Hydra model system đŸ€©

HYDRA REPORT
20-9-19

Soon after the day of making these 5 beaker cultures, I observed my Hydras so as to see whether there is any change or growth or increase in number of Hydras or not,etc. I was amazed seeing that just after one day of making culture I got to see budding occurring in my hydras. :heart_eyes: Which certainly means they were growing happily :heart_eyes::heart: the 5 beakers are labeled as HC1, HC2
HC5. As mentioned earlier there were 3hydras in each.

So , on 20th September I observed that in,

HC1:-
Out of the 3hydras 2 showed budding :heart_eyes:


The third was fine showing movements but hadn’t started budding yet.

HC2:-

Out of the 3 Hydras in this beaker , only one showed budding with that too with an extremely small bud ,rest too being the same as the previous day.

HC3:-
In this one , I saw all the 3 Hydras floating on the surface of water and amongst those 3, two were having buds with tentacles.

HC4:-
Here in this beaker , I saw one Hydra with a bud at the bottom attached to the base of beaker

And the rest two were floating on the surface. Amongst both one was having a small bud while the another was same as previous day.

HC5:-
In this beaker all the tree showed no buds and we’re same as the previous day.

I’ll check tomorrow and see whether the buds have detached from the parent or not, and will also see it budding has occurred in those Hydras in which no bud was seen.

Pitch in guys and ask more questions (when does it float, how often does it eat, is hydra having a digestive system,etc) to get many doubts clarified. @drishtantmkawale @jtd @pratittodkar @Akshitha

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Rod and cone cells in the human retina contain proteins called opsins that change shape when light strikes them. This causes another type of protein, an ion channel, to generate an electrical signal along nerves connecting the eye to the brain – a process called phototransduction.Hydras have the same types of opsins and ion channels as we do.

Well , I’m not sure at present how would I do but yes definitely I’ll see upon this and will work out on it. Any ideas for the design @drishtantmkawale @pratittodkar and all

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Do they fire the poison every time there is a change from light to dark or just every time there is darkness? Is the poison acidic or basic and what’s it’s pH? What is the minimum water level that hydra’s need to survive? How much poison will they secrete in a single instance?

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But hydras have no brain. Do they have nerves?

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What are your future plans with these hydra?

Aren’t hydras sedentary in nature? Yet they seem to move from place to place? How exactly does their locomotion work?

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They don’t have any nerves. The hydra has a nervous system characterized by a nerve net. A nerve net is a collection of separate, but “connected” neurons. Neurons are connected by synapse(https://faculty.washington.edu/chudler/synapse.html). Communication between neurons can be in both directions at the synapse within a nerve net. The nerve net is concentrated around the mouth. Unlike higher animals, the hydra does not have any grouping of nerve cell bodies. In other words, there are no ganglia.

The hydra does have specialized cells for touch and chemical detection.
https://faculty.washington.edu/chudler/invert.html

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As I mentioned my main motto is to increase their number but want to do some interesting stuff on it 
can you design an interesting experiment using Hydras with a big objective.

Although attached to the substratum by the basal disc and usually standing erect, the Hydra has several methods of locomo­tion. Usually it bends down and attaches the tentacles to the sub­stratum with the help of the glutinant nematocysts.

It now releases and removes the basal disc to a new position and again stands up by disengaging its tentacles. This type of locomotion is known as walking. It may bend its body and perform looping movement like that of a leech (Fig. 62 A). When in a hurry, the animal runs by performing a series of somersaults (Fig. 62 B).

Methods of Locomotion in Hydra

Sometimes it walks inverted by using the tentacles as legs. Again it may glide considerably by dragging the basal disc—the cells of which have special power of throwing out pseudopodia like an Amoeba.

Occasionally Hydra secretes a bubble of gas under its basal disc and floats about by the hydrostatic action of the gas bubble. A Hydra may climb by attaching its long tentacles to a distant object. Then releasing the basal disc and contracting the tentacles the body is drawn up, and it resumes its normal position on the new substratum.

It is to be noted that:

(1) Fixation is effected by the mucus- secreting gland cells in the epidermis of the basal disc and the glutinant nematocysts with sticky threads on the tentacles.

(2) Shortening the length of the body is due to the contraction of the muscular processes of the ectodermal epitheliomuscular cells.

(3) Increasing the length of the body is produced by contracting the muscular processes of the endodermal nutritive-muscular cells.

http://www.biologydiscussion.com/zoology/hydra/hydra-habitat-locomotion-and-reproduction-zoology/49465

Well , this was indeed a good question as I too got to know it’s locomotion just now after searching upon it 
thanks @Akshitha

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I didn’t got any update on this. @Sjuday2527 please tell what do you think about it?

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What is your expectations today? @Sjuday2527?
Are the number of hydra increased?
Are the hydra having buds?
How many beakers/tanks of hydra are present?
What is the total count of hydra?

What is your feeding regime? How many moina in beakers, how many in tanks?

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Actually I searched on this a long time back but couldn’t find any information, well now I have got one stating,

Hydra have been classical model organisms for over 250 years, yet little is known about the toxins they produce, and how they utilize these toxins to catch prey, protect themselves from predators and fulfill other biological roles necessary for survival. Unlike typical venomous organisms the hydra allomonal system is complex and “holistic”, produced by various stinging cells (in the hunting tentacles and body ectoderm) as well as by non-nematocystic tissue. Toxic proteins also fulfill novel, non-allomonal roles in hydra. This review described the toxins produced by hydra within the context of their biology and natural history. Hydra nematocyst venom contains a high-molecular weight (>100 kDa) hemolytic and paralytic protein and a protein of approximately 30 kDa which induces a long-lasting flaccid paralysis. No low-molecular weight toxicity is observed, suggesting the lack of “classical” 4-7 kDa neurotoxins. The occurrence of a potent phospholipase activity in the venom is supported by the detection of several venom-like phospholipase A2 genes expressed by hydra. Hydra also produce toxins which are not part of the nematocyst venom. In the green hydra, Hydralysins, a novel family of Pore-Forming Proteins, are secreted into the gastrovascular cavity during feeding, probably helping in disintegration of the prey. Other putative non-nematocystic “toxins” may be involved in immunity, development or regulation of behavior. As the first venomous organism for which modern molecular tools are available, hydra provide a useful model to answer many outstanding questions on the way venomous organisms utilize their toxins to survive.

Well, I have kept them in a 250ml beaker with 100ml of DC water filled. The less will be the water the easier it would be to catch it’s pretty moina. It shouldn’t be even too less, at present what’s this too less, I don’t know but yes in 100 ml there’s no problem to the Hydras that’s what I can see as they are increasing in number day by day.

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Apologies for the late response


As I mentioned earlier, I had made 5 beaker cultures of Hydra each having 3hydras on 19-6-19.
At present on Friday’s (27-9-19) count ,

HC1 - 9 hydras
HC2 - 12 hydras
HC3 - 8 Hydras
HC4 - 13 Hydras
HC5 - 15 hydras.

My feeding pattern was around 4 moinas to each hydra. So in the starting i.e. on 19-9-19 I had put approximately 12-15 moinas in each beaker which means every Hydra would have got 4-5 moinas.

Updating about the tank culture which I had missed to mention, I had prepared this tank culture of Hydra just a day before these beakers were made i.e on 18-9-19 .

I had put 5hydras in it and had given them approximately 40-50 moinas just with a logic that they would eat more and grow faster in a tank .
But the next day i.e on 19-9-19 I observed that there were only 2 Hydras :fearful:I was thinking where did the rest of the 3hydras go ???
But when I saw the count of moinas there were just 1 or 2 left. I feeded them again and after 2 days I saw 4 :star_struck: I was happy at least they are increasing now. After a few days on 26-9-19 I put some algae from a previous tank so that this algae doesn’t allow the debris to be accumulating. Even if you see in moina cultures with algae, you won’t be finding debris. But why ? What does algae feed on ???

This is the picture after inoculation of algae in my tank.

Presently on 27-9-19 the count in the tank was 17 :heart_eyes: which is good to see that they are increasing.

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I’m also attaching a picture of my log book from 19-9-19 to 24-9-19.

As you all can see here there is another beaker HGEC (HYDRA GROUP ELPHINSTONE COLLEGE)
which they had made in the last workshop , I’m feeding that beaker too and I’m seeing increase in number in that beaker too
I have 2more beakers which @jaikishan used to maintain I’ll send their pic as well by tomorrow. Those 2beakers have 35 and 28hydras respectively.

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What is the status of hydra today in beakers and tank? What is the expectation? What is observation of today?

@Sjuday2527 looking forward to report on hydra and other model systems.
what is the status of moina, nematodes, rotifers?

We can study molecular mechanism involved in regeneration @Sjuday2527

I along with my collaborators @Parab96k1 @Neha2 have done some experiments on regenerative performance of symbiotic Hydra viridissima under light and dark conditions. Why not look for more preliminary aspects of research with respect to chlorohydra?

What repair mechanism does Hydra follows for regenerating?