Ball State University ANAT 201 Essien Exam 6

respiratory system

a system of organs, functioning in the process of gas exchange between the body and the environment, consisting especially of the nose, nasal passages, nasopharynx, larynx, trachea, bronchi, and lungs

functions of the respiratory system

gas exchange, regulation of blood pH, voice production, olfaction, protection, helps create pressure gradient for flow of lymph and venous blood, and holding breath while contracting abdominal muscles helps to expel abdominal contents during urination, defecation, and birth

organs of the respiratory system

nose, pharynx, larynx, trachea, bronchi, lungs

alveoli

air sacs in the lungs

divisions of the respiratory system

conducting division and respiratory division

conducting division

passages for airflow, nostrils to bronchioles

** w/o exchange of gases

respiratory division

consists of alveoli and other gas exchange regions

** w/ gas exchange

upper respiratory tract

nose, pharynx, larynx

lower respiratory tract

larynx, trachea, bronchi, lungs

pharynx

throat, the common passageway for food from the mouth and for air from the nose

• nasopharynx, oropharynx, laryngopharynx

nasopharynx

pseudo stratified epithelium

oropharynx

stratified squamous epithelium

laryngopharynx

stratified squamous epithelium

larynx

• voice box; passageway for air moving from pharynx to trachea; contains vocal cords

• keeps food out of the airway with epiglottis

lower respiratory tract extends from the _______ to the ________

trachea, pulmonary alveoli

trachea

windpipe

trachea wall

basal stem cells

• mucocilary escalator -----> mechanism for removing inhaled debris

bronchi

trachea branches into the right and left primary bronchus

right primary bronchus

• supplies the right lung

• larger and and at a steeper angle

• creates a more likely pathway for foreign objects

left primary bronchus

supplies left lung

bronchial tree

branched airways that lead from the trachea to the microscopic air sacs called alveoli

bronchial tree consists of ________, __________, and _________

main (primary) bronchi, secondary (lobar) bronchi, and segmental (tertiary) bronchi

bronchioles

smallest branches of the bronchi

terminal bronchioles

final branches of conducting zone

respiratory bronchioles

beginning of the respiratory division

each respiratory bronchiole divides into __________

alveolar ducts that end in alveolar sacs, clusters of alveoli

in the state of relaxation, the parasympathetic division keeps the bronchioles ____________

partly constricted

during exercise, the sympathetic nerves _____________

dilate the bronchioles to increase air flow

nasal cavity

all bronchi are lined by

ciliated pseudostratified columnar epithelium

three types of cells found in alveoli

• squamous (type I) alveolar cells

• great (type II) alveolar cells

• alveolar macrophages (dust cells)

squamous (type I) alveolar cells

• 95% of surface area

• respiratory membrane is a site of gas exchange... consists of type I cell and capillary cell

great (type II) alveolar cells

• 5% of surface area

• provide surfactant: a phospholipid material that coats the alveoli and prevents them from collapsing during exhalation

alveolar macrophages (dust cells)

phagocytose small particles in alveoli

the pleurae

visceral pleura, parietal pleura, pleura cavity

visceral pleura

covers the lungs

parietal pleura

lines the thoracic cavity

pleural cavity

lungs

functions of the pleurae

reduce friction, create pressure gradient, compartmentalization

compartmentalization

• most important function of the pleurae

• prevents spread of infection

the respiratory muscles

diaphragm, internal & external intercostal muscles, other muscles of chest, neck, and abdomen

the pectorals minor, sternocleidomastoid, and erector spinae are active during ____________

deep inspiration

when exhaling forcefully/rapidly the ____________ and ___________ help to expel air from the lungs

internal intercostals and abdominal muscles

respiratory neuroanatomy

the rhythm of unconscious breathing is set by nuclei in the medulla and pons

what 2 respiratory nuclei are in the medulla?

ventral respiratory group and dorsal respiratory group

ventral respiratory group

primary generator of the respiratory rhythm

dorsal respiratory group

• receives input from the pontine respiratory group, chemoreceptors, and stretch receptors in the lungs

• modifies output from the ventral respiratory group to adjust breathing rhythm

higher brain centers

cerebral cortex, limbic system, hypothalamus

the aging respiratory system

• ventilation declines after the 20s

• loss of elasticity in lungs, thoracic cage

• fewer alveoli in old age

• elderly less capable of clearing pathogens

emphysmea

breakdown of alveolar walls

digestive system

body system the breaks down food and absorbs nutrients

functions of the digestive system

ingestion, digestion, absorption, compaction, defecation

ingestion

taking in food

digestion

mechanical and chemical breakdown of food into nutrient molecules

absorption

movement of nutrients into the bloodstream

compaction

absorption of water and consolidation of indigestible residue

defecation

elimination of feces

2 main groups of the digestive system

alimentary canal and accessory digestive organs

alimentary canal

(gastrointestinal/ GI tract) digestive tube that extends from the mouth to the anus

alimentary canal organs

mouth, pharynx, esophagus, stomach, small intestine, large intestine, anus

accessory digestive organs

teeth, tongue, salivary glands, liver, gallbladder, pancreas

layers of digestive tract

mucosa, submucosa, muscularis externa, serosa

teeth

mechanically break down food

how many decidous teeth (baby teeth) begin to emerge at ages 6 months to 30 months?

20

when are the deciduous teeth replaced by permanent teeth?

6 years- 25 years old

When do third molars (wisdom teeth) erupt?

between 17- 25

salivary glands

glands of the mouth that produce saliva, a digestive secretion

saliva contains

mostly water, amylase, lipase, mucus, lysozyme, electrolytes, immunoglobulin A

amylase

enzyme in saliva that breaks the chemical bonds in starches

lipase

enzyme that breaks down fat

mucus

lubricates food

lysozyme

enzyme that kills bacteria

where does digestion start?

mouth

what controls salvation?

nuclei in the medulla oblongata and pons

salvation is mostly under ____________ control

parasympathetic

the pharynx and esophagus are lined with _________

nonkeratinized stratified squamous epithelium

stomach

large muscular sac that continues the mechanical and chemical digestion of food

chyme

partially digested, semiliquid food mixed with digestive enzymes and acids in the stomach

chyme passes from the stomach to the __________

small intestine

when muscles contract, the sphincter will (open/close) to let chyme from the stomach into the small intestine (duodenum)

open

when relaxed the sphincter is (open/closed)

closed

cardiac region of stomach

near the heart

fundic region of stomach

dome-shaped portion superior to esophageal attachment

pyloric region of stomach

the passageway to the duodenum