Tag: organization of life

Cell wall is found in bacteria (prokaryotes), fungi, algae and plants (eukaryotes). Bacterial cell walls are made up of peptidoglycan (murein). Algal cell walls are made up of gylcoproteins and polysaccharides. The cell walls of fungi are composed of chitin. Plant cell walls consists of a variety of polysaccharides, lipids, proteins etc. Prokaryotes lack nuclear membrane, and membrane bound subcellular organelles. Genetic material is naked and is called nucleoid.

So, the correct answer is 'Cell wall'.

Eukaryotic cells have a 'eu' or advanced nucleus having a well developed nuclear membrane, nucleolus and histone proteins for packaging of chromatin material. Eukaryotic cell also possesses several membrane bound organelles like plastids and mitochondria.

Presence of a cellulosic cell wall is a characteristic feature of plant cell. The cell wall present in a plant cell is dead at maturity. Animal cells lack cellulosic cell wall. Plant cells have chlorophyll present inside cell organelles called plastids. Chlorophyll captures light energy which is used by plants in photosynthesis. Thus, plants are autotrophic. An animal cell lacks chlorophyll. Hence, animals are heterotrophic.

Transcription is the process of formation of RNA from DNA. Transcription takes place inside the nucleus, where the DNA of a cell is stored. Since eukaryotes have a defined membrane bound nucleus, therefore transcription always takes place inside the nucleus in eukaryotic cells.
Translation, on the other hand is the process of production of proteins from messenger RNA. Production of proteins require ribosomes and ribosomes are found in cytoplasm. Thus, translation always occurs inside cytoplasm, whether it is a prokaryotic or eukaryotic cell.
In prokaryotes, however there is no define membrane bound nucleus. The DNA or the genetic material of prokaryotes lie inside cytoplasm only. Therefore, prokaryotic cells are the only cells where transcription and translation both occurs inside cytoplasm.
Hence, the correct option 'Prokaryotic cell'.

The basic difference between eukaryotes and prokaryotes is the presence and absence of a nuclear membrane. The eukaryotic cells are considered true cells because they possess a nuclear membrane and prokaryotes are considered false cells as they lack it.

So, the correct answer is 'Prokaryotic cells do not have a membrane-bounded nucleus, but eukaryotic cells do have such nucleus'.

Eukaryotes are organisms whose cells have a nucleus enclosed within membranes. A prokaryote is a unicellular organism that lacks a membrane-bound nucleus, mitochondria, or any other membrane-bound organelle.

• Golgi apparatus is not present in Prokaryotes, because prokaryotic cells lack a nucleus and membrane-bound structures such as mitochondria, lysosomes, Golgi apparatus. while eukaryotic cells have a nucleus and membrane-bound structures.

Prokaryotes do not possess membrane-bound organelles and well-defined nucleus. Nucleoid is a region in a prokaryotic cell, where most of the genetic material resides. It is not a well-defined membrane-bound region. 
Eukaryotes possess a well-defined nucleus and membrane-bound organelles as mitochondria, Golgi complex, etc. Nucleus is bound with double membrane in eukaryotic cells in which most of the genetic material is present. 

Eukaryotic chromosomes are made of chromatin, a nucleoprotein - DNA coiled around histone proteins while prokaryotic chromosomes are circular chromosome attached to the inside of the cell membrane. They are single chromosome plus plasmids