Multicellular Organisms Flashcards
A on the next test surelyyyyyy (18 cards)
What are the three key features that maximize the efficiency of exchange surfaces?
Thin, Moist, Large surface area
Each feature enhances the transfer of substances across membranes.
Why is thinness important for exchange surfaces?
It allows substances to transfer more easily across a membrane.
Thicker layers make it harder for substances to move.
How does moisture contribute to the efficiency of exchange surfaces?
Moisture makes membranes more flexible and aids diffusion and osmosis.
Moist membranes facilitate the movement of substances.
What is the significance of a large surface area in exchange surfaces?
It allows for faster movement of substances across the surface.
Larger areas enhance the rate of exchange.
What role does the respiratory centre in the brain play?
It detects CO2 buildup and stimulates breathing.
This is crucial for maintaining proper gas exchange.
List the components of the human respiratory system.
- Nasal Cavity
- Epiglottis
- Trachea
- Cartilage rings
- Bronchus
- Bronchioles
- Alveoli
- Diaphragm
Each component plays a specific role in respiration.
What happens during inhalation?
Muscles contract, increasing chest cavity volume and decreasing pressure.
This process allows air to flow into the lungs.
What is the process of expiration?
Muscles relax, and air is expelled from the lungs.
Abdominal muscles can assist in expelling air during exercise.
What is oxy-haemoglobin?
Oxygen attached to haemoglobin in the blood.
This compound is essential for oxygen transport in the body.
How is carbon dioxide transported in the blood?
Both dissolved in plasma and attached to haemoglobin.
This dual method aids in efficient gas exchange.
What are the features of alveoli that facilitate gas exchange?
Thin, moist, and large surface area.
These features maximize diffusion and exchange of gases.
True or False: Gases move from areas of low concentration to areas of high concentration.
False
Gases move from high concentration to low concentration via diffusion.
What are some factors that impair normal lung function?
- Asthma
- Bronchitis
- Hay fever
- Emphysema
- Pneumonia
- Carbon Monoxide
Each condition affects the efficiency of gas exchange.
What is the role of stomata in plants?
They control gas exchange in the leaf.
Stomata can open or close depending on the turgidity of guard cells.
How do guard cells control the opening and closing of stomata?
By absorbing or losing water, becoming turgid or flaccid.
This process regulates gas exchange and transpiration.
What is transpiration?
The process by which moisture is carried through plants and released as vapor.
It occurs through the stomata and is essential for water regulation.
List the factors affecting transpiration rates.
- Light
- Temperature
- Relative humidity
- Wind and air movement
- Soil-moisture availability
- Type of plant
Each factor influences how much water a plant loses.
Fill in the blank: Transpiration is essentially _______ of water from plant leaves.
evaporation
This process helps in nutrient transport and temperature regulation.
