biology-respiratory system

what is respiration

process in which body allows for oxygen delivery in cells to break down glucose and CO2 removal from cells out of body that is exhaled out of the lungs and is all done by respiratory system

requirements for respiration to occur

1 surface area or respiratory surface (for large amounts of gas exchange at fast enough rates to meet bodies needs )

2 moist environment (so O2 and CO2 can be dissolved in water)

what are the stages of respiration

breathing, external respiration, internal respiration, cellular respiration

first stage of respiration and funtion

breathing-inspiration (breathing) aka moving air from external environment into lungs and expiration (exhaling) aka moving air from lungs back into external enviroment

second stage of respiration and function

external respiration- exchange of oxygen and carbon dioxide between air and blood

third stage of respiration and function

internal respiration- exchange of oxygen and carbon dioxide between body tissues and cells

fourth stage of respiration and function

cellular respiration- series of energy releasing chemical reactions that break down glucose to produce ATP or energy that can be used around body.

what is the main principle organ in respiration

the lungs, located deep in the body

what are lungs protected by

thoracic cavity

what is the thoracic cavity

a bone and muscular structure used to protect the lungs

where does thoracic originate from

greek word meaning chest place

what is the respiratory tract

passageway that air moves from external environment to respiratory surface

what does upper respiratory tract include

nose, mouth, nasal passages, pharynx, epiglottis, larynx and trachea

what is the nasal passage

first organ of respiration, main function is to warm, moisten and clean incoming air. lined with mucus producing cells that trap foreign particles and ciliated particles which move these particles. (these particles can include bacteria and dust)

what are the turbinate bones

very thin bones, that project into nasal cavity and increase surface area of cilia, for warming air and removing particles

what is the pharynx

second organ of respiration. known as throat, passageway for air getting into respiratory system as well as passageway for food and water to get into digestive system

what is the epiglottis

third organ of respiration, flap of cartilage that lies behind tongue and above the larynx that closes over opening of trachea (glottis).

what is epiglottis function

When a person swallows epiglottis prevents food and water from entering trachea and passing into lungs. When a person is at rest epiglottis is up right, allowing air to pass to lower respiratory tract

What is the larynx

“voice box'“ made from cartilage and contained vocal chords

how do vocal chords work

when you breath, there is a large gap between them but when you speak, muscles around them contract causing them to come closer together and vibrate- producing sound or pitch

what is pitch

determined on length of vocal cords which determine a higher or lower pitch. (longer the chords the lower or deeper the pitch.

what is the trachea

“windpipe” that extends from larynx to the bronchi that is strengthened by cartilage arches that prevent it from collapsing.- open section of semicircle cartilage fases the esophagus to allow it to expand for the swallowing of food

structures of the lower respiratory tract

lungs, bronchi, bronchioles, alveoli and capillaries

primary organ of respiration and what does it contain

lungs-contain the bronchi, bronchioles and alveoli.

how are lungs divided

divided into regions called lobes.

number of lobes per lung

right contains 3 lobes and left contains 2 lobes to have space for the heart.

what is the pleural membrane

thin, double layered membrane that surrounds each lung (outer membrane attaches to chest wall and inner membrane attached to outside of lung

what does pleural membrane do

they adhere to each other allowing lungs to expand and draw in air when volume of chest cavity is increased as well space between membranes contains fluid to reduce friction during inhalation

what are the bronchi

the branching of the trachea (2 bronchi) that enter left and right lung

what are bronchi made of

contain c shaped cartilage rings that provide support as part of the bronchus wall

what does bronchi branch into

smaller network of fine tubes called bronchioles within each lung

what are bronchi and bronchioles lined with

cilia and mucous producing cells

what do cilia do in the bronchi and bronchioles

movies foreign particles upward to upper resp. tract to be ejected by coughing, sneezing or swallowing

what does mucous do in the bronchi and bronchioles

captures and traps particles and pathogens

structure of alveoli

cluster of tiny sacs and the end of each bronchiole which forms spongy lung tissue. composed of single layer of cells for rapid gas exchange occurring in external respiration. surrounded by network of capillaries.

function of alveoli

functional part units of lungs. During inhalation alveoli are bubble shaped but during expiration tiny sacs collapse.

what causes alveoli to not stick together

film of fat called lipoprotein preventing membranes from sticking

what are capillaries

tiny blood vessels that surround the alveoli, only one cell thick and connect arteries and veins

concentration of oxygen in capillaries and alveoli

air that enters alveoli have a higher concentration of oxygen then blood in capillaries. oxygen diffuses out of alveoli and into blood of capillaries

what transfers the oxygen

diffusion transports most of oxygen but about 30% of oxygen is transported by facilitated diffusion where protein molecules “carry” oxygen across cell membrane. not requiring more energy but speeding up process

where does external respiration take place

in the lungs

process of external respiration

1. oxygen diffuses into the blood of capillaries to begin journey to heart and to be pumped into tissues

2. carbon dioxide diffuses from blood in capillaries to alveoli in lungs to be released into external environment

where does internal respiration take place

takes place in body tissues

process of internal respiration

1. oxygen diffuses from the blood into oxygen-poor tissues

2. carbon dioxide diffuses from tissue to blood -to heart

first step of oxygen transport

oxygen moves from atmosphere (high partial pressure) to alveoli then diffuses into blood and dissolves in the plasma

what increases solubility of oxygen into the blood

hemoglobin

what is hemoglobin

respiratory pigment of red blood cells the increase the oxygen carrying capacity of blood (20mL—100mL)

what does hemoglobin consist of

4 polypeptides composed of heme (iron containing pigment) and globin(protein component)

bond between oxygen and hemoglobin

when oxygen dissolves into plasma, hemoglobin forms weak bond with oxygen to form oxyhemoglobin

what does the amount of oxygen binding depend on

partial pressure . -in lungs around 13.3 KPa, thus blood leaving lungs is nearly saturated in oxygen

what happens to partial pressure as it enters capillaries

as it enters capillaries in tissues, partial pressure drops to about 5.3 KPa, (drop in pressure causes dissociation or split of oxygen from hemoglobin and oxygen diffuses into tissues.)

solubility of carbon dioxide

20 times more soluble than oxygen (approximately 23% of CO2 is carried in blood by hemoglobin, 7% is carried by plasma, 70% is dissolved and carried in in blood as bicarbonate ions (H2CO3))

reaction of CO2 and H2O in blood

carbon dioxide and water combine to form bicarbonate ions with enzyme carbonic anhydrase

concentration of carbon dioxide in blood from tissues

the concentration decreases (CO2) in plasma, maintaining low partial pressure so that CO2 continues to diffuse into blood from tissues

what do acids in the blood do

can create problem and change pH of blood resulting in death and must be buffered

what happens to unstable carbonic acid

it dissociates to bicarbonate ions and hydrogen ions, then hemoglobin binds with hydrogen to act as a buffer

what happens to hemoglobin and hydrogen

once the venous (deoxygenated) blood reaches lungs oxygen dislodges H+ and hemoglobin and free H+ and bicarbonate ions combine to form CO2 and water again. Carbon dioxide diffuses from blood into alveoli to be exhaled

what controls air pressure in lungs

the diaphragm and rib muscles contracting and relaxing

what is the diaphragm

dome shaped layer of muscle that separates thoracic cavity (region of lungs) from abdominal cavity (region of stomach and liver)

what are rib muscles

INTERCOSTAL MUSCLES- found between ribs and along ventral or inside surface of ribs

what is inspiration

(inhalation)

process of inhalation

begins with nerve stimulus that causes external intercostal muscles of ribs to contract, lifting rib cage up and out and at the same time diaphragm contracts to pull downward.

what do the intercostal muscles contracting and the diaphragm contracts to pull downwards heffect

this causes an increase in volume of thoracic cavity and increase of gas molecules spread apart (less outward pressure) This change in pressure causes the walls of the lungs to expand outward into the thoracic cavity and air to rush into the lungs form the external.

what is expiration

exhalation

actions of diaphragm and intercostal muscles

diaphragm and external intercostal muscles relax and internal intercostal muscles contract - reducing volume of thoracic cavity

what does the change in pressure during exhalation cause

pressure will increase in lungs and air will be forced out of lungs to the low pressure of the environment

what is pneumothorax

when air accumulates inside chest space between plural membranes that line the lungs and inner chest wall

effects of pneumothorax

pressure of air causes lung to collapse, normally caused by puncturing injury or lung damage (treatment is inserting a needle or chest tube between ribs to get rid of excess air)

what are breathing movements controlled by

chemoreceptors (nerve receptors, in medulla oblongata and detects levels if CO2)

tidal volume

volume of air inhaled and exhaled on a normal breath

inspiratory reserve volume

additional amount of air that can be taken into lungs beyond regular tidal inhalation

expiratory reserve volume

additional amount of air tha can be expelled