Tag: membranous and non-membranous organells

Nuclear membrane is a double layered membrane, made up of lipid bilayer and proteins that separates the nucleus from the rest of the cell. The cytoplasm contains the most of the hydrolytic enzymes, which can affect the genetic material. The membrane protects the genetic material from different chemical reactions. It decides what to enter and exit from the nucleus by acting selectively permeable. It also provides structural support to the nucleus.

Nuclear pores  are the passage through which movement of RNA and protein molecules takes place between nucleus and cytoplasm.

• The living matter of cell is protoplasm which is the colorless material composed of a mixture of small molecules such as ions, amino acid etc.

• The nucleus of a cell is separated from the cytoplasm by a double membrane known as the nuclear envelope.
  
• Prokaryotes do not have genomic DNA that is concentrated and localized to a small area within the cell called nucleoid region, thus it is absent in them.

• Whereas, a eukaryotic cell contains all the organelles and nucleus which is separated from the cytoplasm by the nuclear envelope.
• The correct answer is OPTION C.

The thread like structure present in the nucleus are called the chromosomes or the chromatin, when the degree of condensation is very less.

• RNA is found everywhere- nucleus, nucleolus, mitochondria, chloroplasts, ribosomes, cytoplasm, etc. RNAs are 3 different types- mRNA, tRNA and rRNA. mRNA and tRNA are found in the cytoplasm and rRNA in the nucleus.
• The ribosomes can be free within the cytoplasm of a cell or attached to the endoplasmic reticulum but do not present inside the nucleus. RNA and ribosomes act together resulting in the synthesis of proteins.

• The cell is the basic structural, functional, and biological unit of all known living organisms. A cell is the smallest unit of life. 
• Cells are often called the "building blocks of life". 
•  Cells are of two types: eukaryotic, which contain a nucleus, and prokaryotic, which do not. 
• Prokaryotes are single-celled organisms, while eukaryotes can be either single-celled or multicellular. 
• Hence, the cell of all living organisms have a nucleus is correct.
• So, the correct answer is 'cell of all living organisms has a nucleus'.

Within the nucleus is a small subspace known as the nucleolus. It is not bound by a membrane, so it is not an organelle. This space forms near the part of DNA with instructions for making ribosomes, the molecules responsible for making proteins.