The document discusses several biological processes related to homeostasis, including thermoregulation, osmoregulation, excretion, and feedback mechanisms. Thermoregulation involves various systems working to maintain steady body temperature through processes like evaporative cooling and heat shock proteins in plants. Osmoregulation requires adaptations for water balance in land animals like waxy skins and drinking moist foods, while plants employ strategies like thick, waxy leaves and positioning stomata. Excretion eliminates waste through various routes in both plants like shedding leaves and animals like sweating, breathing, and urinating. Feedback mechanisms can be negative, counteracting changes, or positive, increasing changes away from set points to enable rapid responses.

1. Muzammil Siddique

2. Process Related to
Homeostasis
Thermoregulation
Osmoregulation
Excretion
Feedback Mechanism
Muzammil Siddique

3. Thermoregulation
The process of maintaining a steady body Temp.
System Involved:
 Muscular
 Integument (skin)
 Respiratory
 Circulatory
 Nervous System
 Endocrine
Muzammil Siddique

4. Muzammil Siddique

5. In Plants
Low Temperature:
•Bring changes in solutes
composition of cell
(super cool without ice
formation).
•Increasing proportion of
unsaturated fatty acid.
High Temperature:
•Evaporative cooling
•Heat-shock proteins
Muzammil Siddique

6. Muzammil Siddique

7. Osmoregulation
Land Animals:
“Drying up” is the huge problem.
Adaptations are
 Waxy exoskeletons of insects
 Layers of dead Keratinized skin cells
 Drinking and eating moist foods
 Using metabolic water(water produced during cellular
respiration) e.g. Kangaroo.
Muzammil Siddique

8. Muzammil Siddique

9. Muzammil Siddique

10. In Plants
 Hydrophytes: Extensive stomata present on the upper
surface.
 Mesophytes: Sufficient supply Stomata open
Restricted Supply Stomata close.
 Xerophytes:
Thick and small leaves
Waxy and leathery cuticle
Stomata are on the lower surface of leaves
Stem stores water
Muzammil Siddique

11. Excretion
Elimination of waste products
In Plants through:
 Leaves (shedding there leaves)
 Old xylem (store strange chemicals in xylem e.g.
ebony)
 Roots (secrete waste products e.g. conifers)
In Animals through:
 Skin ( sweat)
 Lungs (exhalation of Carbon dioxide)
 Kidney (in the form of urine)
 Liver (Detoxify poisons, produce ammonia, urea, uric
acid from nitrogenous waste, Recycle old RBC)
Muzammil Siddique

12. Muzammil Siddique

13. Feedback
Feedback compares current conditions to the body’s
comfort levels.
It has two types:
 Negative Feedback
 Positive feedback
Muzammil Siddique

14. Negative Feedback
Counteracts change and brings the body back to
homeostasis.
Negative
feedback
loop
Muzammil Siddique

15. Positive Feedback
Increases change away from the set points. Needed for
rapid change in the body.
e.g. Torn blood vessels stimulates the release of clotting
factors to stop blood flow.
Muzammil Siddique

16. Muzammil Siddique

17. Example of Positive and Negative
Feedback Loop
Muzammil Siddique

18. Muzammil Siddique