This is a easy one! a promoter<span> is a region of DNA that initiates transcription of a particular gene. </span>Promoters<span> are located near the transcription start sites of genes, on the same strand and upstream on the DNA</span>
Hi Geny!
Question - Describe the cell theory and the developments that led to the cell theory.
Answer:
There are 3 main components of cell theory:
- Each and every organism is wither unicellular or multicellular.
- The basic unit of life is the cell.
- Cells are created from cells that had existed previously.
There were 3 scientists that made cell theory each of the 3 components of above were the 3 scientists.
- Mathia Schleiden discovered that plants were made of mainly cells.
- Rudolf Virchow discovered that cells are created from calls that had existed previously.
- Theodore Schwann discovered that animals were also made of mainly cells.
Hope This Helps :)
The walls of xylem cells are lignified (strengthened with a substance called lignin ). This allows the xylem to withstand pressure changes as water moves through the plant.
The cell membrane is flexible because of the presence of oil like substances called phospholipids, which gives it a fluid nature. While as the cell walls are rigid because of the presence of the thick layers of the substances like cellulose in plants, chitin in fungi and peptidoglycon in bacteria.
<span>Australopithecus afarensis</span>