Respiratory System

Respiration

• is the process of inhaling and exhaling air, including oxygen and carbon dioxide.

• Oxygen is the most critical requirement of life support for an animal, which can only survive a few minutes without it.

Trachea

When a person inhales, air travels down the ____ through the bronchial tubes and into the lungs. The entire tract is protected by the rib cage, spinal cord, and sternum bone. The patency of the airway is maintained by the presence of cartilages, smooth muscles, and lung surfactants.

Alveoli

• oxygen from the inhaled air is transferred into the blood and circulated throughout the body.

• Metabolic processes within the tissues produce carbon dioxide (CO2) which is then picked up by blood that is about to return to the lungs.

Lungs

• CO2 dissolved in blood is extracted and turned back into gaseous form, then exhaled through the lower and upper respiratory tracts out into the environment, thus, completing the process of breathing.

Diaphragm

• is a muscle used to expand and contract the lungs to draw air in and push air out.

• It is a large, dome-shaped muscle that contracts rhythmically and continually, and most of the time, involuntarily.

• Upon inhalation, the ____ contracts and flattens and the chest cavity enlarges

Quarter

• The air animals breathe in consists of 21% oxygen and 0.04% carbon dioxide.

• Expelled air consists of 16% oxygen and 4.4% carbon dioxide.

• This means that the lungs remove only a ___ of the oxygen contained in the air.

Tidal Volume

• Respiratory volumes are the amounts of air being moved inside and outside the lungs during breathing. By performing different types of breathing.

• During normal quiet breathing, the amount of air volume that enters and leaves the lungs is equal to 500 ml, this is termed as the

• 0 - 300 ml for animals from 1 to 25 kg,

• 300 - 1600 ml for animals from 20 to 120 kg,

• and 1600 - 3000 ml for animals from 100 to 200 kg.

30-60 breaths

• The average human respiratory rate is ____ breaths per minute at birth, decreasing to 12–20 breaths per minute in adults.

Similar subgross anatomy of the lungs

• ruminants (cattle, sheep) and pigs

• dogs, cats, monkeys, rats, rabbits, and guinea pigs

• horses and humans

Large lungs and efficient nostrils

• A horse's breathing process is similar to other mammals, involving the intake of oxygen and expulsion of carbon dioxide.

• The primary difference lies in the horse’s adaptations, such as ___ and _____, which allow them to breathe efficiently even during intense physical activity.

Mouth/Nose

Air is taken into the body

Nasal Cavity

Air then enters the ___ which lies right above the root of your mouth. From there it splits into 2 passages

Nasal Passages

These passages warm, filter, and moisten the air before it goes into the lungs

Pharynx

• is located at the back of your mouth and throat.

• The part of the pharynx used for respiration is named the nasopharynx and it connects the nasal cavity to the larynx

Larynx

• or voice box

• located behind the base of the tongue.

• It covers the trachea while so no food enters but it also makes sound through vibration + air and they are able to bark.

Trachea

• part of the upper respiratory tract.

• It is a long tube that runs from the larynx to the lungs and it splits into 2 branches.

Bronchi

• From the trachea the air gets passed into the biggest passageway in the lungs also known as the ___

• From here air is divided into smaller branches of the lung's also known as the bronchial tree.

Bronchioles

• These are some of the smallest branches of the bronchial tree.

• These branches connect through bronchi to the alveolar sacs

Alveolar Ducts

• The tiny ducts that connect air from the bronchioles to the alveolar sacs.

• Alveoli-thin like sacs surrounded by capillaries

• This is where gas is exchanged within the capillaries

Hypoxia

• In low-oxygen environments, a condition

• animals face challenges due to reduced oxygen availability relative to their cellular demands.

• To cope with low oxygen levels, animals can either migrate to areas with better oxygen supply or undergo internal adjustments.

Hypoxia

• refers to a condition in which there is a deficiency of oxygen in the tissues of an animal, despite normal blood flow.

• It can occur when an animal is unable to get enough oxygen, either from the air or from water, to meet its metabolic needs

Catfish, Eels, Nurse Sharks, Frog (Amphibian)

Several marine vertebrates have adapted to survive in low-oxygen environments, often referred to as hypoxic conditions.

Breathing in birds

Movements of the ribs and breastbone or sternum expand and compress these air sacs so they act rather like bellows and pump air through the lungs.

Gills

• Fish breathe through ___, which are specialized organs that allow them to extract oxygen from water.

• Fishes extract oxygen from the water using their gills by actively passing water over them, allowing oxygen to diffuse into their bloodstream and carbon dioxide to diffuse out.

• This system is highly efficient for underwater life, where oxygen levels in water are lower than in the air.

Breathing in fishes

• Water Inflow: Fish take in water through their mouth.

• Water Movement Over Gills: Once the water enters the mouth, it passes over the gills.

• Gas Exchange (Oxygen and Carbon Dioxide): As the water flows over the gills, oxygen from the water diffuses through the thin walls of the gill filaments into the fish's blood. At the same time, carbon dioxide (a waste product of cellular respiration) diffuses from the fish’s blood into the water.

• Water Outflow: After the water has passed over the gills and the oxygen has been absorbed, the water exits the fish.

Epiglottis

The air enters the nasal cavity and passes to the pharynx and larynx where the ___ closes the opening to the lungs during swallowing.

Gas exchange

• ---

  occurs in the alveoli of the lungs that provide a large surface area. Here oxygen diffuses from the alveoli into the red blood cells in the capillaries that surround the alveoli.

• Carbon dioxide, at high concentration in the blood, diffuses into the alveoli to be breathed out.

Air sacs

Birds have ___ for more efficient oxygen use

Gills

fish have ___ for underwater breathing,

Diaphragm

mammals have ___ for lung expansion.

Inspiration

• Ribs move up and out

• Diaphragm flattens

Expiration

• Ribs move down and in

• Diaphragm comes up