The Lock-and-key mechanism was first proposed by Emil Fischer which described as the enzymatic reactions whereby an enzyme with a single substrate binds temporarily to form a substrate complex.
The lock-and-key mechanism is usually associated with the complementary shapes of an enzyme with a single substrate, wherein the lock that is being referred to is the enzyme and the substrate is the key. One right sized substrate (key) fits into the active site (key hole) of the enzyme (lock).
The active site which is mentioned above is structurally complementary to the substrate. This is the temporary binding site on the enzymes. Just like a lock and key, the enzyme as the lock and the substrate as the key is said to fit together.
I think the hydra lacks the specialized cells for touch and chemical detection. On the other hand earthworms have touch, light, vibration and chemical receptors along the entire body surface. Both of them are invertebrates (those animals without a backbone), they include insects, worms, jelly fish, spiders among other animals.
Increasing cloud cover, since it’ll block off any sunlight
Answer: water will move out of the animal cell causing it to swell and burst (Option C)
Explanation:
When a cell is immersed into a salty solution, the osmotic pressure generated by concentration differences of salt, will make the salt come in due to cell self-protection mechanism of the cell and water will come out, eventually the cell can burst .But since the animal cells has a higher concentration of salt and the solution has a lower concentration osmosis will take place and salt will move from higher salt concentration to lower.
