Answer:
Explanation: Amphibian axis formation is an example of regulative development. The most important clue came from the fate map of this area of the egg, for it. Therefore, the specification of the dorsal-ventral axis begins at the moment of sperm entry. The Siamois protein is critical for the expression of organizer-specific genes
Natural selection eliminates aniamals that might be nessisary to life but it would hepl other animals survive as food for them
Answer:
Cell organelles are small structures that exist within cells and perform specialized functions
Based upon the presence and absence of membrane cell organelles can be classified into three types:
- Membrane less: Cell organelle that lack membrane for example ribosomes they are not bounded by any membrane.
- Single membraned: Cell organelle that are bounded by single membrane but they are only found in Eukaryotic cell. For example lysosome, Endoplasmic reticulum, lysosome, vacuole.
- Double membraned: Cell organelle that are bounded by double membrane. Example chloroplast and mitochondria, they are only present in eukaryotic cell.
Serotonin reuptake inhibitors, they are antidepressants.