No, different organisms have a different number of chromosomes
Monocots
1. Embryo has single cotyledon
2. Flower parts in multiples of threes
3.Major leaf veins are parallel.
4. Roots are adventitious
5. Stem vascular bundles scattered
6. Pollen with single furrow or pore.
7. Secondary growth absent.
Dicots
1. Embryo with two cotyledon
2. Flower parts are in multiples of four or five.
3. Major leaf veins reticulated.
4. Roots develop from radicle.
5. Stem vascular bundles are in a ring.
6. Pollen with three furrows or pores.
7. Secondary growth often present.
Well first it grows then it divides into2 identical cells reproducing itself
Answer:
Oncogenes result from a mutation in proto-oncogenes.
Explanation:
- Protooncogenes control the growth and division of cells.
- The proteins encoded by proto-oncogenes include growth factors, growth factor receptors, transcription factors and signal transducers.
- They contribute to the transformation process by driving cell proliferation or reducing sensitivity to cell death.
- Several types of genetic and epigenetic changes convert these proto-oncogenes to oncogenes.
- Oncogenes arise due to the changes that increases the expression of proto-oncogenes .
- Oncogenes are one of the causes of cancers.
A proto-oncogenes can turn into oncogene by following ways:
- A point mutation such as deletion, insertion and substitution in the proto-oncogene can lead to formation of oncogenes.
- Chromosomal translocation may result in activation of proto-oncogene as seen in Burkitt's lymphoma.
- Insertion of a mobile genetic material such as retrovirus changes the gene expression, but leaves their coding sequence intact.
- Activation of proto-oncogene can also occur from reduplication and amplification of DNA sequence.
Answer:
D. The cells in group B are prokaryotic because they replicate their DNA in the cytoplasm.
Explanation:
The cells of group A are prokaryotic because it is prokaryotes which do not have a double membranous structure called nucleus for storing their genetic material. The genetic material of prokaryotes is spread in the cytoplasm in the form of a circular DNA which is called as nucleoid. Since they do not have a separate organelle like nucleus for storage of their genetic material, they are bound to replicate their DNA in the cytoplasm. In contrast to prokaryotes, eukaryotes have nucleus for storage of their genetic material and in eukaryotes replication is an exclusively nuclear event.
