Chapter 4 Flashcards
Where do special cells called root hair grow out of
Surface of roots.
How does root hair absorb minerals along with water?
It passes through the cell wall and the cell membrane of the cell, and into the cytoplasm.
What is a xylem vessel
A vessel which transport water and mineral ions up the plant
Describe the structure of xylem vessels
they are long, tube like cells. THey are dead cells-all of their contents such as cytoplasm and nucleus have dissapeared.
All that is left is their cell walls with empty space inside.Connects the roots to the highest parts of the plant.
Describe a process of how water moves through the leaves.
When water arrives at a leaf, it moves out the xylem vessels into the leaf cells. The cells that have chloroplasts use some of the water for photosynthesis. But they do not need very much water for that.
The liquid water in the cell soaks into the cellulose cell wall, and then changes to water vapour and evaporates. It diffuses into the air spaces between the cells.
The air spaces connect with the air outside the leaf through tiny holes called stomata.
The loss of water vapour from leaves is called
transpiration
What happens when a plant cell doesn’t contain enough water?
It becomes soft and floppy and collapses. It becomes wilted because they need water to stay strong and firm and well supported.
How is water important for plants?
Water can be used for transport,cooling(When water evaporates and takes heat with it) and photosynthesis
What is excretion
Getting rid of waste materials inside the body.
Give examples of substances that gets rid from excretion
carbon dioxide, urea, excess water
Where does the protein broken down from food go after the digestive system.
Any proteins in food are broken down to smaller molecules inside the digestive system. They go into the blood, the blood brings them into the liver
What happens if we get more protein than we need?
the liver changes the smaller molecules into urea( a poisonous substance). The urea is removed from the blood by the kidneys in the excretory system. This system is also known as the renal system
Is Urea a poisonous substance?
Yes
What happens if urea builds up in the body?
it makes a person ill
How is urea removed
from the blood by the kidneys in the excretory system.As the blood flows through the kidneys, the kidneys filter the blood. They remove all of the urea from it.
The urea dissolves in the excess water removed by the kidney from the blood.The solution becomes urine.
The urine made in each kidney flows down a tube called a ureter.This carries it to the bladder. The urine flows out of the bladder to the outside world through another tube called urethra
