How are water and minerals transported in plants?
Water and minerals are transported through the xylem in plants. Transportation of the water and mineral is the upward movement and is the passive process. Xylem is composed of living and non- living cells. Mainly non- living cells are present, includes tracheary elements- tracheids and vessel elements. Xylem tissue also contains xylem parenchyma cells for storage function and xylem fibres for the mechanical function. Water and minerals from the soil enter into the plant through the root and then through root cortex and finally get passed into the xylem, moves upward into the leaves and the path through which water moves into xylem cells occurs through the apoplast (transport in the cell walls to the intercellular spaces) and symplast (transport occurs from cell protoplast by the interconnection of plasmodesmata) and this upward movement of the water and the minerals from roots to the aerial parts of the plant against the gravitational force through the xylem is known as ascent of the sap.
When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.
Outline a project which aims to find the dominant coat colour in dogs.
Draw the structure for the following compounds.
(i) Ethanoic acid (ii) Bromopentane*
(iii) Butanone (iv) Hexanal.
*Are structural isomers possible for bromopentane?
A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases?
How is the sex of the child determined in human beings?
(a) What property do all elements in the same column of the Periodic Table as boron have in common?
(b) What property do all elements in the same column of the Periodic Table as fluorine have in common?
Calculate the number of electrons constituting one coulomb of charge.
What is an homologous series? Explain with an example.
Why is variation beneficial to the species but not necessarily for the individual?
A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits – blood group A or O – is dominant? Why or why not?
How would you name the following compounds?
(i) CH3 -- CH2 -- Br
(ii)
(iii)
How does the electronic configuration of an atom relate to its position in the Modern Periodic Table?
Find the power of a concave lens of focal length 2 m.
Why does the cord of an electric heater not glow while the heating element does?
Redraw the circuit of Question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to measure the potential difference across the 12 Ω resistor. What would be the readings in the ammeter and the voltmeter?
Which gas is usually liberated when an acid reacts with a metal? Illustrate with an example. How will you test for the presence of this gas?
How is a voltmeter connected in the circuit to measure the potential difference between two points?
Why does an aqueous solution of an acid conduct electricity?
What happens when dilute hydrochloric acid is added to iron fillings? Tick the correct answer.
(a) Hydrogen gas and iron chloride are produced.
(b) Chlorine gas and iron hydroxide are produced.
(c) No reaction takes place.
(d) Iron salt and water are produced.
You are given kerosene, turpentine and water. In which of these does the light travel fastest? Use the information given in Table 10.3.
Material medium |
Refractive index |
Material medium |
Refractive index |
Air | 1.0003 | Canada Balsam |
1.53 |
Ice | 1.31 | ||
Water | 1.33 | Rock salt | 1.54 |
Alcohol | 1.36 | ||
Kerosene | 1.44 | Carbon disulphide |
1.63 |
Fused quartz |
1.46 | ||
Turpentine oil |
1.47 | Ruby | 1.71 |
Benzene | 1.50 | Sapphire | 1.77 |
Crown glass |
1.52 | Diamond | 2.42 |