They give it structure mostly. They also surround the organelles.
The right option is; a. A tree grows tall
A tree grows tall is an example of cell division at work because growth is associated with cell division. Also, cell division in multicellular organisms such as plant involves tissue growth and maintenance. Cell division is a process of reproduction in which a cell divides into two or more cells. In this process, production of new cells involves DNA replication and there are various types of cell division. Prokaryotes (such as bacteria) divide their cell using binary fission, while eukaryotes divide their cell by mitosis or meiosis in some.
Answer:
1. Weaker
2. Continuous
Explanation:
A tumor suppressor gene codes for retinoblastoma protein (pRb). The retinoblastoma protein binds to transcription factor E2F when DNA damage is detected. The E2F bound to pRb can not stimulate expression of genes that code for proteins required during the process of DNA synthesis. The cell can not enter the S phase.
On the other hand, when the retinoblastoma protein is phosphorylated by cyclin E-CDK2, E2F transcription factor is free to stimulate the expression of genes required for DNA synthesis and the cell proceeds from G1 to S phase.
When the mutated retinoblastoma gene code for a protein that serves as phosphorylated protein, it will not be able to bind strongly with E2F and there would be continuous expression of genes required for S phase.
