bio questions!

[jvss123]

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Can some one please briefly explain the following two concepts?

1) what are the exact ingredients of the "primordial soup"?

2) I understand the general concept of endosymbiotic hypothesis, but cant fully grasp how mitochondria descended from free-living prokaryotic heterotrophs, while chloroplasts descended from free-living prokaryotic autotrophs. Please explain.

Thanks a million 🙂

 

[dentalWorks]

Can some one please briefly explain the following two concepts?

1) what are the exact ingredients of the "primordial soup"?

2) I understand the general concept of endosymbiotic hypothesis, but cant fully grasp how mitochondria descended from free-living prokaryotic heterotrophs, while chloroplasts descended from free-living prokaryotic autotrophs. Please explain.

Thanks a million 🙂

for 1)
Primordial soup is the idea that if you can mix up some crucial non organic compounds in an environment, and apply the right conditions into that environment, you will be able to see precursors of living molecules forming up (example if you stick CO2, some NH3, some sulfur, phosphase, hydrogen, and a few others non-organic compounds ALL together, and give them heat (sun light) and right atmospheric presures).... They will (for example) begin to form some basic amino acids. I forgot the name of the, but he did this experiement back in the 1950s, and this was exactly what happen.

The "soup" are the non-organic compounds

for 2)
Im sure you know this already, but the FIRST living cells in our world were prokaryotes (you aggree with me right? good), wer talking about 3-4 billion years ago.
Now as prokaryotes grew, they developed into different types (example some developed into heterotrophs and some into phototrohps)....... meanwhile, evolution was taking place and transforming some of the prokaryotes into eukaryotes.

One of the things that eukaryotes did was they "ate" (englufed) the prehistoric heterotophs or phototrophs (in today's items, those engulfed cells became known as mitochondria or chloroplast)

 

[dentalpath]

"I understand the general concept of endosymbiotic hypothesis, but cant fully grasp how mitochondria descended from free-living prokaryotic heterotrophs, while chloroplasts descended from free-living prokaryotic autotrophs. Please explain"

I suppose you already have the answer to your first question in the post above, as for why mitochondria descended from free living heterotrophs and chloroplast fom free living autotrophs..it is because as you already know cholorplasts contain P680 and P700, both of which are required to perform photosynthesis and generate organic molcules using sunlight (autotrophic). However mitochondria can only generate energy from existing organic molecules, remember glycolysis in the cytoplasm starts with breakdown of glucose into pyruvate which combines with Coenzyme A to give Acetyl Co A (Krebs cycle. Finally oxidative phosphorylation generates ATP from the electron transport chain. So mitochondria probably had to "eat" or engulf other bacteria or molecules (heterotrophs) to gain organic molecules..like glucose.

 

[jvss123]

that is what i thought right, but i dont know why every endosymbiotic hypo question i encounter, i seem to get it wrong... i guess i just have to read the question carefully ... thanx a lot =)