Xylem
What does xylem transport?
Water AND mineral ions
Which two locations does phloem send substances to?
Roots and Shoots
What is transpiration?
The evaporation of water from the surface of a plant
What is the name of the process by which water enters root hair cells?
Osmosis.
What colour is a polar bear's skin?
Black
Which specialised cells absorb water from the soil?
Root hair cells
What substances does the phloem transport?
Sucrose and amino acids.
What happens to transpiration when wind speed increases?
It generally increases because moving air removes humid air near the leaf.
Does water move from a dilute solution to a concentrated solution by osmosis, or the other way round?
From a dilute solution to a more concentrated solution, through a partially permeable membrane.
Which animal has three hearts?
Octopus
In which direction does water move through the xylem?
Upwards, from the roots towards the leaves.
True or false: Substances in the phloem can move both up and down a plant
True. Translocation can occur in either direction, depending on source and sink.
Through which tiny pores does most water vapour leave a leaf?
Stomata.
What happens to transpiration when humidity increases?
It usually decreases because the water vapour concentration gradient becomes smaller.
What is the national animal of Scotland?
A unicorn 🦄
True or False: xylems are made from hollow, DEAD cells
True
True or false: Phloem is made of living cells, including sieve tube elements.
False. The phloem is made from living cells WITH sieve tubes
What equipment can be used to estimate the rate of transpiration in a leafy shoot?
A potometer. It measures water uptake as an estimate of transpiration.
Why does increasing light intensity generally increase transpiration?
The stomata usually open in light, allowing more water vapour to diffuse out.
If you could fold a piece of paper in half 42 times, would its thickness reach the Moon?
Yes! Assuming a thickness of 0.1 mm, it would exceed 400,000 km.
Why do xylem vessels have lignin in their walls?
To strengthen the vessels and prevent them from collapsing under tension.
What do we call the process of moving substances in the phloem called?
Translocation
Name 4 factors that can affect transpiration
- Temperature, Humidity, Wind speed/air flow, Light intensity
MENTAL MATHS: A potometer bubble moves 24 mm in 3 minutes. Calculate the bubble's speed.
8 mm per minute (24 ÷ 3).
What is the most stolen food in the world, according to a widely circulated estimate?
Cheese