|MadSci Network: Genetics|
This has got to be the most interesting set of questions I've had. Ok, I'll tell you what I think but these are only my opinions. 1 Amoeba blob question. An amoeba is a single celled organism which moves about. The largest single cell in the world is an egg. Now, the Ostrich egg is the biggest bird egg and the only one bigger than thart would be that of the Basking shark. I don't know if any of the dinosaur eggs were bigger than this but all these egss have fairly hard outsides to protect them from damage. An amoeba is tiny and has only a cell membrane. The cell membrane would not be thick enough to protect a huge amoeba if it moved about and it wouldn't be able to hold the inards inside if there were too many inards. Perhaps a more plausable monster would be something like a slime mould. These move about and are congregations of many cells. The limiting factor for a single celled monster would be diffusion. The oxygen it needed to survive would have to diffuse all the way from the outside to the inside and it is just too far without help. that's why we have lungs and blood networks - to move oxygen around our bodies. A huge amoeba wouldn't have this. If it ate humans then it would have to catch them first. An amoeba moves very slowly and I think the 'pretend to be a pond' routine would work better. Amoebas eat things by invaginating the prey inside so a giant amoba would have to contain the whole human. The digestive juices would also have to be very strong. Killer plants question Hmm, intelligent plants. Well, some plants are able to signal to each other chemically if they are being eaten so they can communicate. There are carnivorous plants but the biggest thing they eat is frogs. Some plants can move their leaves and stems really quickly e.g. Venus Fly Trap, The Sensitive Plant etc. But I don't know of any which can move their roots quickly. perhaps if the plant could throw out poison pods if distubed (The way that Indian Balsam throws out seeds when disturbed)and the poison was so strong that the person died right away (so they didn't run out of the plants reach) the plant could get the nutrients as the body decayed and juices leached into the soil or if the plant had moving bits with digestive tips e.g. the sundew. I think that some work has been done on sensation in plants and they discovered that if a person burns a plant leaf and that person comes back again the plant 'recognizes' them in some way. I think they measured electrical activity in the plant. If they plant can detect chemicals it can smell. Plants don't have ears so they couldn't hear. Plants can detect light so with a bit of evolution they could probably get eyes. A carnivorous plant would probably live in a boggy area since they tend to be carnivorous in places where nutrients are scarce - good scenery for a B movie. A bit of evolution and I think you probably could get killer plants. Planty human - well, plant cells have hard cell walls and that is what makes them rigid so a human made of plant cells wouldn't be able to move much. A plant-like human though, I suppose if cells could photosynthesise then that would be an evolutionary benefit. Green people - yeah, why not? Radiation time - Ok, This is called the hopeful monster hypothesis. Anything which got a big blast of radiation would either die very rapidly from radiation poisening or die more slowly from cancer or infections (it would wipe out their immune system). If a person got a smaller blast then it may mutate their sex cells (eggs or sperm) and if the DNA was damaged then this would be passed onto the child. Most DNA damage is bad but you may occassionally get a good change. There's a king of heirachy of genes so if a gene high in the hierachy, a developmental control gene, got mutated this could have lots of downstream effects on the body. The problem is that if a new creature was producted what would want to mate with it? A leech couldn't grow big enough because it couldn't get the chemicals to diffuse into its great big body in the same way it could when smaller. Evolution takes millions of years so adding a bit of radiation wouldn't really speed things up much. Frozen creature question. Ok here's the problem with being frozen 1 - if you can't repair things in your body it would degrade. The ice crystals poke through the cell walls so when you melt you die. Some siberian frogs or toads get round this problem by having increasing the glucose level in their blood to very high levels which stops the crystals spoiling the cells. Some insects can survive being frozen and some fish which live very low in the water have "antifreeze solution" in their blood. The problem with a big beast being frozen over millions of years is that the earth around it would change. Earth would turn to stone, water might melt and dry up. You see the problem. Even ice moves so the thing could get torn to bits or ground away. Some little creatures called erm sea monkeys can lay eggs which survive a very long time and are activated by water. They also have some sort of predator which does the same. Insect/person idea. We do share some body organisation genes with insects but insects have very different chemical and physical composition to humans. They have their skeleton on the outside - we have ours on the inside, etc. You could probably put some insect genes into a human and make a new chemical in the body but genes need the right environment to be activated and functional. Big insects The problem insects have is that they cannot get big because they don't have an effective circulatory system. Their internal juices just sort of slosh about inside. Now, say they had long for natural selection to select features which eventually led to a circulatory system - they'de be able to get bigger. They would need an internal skeleton because they aren't designed to be big. Spiders legs work by hydraulics etc. Who knows - with time... They used to be bigger in the time of dinosaurs because the atmosphere was different. They would also need to get a way to heat up quickly as they are cold blooded and would be too slow to mave around if big. Ok. must get on with my work. Contact me firstname.lastname@example.org if you want more info becuase thinking about this was great fun.
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