21 Questions
What is the primary reason why terrestrial organisms were able to increase their uptake of oxygen?
Because oxygen is more concentrated in air
What is the function of spiracles in insects?
To provide a direct path for air to enter their system
What is the purpose of tidal ventilation in vertebrates?
To move air with high O2 in and air with high CO2 out
Why is it easier to pump oxygen in air compared to water?
Because it requires less energy to pump oxygen in air
What is the function of tracheae in insects?
To ventilate air directly to the cells
What is the primary mechanism of gas exchange in the respiratory system?
Diffusion
What is the primary function of the gills in fish?
To extract oxygen from water
What is the term for the movement of fluids down a pressure or temperature gradient?
Bulk Flow
What is the name of the thin, sheet-like structures that extend up from each gill filament and are lined with capillaries?
Lamellae
What is the term for the mechanism by which dissolved gases or electrolytes in one closed system are diffused into a second system using diffusion?
Counter Current Exchange
What is the primary difference between blood and hemolymph?
Blood is used in closed circulatory systems, while hemolymph is used in open circulatory systems
What is the primary function of the diaphragm during inhalation?
It moves posteriorly and expands the lungs
What is the term for the amount of air you generally breathe at rest?
Tidal volume
What is the function of the larynx in the throat?
It helps in separating swallowing from breathing
What is the purpose of the surfactant in the alveoli?
To reduce mucus surface tension
What is the function of the carotid bodies and aortic bodies?
To detect variation in CO2, H+, and O2 in the blood
What is the term for the percentage of red blood cells in your blood?
Hematocrit
What is the finest subdivision of the secondary bronchi?
Terminal bronchioles
What is the function of the pulmonary capillaries?
To supply each alveolus with blood
What happens to the diaphragm during exhalation?
It moves anteriorly and contracts the lungs
What is the term for the ability of a substance to be dissolved in water?
Solubility
Study Notes
Respiratory System
- Gas exchange in large organisms depends on two processes: diffusion (movement from high to low concentration) and bulk flow (movement of fluids down a pressure or temperature gradient)
- Respiratory system has two main components: diffusion and bulk flow
- Diffusion: gases move from high pressure to low pressure, dependent on partial pressure (P)
- Bulk flow: moves environmental medium across specialized respiratory surface and circulatory fluid (blood or hemolymph) through the body
Blood vs Hemolymph
- Blood: circulatory fluid in closed circulatory systems containing blood cells that deliver oxygen
- Hemolymph: fluid that many invertebrates use to circulate oxygen and/or nutrients through an open circulatory system
Respiration
- Gas exchange occurs in respiratory organs such as gills, lungs, or tracheae
- Gills: extract oxygen from water using thin, sheetlike structures (lamellae) with capillaries that bridge an artery to a vein
- Counter-current exchange: mechanism by which dissolved gases or electrolytes in one closed system are diffused into a second system using diffusion
Terrestrial Respiration
- Terrestrial organisms can increase oxygen uptake by ~50x due to higher oxygen concentrations in air
- O2 in air diffuses ~8000x faster than in water
- Water is 800 times more dense and 50 times more viscous than air, requiring less energy to pump oxygen
Insect Respiration
- Insects use spiracles (openings along the sides of their abdomen) to provide a direct path for air to enter their system
- Network of tracheae (branching tubes) ventilate air directly to their cells
Vertebrate Respiration
- Tidal ventilation: lungs inflate and deflate to move air with high O2 in and air with high CO2 out
- Inhalation: air enters the lungs, lungs expand, and the diaphragm moves posteriorly
- Exhalation: gases leave the lungs, the lungs contract, and the diaphragm moves towards the head
Respiratory System Anatomy
- Mouth and nasal passages
- Larynx: organ in the throat made of cartilage, containing vocal cords, and helps separate swallowing from breathing
- Trachea: central airway leading to the lungs
- Primary bronchi: fork in the trachea that goes to each lung
- Secondary bronchi and bronchioles: finer subdivisions of the secondary bronchi
- Terminal bronchioles: less than 1 mm diameter
- Respiratory bronchioles: lead to alveoli where gas exchange takes place
- Alveoli: sacs where gas exchange takes place
- Pulmonary capillaries: supply each alveolus with blood, allowing for rapid diffusion of gases
Control of Breathing
- Carotid bodies: sensors in the carotid arteries that detect variation in CO2, H+, and O2 in the blood
- Aortic bodies: sensors in the aorta that detect variation in CO2, H+, and O2 in the blood
- They send signals to the brainstem, which sends action potentials to motor neurons that control breathing rate
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
