This for Bio practicles Class 11 you can use it for yourself it is about regenration in micro oraganims and hyposynthesis

1. Regeneration in
sponges, Paramecia,
Planaria, etc.
By:- Taufiq Ahamed

2. Introduction: (Initial Observation)
 Certain invertebrate aquatic animals are able to regenerate their missing parts.
This regeneration ability in some animals is so strong that if you cut the animal in
half, each half will grow to a complete a whole new animal. The tail half
regenerates a new head and the head half regenerates a new tail.
 This unusual ability also is a method of asexual reproduction for such animals.
 Regeneration abilities vary among these animals; however, they are all subject of
attention by scientists who are trying to identify the genes responsible for such
regeneration.
 The purpose of this project is to observe the regeneration ability of these animals.
I may either select sponges or planarians for my experiments because these two
are visible to the naked eye and I do not have to use microscope and complex
tools for my observations. I may also try to study the effect of one environmental
factor such as temperature or pH on the rate of regeneration.

3. Sponges:
 Sponges are the simplest form of multi-cellular animals. A sponge is a bottom-dwelling
creature which attaches itself to something solid in a place where it can find enough food to
grow. The scientific name for sponges is “Porifera,” which translates into “pore-bearing.”
 Almost all sponges pump water to obtain nutrients and oxygen. A sponge is covered with tiny
pores which lead internally to a system of canals and eventually out to one or more larger
holes. These canals exist to move water through the sponge’s body. Lining these canals are
special collar cells. The collar cells force water through the sponge which brings oxygen and
nutrients while removing carbon dioxide and waste. The collar cells are how sponges feed.
The water brings with it bacteria and other organisms which the cells capture and filter out.
 How Do Sponges Reproduce?
 Most sponges are both male and female. During mating, one sponge plays the male role while
the other plays the female role, even though both are capable of playing either role. A
sponge may play a female role one time and a male role the next time. Sperm is released by
the “male” sponge and enters the “female” sponge. After internal fertilization, larvae is
released. After floating around for a few days, they settle down and start growing.
 Sponges can regenerate the entire organism from just a conglomeration of their cells.

4. Paramecia:
 Paramecia can not regenerate missing parts like Planarians and sponges;
however they also have some unusual properties or abilities that I like to call
degeneration.
 In paramecia, if you (somehow) rotate a small area of the animal’s surface so
that the power strokes of the cilia in this area are pointing backward, then
providing that this area is about half-way between the anterior and posterior
ends (which is the plane in which these animals divide after mitosis), then
both offspring will have areas of reversed cilia; and this will be inherited by
all their offspring, without limit.
 If you fuse two Paramecia, back to back, so that they have two mouths on
opposite sides (Janus morphology) then this double body will be inherited by
both daughter cells each time mitotic divisions occur.

5. Hypothesis:
 Following are sample hypothesis for the four questions that I have proposed:
 The larger a fragment of planarian, the less it takes to regenerate.
 pH has no affect on the rate of regeneration of planarians.
 Planarians regenerate faster in darkness.
 Planarians regenerate faster in warm water.