasts_(collagen) - NO DIFFUSION

*need O₂ tank- forces faster diffusion 

inflammation of the alveolar wall (respiratory membrane)

fluid leaks into alveolar sacs, comprised function

can be fungal, bacterial, or viral 

Ingestion

Digestion

Absorption

Elimination

breakdown of food molecules 

1. Mechanical- chewing (mouth), churning (stomach), segmantation (intestines)
2. Chemical- enzymes hydrolyze molecular bonds (intestines)

nutrients enter blood, lymph

• amino acids, glucose, glycerol (fatty acids)-building blocks

removal of wastes

POOP, URINE

Connective tissue

1. Parietal- lines interior abdominal wall
2. Peritoneal Cavity
3. Visceral (serosa)- directly covers organs

folds in membranes to secure organs

-where membranes fuse (sides, front/back)

1. Mucosa- Epith (st. sq., sim. col.), Lamina Propria (areolar ct), Muscularis mucosa
2. Submucosa- contains ct, vessels, nerves, glands
3. Muscularis Externa- circular inner, longitudinal outer (peristalsis, sphincter)
4. Serosa- tough ct, sim. sq. epith.

-enzyme released by salivary glands in oral cavity

-digests CARBS

-lubricates food- bolus

-rich in bicarbonate ion (HCO₃^-) to neutralize acidic food

-produced by chief cells in gastric glands into stomach

-inactive until reacts with HCl to make pepsin

-acive state digests PROTEINS

pepsinogen + HCl -> pepsin

(inactive)                 (active)

-produced by Chief Cells in gastric glands into stomach

-active enzyme

-digests PROTEINS

pepsinogen + HCl -> pepsin

(inactive)                 (active)

-produced by pancreas 

-enter duodenum

-digests CARBS/POLYSACCHARIDES 

-produced by pancreas (acini) and released in duodenum

-inactive, reacts with enterokinase -> trypsin

-helps to digest PROTEINS

Tysingogen + enterokinase -> trypsin

(inactive)                              (active)

-produced by pancreas and enters duodenum

-activated by enterokinase 

-digests PROTEINS

trypsinogen + enterokinase -> trypsin

(inactive)                              (active)

-produced by pancreas, released into duodenum

-digests LIPIDS 

-produced by simple columnar cells on microvilli in duodenum

-final breakdown of di- saccharides/peptides/fatty acids chains-> simple sugars/amino acids/fatty acids

-hormone produced by G cell of gastric glands in stomach

-stimulated by stretch receptors in stomach

-stimulates gastric glands to activate stomach 

GASTROINHIBITORY PEPTIDE 

(GIP)

-hormone secreted by enteroendocrine cells in intestinal crypts (tell enzymes what to do)

-antagonist of gastrin

-stimulated by glucose/chyme

-decrease stomach activity

-increase insulin production (pancrease)to absorb glucose

-hormone produced by enteroendocrine cells in intestinal crypts 

-stimulated by chyme

-increase HCO₃^- rich mucous release by pancreas 

-increase bile secretion by liver

CHOLECYSTOKININ

(CCK)

-hormone produced my enteroendocrine cells in intesinal crypts

-stimulated by lipid/chyme

-increase bile ejection from gallbladder

-increase secretion of pancreatic enzymes

-stimulates peristalsis and secretion in esophagus, stomach, pancreas, intestines 

-stimulates release of bile in liver

stimulated by vagus nerve/stretch receptors 

submucosal:

-senses the environment within the lumen

-regulates GI blood flow

-controls epithelial cell function (mucous, chief, parietal, g) 

myesteric:

-controls involuntary muscles along GI tract

-results from sight, smell, thought, or taste of food

-causes secretion of histamine and HCl in stomach 

-inhibits parietal and G cells

3-4 hours

-stimulated by stomach distension (stretch), food in stomach, lowered pH

-stimulates parietal and G cells

-protein breakdown

-food in duodenum triggers intestinal gastrin 

-inhibits vagus nerve: pyloric shincter tightens and prevents more food from entering

-gastric inhibition, pancreatic secretion, bile secretion

rhythmic contraction of circular muscles in small and large intestines

no directional mvmt

increase absorption

swallowing

closes epiglottis

from pharynx to esophagus

chewing

food is crushed and ground by teeth

cleavage of chemical bonds by addition of water

brush border enzymes:

polysaccharides -> monosaccharides

(sucrose + H₂O -> fructose + glucose)

polypeptides (proteins) + H₂O-> amino acids

FED

-digestion, absorption and transport of nutrients

-up to 4 hours after meal

-catabolic and anabolic are both active

-glycogenesis to form glycogen and release insulin to use up glucose from blood

HUNGER

-post-absorptive

4+ hours after meal 

-no dietary intake

-catabolic run by energy stores

-glycogenolysis  to break down glycogen and release glucagon 

-gluconeogenesis: make glucose from non-carb source (adipose)

-gastroesophageal

-between esophagus and stomach 

control exit of feces

internal- involuntary

external- voluntary 

Hepatopancreatic sphincter

controlling secretions from the liver, pancreas and gall bladder into the duodenum

-produced in liver

-stored in gallbladder

-function: emulsify fat 

-release stimulated by CCK 

       Pancreas/duodenum

                   |

       Common bile duct

           /               \

  cystic duct     common hepatic duct (R&L)

rxns in body cells used to generate and control Energy 

glucose supplies Energy to make ATP (for growth, repair, reproduction: all jobs)

build up of small nutrients to large organic molecules

Requires Energy

break down of large organic molecules to small nutrients 

Releases Energy

-last resort for Energy (4 Cal/g)

-amino acids used for structural, enzymes, hormones, antibodies, hemoglobin 

-found in meats, nuts, beans, dairy, eggs

-short term Energy supply (4 Cal/g)

-used in blood or stored for later

-found in grains (wheat, rice, oats, corn), fruits, veggies

1. Monosaccharides (1 C ring)

      glucose, fructose

2. Disaccharide (2 C rings)

      sucrose, maltose

3. Polysaccharide (many C rings)

     starch, glycogen, cellulose (fiber)

-long term Energy reserve (9 Cal/g)

-for padding, insulation (stored in hypodermis, around organs), carry fat in blood (lipoproteins: HDL, LDL)

-found in nuts, red meat, milk, eggs, butter 

Glycogenesis 

(absorptive;insulin release)

glucose -> glycogen (stored sugar) 

Glycogenolysis

(fasting;glucagon release)

glycogen -> glucose

Gluconeogenesis

(glucose from new energy source)

non-carb (adipose) -> glucose

Gastroesophageal Reflex Disease

heart burn

acid from stomach enters esophagus bc cardiac sphincter is relaxed

crystallization of bile components due to cholesterol (most common) or overproduction of bilirubin

most common in females 40+

-hormone released by islet (besta) cells in pancreas

- decrease blood glucose

- cells use glucose for Energy: GLYCOGENESIS, adipogenosis

-absorptive state (after meal)

-hormone released by islet (alpha) cells of pancreas

-increase blood glucose

-cells use fat for Energy: GLYCOGENOLYSIS

-fasting (between meals)

-hormone released by thyroid gland (follicular cells)

-increase cell basal metabolic rate (BMR)

-without this, cells can't use glucose to make ATP

-hormone produced by pituitary gland

-builds muscle, bones, connective tissue