Human Gas Exchange System Flashcards
1
Q
How does oxygen enter the lungs?
A
- Trachea walls contain incomplete C-shaped rings of cartilage that keeps the tubes permanently open
- Trachea divides into 2 bronchi
- These divide many times to form tree of smaller bronchi
- Bronchioles are the smallest final divisions of the bronchi
- These end in clusters of air sacs called alveoli where gas exchange occurs
2
Q
What is the definition of Gaseous Exchange?
A
- The movement of gases by diffusion between an organism and its environment across and barrier eg. alveolus wall
- Oxygen passes from the air in the alveoli to the blood in the capillaries
- Carbon Dioxide passes from the blood to the air in the alveoli
3
Q
What are Ciliated epithelial cells and their function?
A
- Cells line the airways of respiratory system and female reproductive system
- Hair like structures which beat in rhythm to move mucus and trapped pathogens from lungs and airway
- They also move the egg from ovary to the uterus
- Columnar in shape
4
Q
What are Squamous epithelial cells and their function?
A
- Lines the inner surface of blood vessels and forms a wall of alveolar sacs in the lungs
- Facilitates diffusion of gases and small molecules
- Flattened thin shape which forms a layer one cell thick held tightly together
- Large thin surface area
5
Q
What is the importance of Surfactant?
A
- Detergent-like substance which is secreted coating alveolar surfaces
- It decreases tension
- Without the walls would stick together during exhalation and wouldn’t inflate properly
- Premature Babies born before surfactant producing cell is made have lungs that do not inflate properly
6
Q
What is the role and structure of Goblet Cells?
A
- Secrete mucus
Scattered among ciliated epithelium - Don’t have cilia
- Nucleus found towards the basal layer of cell
- Large Golgi Apparatus
- Mucus is viscous and traps harmful substances forming a physical barrier
- Reduces chance of infection
7
Q
smooth muscle
cartilage
A
