cordination in plants

1. Plant coordination

2. • -----is the gland which is responsible for development of immune system
• Emergency hormones secreted by adrenal glands are-------
• -------is the specialised cells in pancreas which helps to secretion of
pancreatic hormone
• Major hormones of pancreas-----
• Function of insulin is to-------
• Glucagon helps in ---
• Deficiency of insulin leads to -----
• Diet of diabetic patient should be---

3. • Hormone produced by testis
• Functions of testis are----
• Hormone responsible for pubertal changes in male----and in female
is----
• Hormones secreted by ovary are-----
• -----called as pregnancy hormone

4. Which of the following is not an endocrine gland?
A.Adrenal Glands
B.Salivary Glands
C.Pineal Glands
D.Pancreas

5. Coordination in plants
Immediate response to stimulus
• Nastic movement:
• The movement of a plant part in response to an external stimulus in
which the direction of response is not determined by the direction of
stimulus is known as Nastic movement

6. Examples of nastic movement
• 1)In the Mimosa pudica plant,
when we touch the leaves of
the plant they fold up. Here the
stimulus is touch.
They change shape by changing
the amount of water in them
resulting in swelling /shrinking –
shape change

8. Tropic movement
Plant shows some growth movement in response to a stimulus, which
is specific and depends on the direction of the stimulus.

9. Tropic movement
Stimulus for tropic movement
• Light-phototropism
• Gravity-geotropism
• Contact-thigmotropism
• Water source-hydro tropism
• Chemicals-chemotropism

10. • Tropic movement towards
stimulus-positive
• Tropic movement away from
stimulus-negative

11. Phototropism
• Movement of plant towards light
• Shoot-positive phototropic
• Root-negative phototropic

12. Hydrotropism
• Movement of plants towards
water source
• Root-positive
• Shoot-negative

13. geotropism
Plant movement in
response to force of
gravity is called
geotropism

14. Thigmotropism
• Plant movement in
direction of solid that
touches
• Eg: movement of tendrils

15. Chemotropism
• chemotropism The growth or
movement of a plant or plant part in
response to a chemical stimulus
• The growth of pollen tube towards a
chemical which is produced by an ovule
during the process of fertilization in a
flower.

17. • What is ‘hydrotropism’? Describe an experiment to demonstrate
‘hydrotropism’.
‘Hydrotropism’ is the directional growth of a plant part in response to
water. For example, roots show hydrotropism as they grow towards
water in the soil and are positively hydrotropic.
An experiment to demonstrate hydrotropism is as follows:

18. • A porous pot filled with water is taken and inserted in a tub filled with
dry sand.
• A freshly germinated pea seedling is sowed in the sand.
• As water is not available in sand, the root growing will bend towards
the porous pot filled with water.
• A hydrotropic curvature of the root is observed as it grows towards
water.
• This bending of root shows the movement in response towards water.

19. PLANT HORMONES
• Also called phytohormones
• Phytohormones are chemical
compounds which are released
by stimulated cells.
• These hormones are diffused
around the plant cells.
• They have a role to play in the
• cell division,
• cell enlargement,
• cell differentiation,
• fruit growth,
• falling of leaves,
• ripening of fruits,
• ageing of plants

20. Types of phytohormones
• Auxins
• Gibberellins
• Cytokinin
• Abscisic acid
• ethylene

22. Auxins
• They help in the
cell growth at the
shoot and root
tips.
• By elongating
the cells, they
help in the
growth process
• Helps in coiling of tendrils
• When a tendril comes in contact with any
support, the part of the tendril in contact with
the object does not grow as rapidly as the part
away of the tendril from the object.
• This cause the tendril to circle around the object
and thus, cling to it.

23. auxin
• Helps in phototropism
• Auxin moves to the darker side of the plant, causing the cells there to
grow larger than corresponding cells on the lighter side of the plant. .
• The redistribution causes the cells on the shaded side to elongate more
than those on the side with the light shining on them.
• This produces a curving of the plant stem tip toward the light, a plant
movement known as phototropism.

24. Gibberellins –
• These hormones are responsible for the cell growth in
the stem,roots, seed germination, and flowering.

25. • Cytokinin
• They promote cell division in plants.
• Cytokinin are naturally synthesized in the plants where rapid cell
division occurs e.g. root apices, shoot buds, young fruits

26. • Abscisic acid
• This hormone inhibits the growth of the plant. And therefore, it
promotes dormancy in seeds and buds.
Function:
• The detachment of fruits, flowers
• falling of leaves/wilting

27. Ethylene
• It acts as a growth promoter as well as an
inhibitor.
• Occurs in gaseous form.
• It is synthesized in the ripening fruits and
tissues undergoing senescence(condition
or process of deterioration with age).
• Widely used in agriculture
• Inhibitory role:
• Ethylene promotes abscission in
senescent leaves and fruits,
• (senescence:cells power to
divide and grow will loss due to
ageing

28. How is the movement of leaves of the sensitive
plant differ from the movement of shoot towards
light?

29. What are the plant hormones

30. How do auxins responsible for movement of
tendril

31. Why is the use of iodine is advisable

32. How does our body respond when adrenaline
is secreted into the blood

33. Why are some patients of diabetes treated by
giving injection of insulin?

34. How does phototropism occurs in plants

35. Which signals get disrupted in case of spinal
cord injury?

36. How does chemical coordination occur in
plants

37. What is the need for a system of control and
coordination in an organism?

38. What is the difference between the movement takes
place in sensitive plant and movement in our legs

39. How involuntary actions and reflex actions
different from each other?

43. d

44. b

45. Ans:b

46. Features associated with puberty are mainly
because of secretion of

47. Why chemical communication better than electrical impulses
as a means of communication between cell in multicellular
organisms
• nervous impulses are quick. Even though they have some limitation.
Electrical communication is limited to only those regions which are
connected by nerves. Before generating new impulses cells take time to
rest, in general the cells cannot generate and transmit the nervous impulse
continuously. this is why they are opting chemical coordination
• chemical coordination can take place throughout the body through
blood(the required cells will take it as per requirement)
• Chemical communication can be done steadily & persistently and it will
last long. whereas nervous coordination can be done only at intervals.

48. • Smita’s father has been advised by a doctor to reduce his sugar intake.
• Name the disease he is suffering from and name the hormone whose deficiency
is? ,
• Identify the gland that secretes it and mention the function of this hormone.
• Explain how the time and amount of secretion of this hormone is regulated in
human system.
• Answer.
• He is suffering from diabetes. Deficiency of insulin causes diabetes.
• Pancreas secretes insulin. Insulin helps in regulating blood sugar.
• When the sugar level in blood increases, it is detected by the a-cells of the
pancreas which responds by producing more insulin. As the blood sugar level
falls, insulin secretion is reduced.

49. • State the function of:
(i) gustatory receptors, and
(ii) olfactory receptors.
Answer.
(i) Gustatory receptors – these are sensitive to taste
(ii) Olfactory receptors – these are sensitive to smell.