Xylem Function and Plant Physiology

The video explains how trees transport water from roots to leaves, focusing on root pressure, osmosis, and active transport. It discusses the role of xylem and transpiration in water movement and how different xylem vessel adaptations affect tree growth and longevity. The video also highlights the risks of embolisms in wider xylem vessels and their impact on water transport.

What causes root pressure in trees?

• Higher mineral concentration in the soil

• Active transport of water

• Higher mineral concentration in the roots

• Evaporation of water from leaves

How do minerals enter the roots of a tree?

• Through osmosis

• Via active transport

• By diffusion

• Through transpiration

What is osmosis?

• Movement of solvent across semi-permeable membranes

• Movement of solute from high to low concentration

• Movement of air through xylem

• Movement of water from high to low concentration

What role does the xylem play in trees?

• It absorbs sunlight

• It stores nutrients

• It transports water

• It produces leaves

What happens when stomata open?

• Water is absorbed by roots

• Minerals are transported to leaves

• Air enters the xylem

• Water evaporates from leaves

What is a potential downside of wider xylem vessels?

• Higher risk of embolisms

• Increased water transport

• Faster growth rate

• Longer lifespan

Why should freshly cut flowers be placed in water quickly?

• To speed up their growth

• To increase their fragrance

• To enhance their color

• To prevent air pockets in the xylem

What can cause embolisms in trees?

• Dry spells and insufficient soil moisture

• Excessive water absorption

• Rapid leaf growth

• High humidity levels

How do narrower xylem vessels benefit trees?

• They increase water transport speed

• They promote faster growth

• They enhance mineral absorption

• They reduce the risk of embolisms

What is a common characteristic of trees with slower growth rates?

• Increased transpiration rate

• Higher mineral concentration in leaves

• Narrower xylem vessels

• Wider xylem vessels