The Respiratory System

Respiration

The exchange of gases that occurs during breathing in organisms.

External Respiration

The actual exchange of gases (O2 & CO2) between the organism and the environment.

Cellular Respiration

The process responsible for producing energy (ATP) using sugars.

Gas Exchange in Animals

Involves the release of carbon dioxide to prevent acidic pH in tissues.

Fick’s Law

States that gas diffusion across a membrane is proportional to surface area and partial pressure difference.

Ventilation

Movement of the respiratory medium over the respiratory surface.

Respiratory Pigments

Proteins like hemoglobin in vertebrates and hemocyanin in invertebrates that transport gases.

Countercurrent Flow

Efficient mechanism where water flows over gills and blood circulates in opposite directions.

Cutaneous Respiration

Integumentary respiration using the skin for gas exchange.

Tracheal System

System of tubes in insects for gas exchange directly with cells.

Gills

Primary respiratory mechanism in aquatic organisms for oxygen intake.

Lungs

Respiratory organs in terrestrial vertebrates like birds and mammals for gas exchange.

Ventilation of Lungs

Process of moving air in and out of the lungs for breathing.

Transportation of Gases

Movement of gases throughout the body, often facilitated by respiratory pigments like hemoglobin.

direct diffusion in cell surface/membrane

Single-celled organisms as well as lower forms of animals are able to obtain oxygen from the environment through ___________.

desiccation

Respiratory organs must be moist (like nasal cavities with mucus), large enough, and protected from ______ (with hair and cilia for filtration).

hemoglobin

• Blood cannot carry sufficient oxygen and carbon dioxide in dissolved form to meet the body’s requirements; _______ helps enhance its capacity.

controls oxygen and carbon dioxide levels for the entire body by regulating the rate and depth of breathing.

cerebrospinal fluid, sensors

The brain monitors the pH of the _______ through _____ (reflecting carbon dioxide concentration in the blood).

Secondary control

__________ is exerted by sensors in the aorta and carotid arteries that monitor blood levels of oxygen as well as carbon dioxide (via blood pH).

Tracheae

systems of tubes.

Tracheoles

fluid-filled small channels within the end of tracheae.

 Spiracles

valves that open and close -allowing entry of air and can aid in preventing the loss of fluids in the system.

External gills

usually found as extensions of the

body; obtain oxygen from the water through simple diffusion

Internal gills

are found inside the body of the

organisms. It has filamentous structures which areheavily supplied by blood vessels. It has countercurrent flow that greatly enhances the

oxygen intake of the organism.

buccal cavity, opercular cavity, gill curtains

The ____________ of fishes are separated to the

____________ by __________ (differentiates the

pressures between the two cavities).

buccal pump

in suction phase, water enters the

mouth of the fish, where it slightly increases the

pressure present in the buccal cavity. Due to the difference in pressures, the water will move from high concentration, to low concentration.

Opercular pump

The water will then flow through the gill curtain then enters the opercular cavity. Upon the entrance of water in the opercular cavity, the mouth closes while the operculum opens. The difference in pressure will then again allow the water to move freely across the operculum to exit the system.

dual pump system of fishes

This type of respiration results in a unidirectional flow.

hematocrits , myoglobin

Many diving animals have unusually high ____________ (ratio of the volume of packed red blood cells to the volume of whole blood) and also muscles with high amounts of _________ (an oxygenbinding protein found in muscle cells)

salamander, anurans

Amphibian lungs are varied depending on species. The _____________ species have a simple, smooth-walled lungs while the ________ have subdivided lungs.

TRUE

The respiratory system of a frog includes the nares, glottis, trachea, and lungs. TRUE OR FALSE

Bronchioles, bronchi, and trachea

tubes leading into and out of the lungs.

Alveoli

tiny air sacs for transfer of air.

Avian lungs

_________ are improved as compared to other terrestrial vertebrates by the addition of an extensive system of air sacs.

25, 75

During the intake of air, about % passes through lung parabronchi while _% bypasses the lungs and goes to the air sacs ,

Bidirectional respiration

air enters and exits in the same opening, preventing the mixing of incoming and outgoing air.

Visceral pleura

Thin but tough covering epithelium of mammalian lungs.

Parietal pleura

lines the indeed surface of the chest.

Pleural cavity

maintains a negative intrapleural pressure which allows the lungs to be expanded The two pleura are closely in contact and are lubricated by the surrounding tissue. Every time the lungs expand and contract, the two pleura slide over onE another.

Inspiration or intake of gases -

ribs will be pulled upward with the help of the intercostal muscles while the diaphragm contracts and flattens. The volume of the lungs will increase thereby decreasing the pressure in the lungs. Since the atmospheric pressure has a higher concentration, it will rush into the system in order to equalize the pressures.

Expiration or the release of gases

the ribs will return to their normal position. The diaphragm relaxes which in turn decreases the volume of the lungs and increases its pressure. The increase of pressure in the lungs eventually forces the air to exit the system.

FALSE, LOW, 5%

The heme group (low affinity)

constitutes to 50% of the molecule which contains

the iron group and the color red while the remaining 95% is the globin group which is a colorless protein.