What are the components of the transport system in highly organised plants?
Transportation in plants:- There are two components for the transportation in highly organised plants. Transportation of some materials like gases, water, minerals, organic solutes in the form of food, hormones occurs by these two components- xylem and phloem.
Xylem:- transportation of water and minerals occurs through the xylem. Water and minerals are absorbs from the soil and then by the roots, transport it to the tip of growing stem in the sequential manner. This uptake of water and minerals followed by some processes like osmosis, diffusion. Water and minerals are transported through the root hair to the cortex and then to the leaves by the two pathway apoplast and symplast by the root pressure and the transpirational pull activity. This process is unidirectional.
Phloem:- Phloem helps in transportation of food in the form of organic solutes from leaves to the storage organs of the plant and to all parts of the plants, this process is known as translocation. Food is transported through the sieve elements of the phloem and needs metabolic energy to transport the food. They use this metabolic energy in the form of ATP and by the process of osmosis water enters in the sieve tubes that raise the pressure in the phloem and then the food is transported to the parts of the plants. Transportation of food movement involves along the turgor pressure gradient that is induced by maintained gradient of water potential. This process is multidirectional.
Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?
How is the amount of urine produced regulated?
What criteria do we use to decide whether something is alive?
What are the different ways in which glucose is oxidised to provide energy in various organisms?
The breakdown of pyruvate to give carbon dioxide, water and energy takes place in
(a) cytoplasm. (c) chloroplast.
(b) mitochondria. (d) nucleus.
What are the differences between autotrophic nutrition and heterotrophic nutrition?
What are outside raw materials used for by an organism?
What would be the consequences of a deficiency of haemoglobin in our bodies?
What advantage over an aquatic organism does a terrestrial organism have with regard to obtaining oxygen for respiration?
What processes would you consider essential for maintaining life?
Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
What is a good source of energy?
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What changes can you make in your habits to become more environment-friendly?
What is the difference between a reflex action and walking?
What is the importance of DNA copying in reproduction?
If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?
Why should a magnesium ribbon be cleared before burning in air?
Define the principal focus of a concave mirror.
You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram.
Which of the following is a plant hormone?
(a) Insulin
(b) Thyroxin
(c) Oestrogen
(d) Cytokinin.
Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices.
A concave mirror produces three times magnified (enlarged) real image of an object placed at 10 cm in front of it. Where is the image located?
What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?
How do Mendel’s experiments show that traits may be dominant or recessive?
Explain the nature of the covalent bond using the bond formation in CH3Cl.
Nitrogen (atomic number 7) and phosphorus (atomic number 15) belong to group 15 of the Periodic Table. Write the electronic configuration of these two elements. Which of these will be more electronegative? Why?
How many structural isomers can you draw for pentane?
Where should an object be placed in front of a convex lens to get a real image of the size of the object?
(a) At the principal focus of the lens
(b) At twice the focal length
(c) At infinity
(d) Between the optical centre of the lens and its principal focus.