Detail about Homeostasis,There are three important aspects of homeostatis. Osmoregulation Thermoregulation Excretion

1. HOMEOSTASIS
Chapter 1

2. HOMEOSTATIS
• Home means same and statis means state.
• The regulatory mechanism which maintained the internal environment of a
organism is called homeostatis.
• Organisms use homeostasis to maintain a “steady state” or internal balance
regardless of external environment
• In humans, body temperature, blood pH, and glucose concentration are each
maintained at a constant level
Important Aspects of Homeostatis
There are three important aspects of homeostatis.
– Osmoregulation
– Thermoregulation
– Excretion

3. HOMEOSTATIS
• Osmoregulation:: The regulatory mechanism which maintain the balance
between water and solute context of a cell is called osmoregulation.
Excretion: The removal of harmful substance produce in the metabolic process
from the body is called Excretion.
Thermoregulation: The maintained the temperature of the body with in a range
is called thermoregulation.

4. HOMEOSTATIS• Feed Back System: The body check and balance system.
• 3 organs are involved.
• 1. Receptor :
• which receive any change in the internal environment of the
body are called Receptor.
• 2. Effector :
• The central nervous system which send the message to a
particular organ are called effector. Take part in particular
action.
• 3. Central Nervous System
• The receptor transfer message to a central nervous system
such as brain.
Stimuli---- Receptor ------brain
Send msg to
CNS----------------------organ
Stimuli---- Receptor ----------Brain(CNS)-------Effector------------particular organ

5. HOMEOSTATIS

6. TYPES OF FEED BACK SYSTEM
•
There are two type of feedback system.
• Positive Feed Back System
• Negative Feed Back System
•
1. Positive Feed Back System
When there is a change in the internal environment and it is
further increase by the process are called positive feedback
system.
• 2. Negative Feed Back System
When there is a change in the internal environment and it is
further decreased by the process called negative feedback system.

7. POSITIVE & NEGATIVE FEED BACK SYSTEM

8. OSMOREGULATION
• The regulatory mechanism which maintain the balance between water and solute
context of a cell is called osmoregulation.

9. OSMOREGULATION IN PLANT
Due to the availability of water there are four groups of plant.
• Hydrophyte
• Halophyte
• Xerophyte
• Mesophyte

10. HYDROPHYTE : Fresh water plant group.
• Characteristic of Hydrophyte
• Have soft body without cuticle.
• The leave have stomata in the upper surface with take part in transpiration.
• Root : either absent or poorly developed.
• Function: water absorption
• Have Submerged Leaves: Function: Transpiration
• Contain hydathodes(opening without guard cells)
• Example
Hydrilla, Lotus, Lily plant

11. • HALOPHYTES Marshy soil or salty soil plant group.
• Characteristic of Halophyte
• These plant absorb water from such a soil, in which (oxygen disappears) & have
higher salt concentration and low water potential.
• Respiratory roots: due to absence of soil oxygen, plants produce special roots in the
air to absorb oxygen known as respiratory roots.
• Halophyte actively absorption salt into their roots. (exosmosis take place)
• In the leaves of plants salt glands are present which helps in the removal of salt and
water from the body.
•

12. HALOPHYTES
• Some halophytes absorb humidity by leave.
• Salt glands: present in leaves:
• Fun: remove salts and water from body.
• Example : Glass wort, Cord grass

13. MESOPHYTE: Well watered soil plant group
• Characteristics of Mesophyte
• Roots: well developed.
• Cuticle: body is covered by a layer cuticle.
• Stomata: contain stomata for evaporation of extra water.
• Guttation: Some mesophyte excrete out water in the form of drop
this process is called guttation.

14. • XEROPHYTE Dry places plants group
• Characteristic of Xerophyte
• Some plants do not face dry consition and produce seed are called ephemeral
plant. During raining season seeds germinate.
• Roots: well develop which go deep into the soil to absorb water.
• Horizontal root: Some plant have horizontal root on the surface to absorb rain
water rapidly.
• Leaves Some plant leaves are modified into spine to prevent transpiration.
• Stem & leave: covered by cuticle.
• Some plant store water in cell (succulent) Example : Cacuts, Euphorbia.
Spine

15. EXAMPLE OF XEROPHYTE

16. EXCRETION IN PLANTS
• Excretion: removal of harmful substances, produced in metabolic processes.
• Metabolic processes is slow & waste products are produced in less amount
• These products are not accumulated in plant body, they are used again in their
anabolic processes.
• Mostly CHO are used in metabolic processes, so Co2 and water are produced.
These products are not very harmful.
• The substances which are produced in excess amount are
• 1.Water 2. CO2 & O2 3.Ions

17. A. REMOVAL OF WATER: BY 2 METHODS
1. Transpiration: When extra amount of water is removed from the plant body in the form of vapors
is called transpiration. Mostly transpiration take place through stomata of leaves.
2. Guttation: when water is removed from plant body in the forms of small drops, the process is
called guttation
3. Guttation: occurs by special opening called Hydathodes. These are opening without guard cells
present on the tip or margin of leaves.
4. Guttation: occurs in plant which grow in Tropical Rain Forests
5. Where rate of absorption is high because there is high rain fall And due to humidity in air , the
rate of transpiration is low.
Note : what are Guard cells?
which regulate its opening and closing of stomata

18. TRANSPIRATION

20. HYDATHODES
Hydathodes:
Guttation occurs by special opening
called Hydathodes

21. DIFFERENCES B/W TRANSPIRATION & GUTTATION

22. RELEASE OF OXYGEN (O2) & CARBON DIOXIDE (CO2)
• In the presence
of sunlight the plants use Co2 for
photosynthesis & release O2 but in
the absence of light there is no
photosynthesis& during respiration
the plant use O2 & release Co2.

23. DAY AND NIGHT GASE EXCHENGES MECHNISM IN PLANTS

24. IONS
• In plants body excess
amount of ions are combined with the
organic compounds then they are
deposited in dead cells of the body such
as heartwood & bark or sometime in
other cells of the body.
Bark is the outermost layers of stems and
roots of woody plants.
heartwood

25. – Stomata open and close when guard cells change shape.
– When stomata are open, water evaporates and gas
exchanges.
– Stomata close at night and when plant loses too much
water.
guard cells stoma
• Guard cells surround each stoma.

26. GUARD CELLS & STOMATA: Pores for gas exchange

27. THERMO-REGULATION IN PLANTS
• Thermoregulation: The maintained the
temperature of the body with in a range is
called thermoregulation.
• Plant temp: Normal range: 10 C to 35 C.
• Low & high temperature both have great
influence upon metabolic processes of cell
as well as cell membrane.

28. THE ADAPTATION OF PLANTS
• Low temperature
– Crystalline structure
– Ice –crystals
– Freezing tolerance.
1. At low temperature the fluid nature of cell membrane is change.
The lipids of membrane are changed into crystalline structure due to which transports of solutes
through the cell membrane becomes slow .To control this conditions unsaturated Fatty acid are
produced in plant cells which stope crystal formation.

29. THE ADAPTATION OF PLANTS
2. At freezing points temperature Ice crystals are formed in the cells but ,the plants cold region
change the composition of solutes of cells So the ice crystals are not formed in cytoplasm,
but they may be formed in cell wall.
This condition is known as Freezing tolerance.
Below freezing point the cytoplasm become very cool but crystal are not produced in it.

30. HIGH TEMPERATURE
• Has more bed effects on plants.
• Destroys enzymes –results –stop metabolic processes.
• Transpiration: In high temperature: plants start rapid transpiration to decrease the temperature.
• Due to hot & dry climate there is shortage of water in plant ,so stomata are closed to stop transpiration.
• At above 40c temperature certain heat shock proteins are produced in plant body .
• Function of heat shock protein: protect enzymes from destroying and denaturing.

31. HIGH TEMPERATURE
• Shiny cuticle: in some plants shiny cuticles are present.
• Function: protect plant from high temperature.
• In some plants leaves are reduced in size.
• Sometime wilting of leaves occurs to avoids the high temperature.

32. OSMOREGULATION IN TERRESTRIAL ANIMALS
• In land animals Excretion of water take place through body surface.
• Arthropods and vertebrate are considered as the most successful animals which
can properly maintain osmoregulation. their characters for osmoregulation are
as follow
– Waterproof external body covering.
– Storage & excretion of solid waste.
– Use of Metabolic water
– Storage of dissolved materials.

33. WATER PROOF EXTERNAL BODY COVERING
• In vertebrate animals like Reptiles , birds and mammals water proof epidermis
layer is present , which prevents the loss of water from their body. The insects &
other Arthropods also contain waterproof external covering on their body.

34. STORAGE & EXCRETION OF SOLID WASTE
• In birds, reptiles and insects harmful nitrogenous substances are produced in the
form of uric acid.
• Uric acid; water insoluble, stored in cloeca for a short time.
• In cloeca its water is reabsorbed & used in the body .
• The uric acid is excreted out of the body in the form of paste or crystals

35. USE OF METABOLIC WATER
• In some mammals fat are converted into simpler compounds, as a result of this
process water is produced which is reused in the body. In this way these animals
use Metabolic water. E.g. Camel, Rat, Kangaroo

36. STORAGE OF HARMFUL DISSOLVED MATERIALS
• In mammals some urea is stored in their kidney , due to the concentration more
water is reabsorbed by the kidney.