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Biology Index. Atlas of Living Australia « sharing biodiversity knowledge. Difen Biology. Replication vs Transcription. Cell division is essential for an organism to grow, but when a cell divides it must replicate the DNA in its genome so that the two daughter cells have the same genetic information as their parent.

Replication vs Transcription

DNA provides a simple mechanism for replication. In transcription, or RNA synthesis, the codons of a gene are copied into messenger RNA by RNA polymerase. As opposed to DNA replication, transcription results in an RNA complement that includes uracil (U) in all instances where thymine (T) would have occurred in a DNA complement. Share this comparison: If you read this far, you should follow us:

DNA vs RNA. DNA, or deoxyribonucleic acid, is like a blueprint of biological guidelines that a living organism must follow to exist and remain functional.


RNA, or ribonucleic acid, helps carry out this blueprint's guidelines. Of the two, RNA is more versatile than DNA, capable of performing numerous, diverse tasks in an organism, but DNA is more stable and holds more complex information for longer periods of time. Structure DNA and RNA are nucleic acids. Nucleic acids are long biological macromolecules that consist of smaller molecules called nucleotides. Structural differences between DNA and RNA. DNA is found in the nucleus of a cell (nuclear DNA) and in mitochondria (mitochondrial DNA). During transcription, RNA, a single-stranded, linear molecule, is formed. RNA folding in on itself into a hairpin loop. In both molecules, the nucleobases are attached to their sugar-phosphate backbone. In RNA, adenine and uracil (not thymine) link together, while cytosine still links to guanine.

Function Recent News. Eukaryotic Cell vs Prokaryotic Cell. The distinction between prokaryotes and eukaryotes is considered to be the most important distinction among groups of organisms.

Eukaryotic Cell vs Prokaryotic Cell

Eukaryotic cells contain membrane-bound organelles, such as the nucleus, while prokaryotic cells do not. Plant Cell vs Animal Cell. Plant and animal cells have several differences and similarities.

Plant Cell vs Animal Cell

For example, animal cells do not have a cell wall or chloroplasts but plant cells do. Animal cells are round and irregular in shape while plant cells have fixed, rectangular shapes. Plant and animal cells are both eukaryotic cells, so they have several features in common, such as the presence of a cell membrane, and cell organelles, like the nucleus, mitochondria and endoplasmic reticulum. Chloroplasts Plants are autotrophs; they produce energy from sunlight through the process of photosynthesis, for which they use cell organelles called chloroplasts. Shape Another difference between plant cells and animal cells is that animal cells are round whereas plant cells are rectangular. Cell Wall Plant cells have a rigid cell wall that surrounds the cell membrane. Vacuoles Shape and size of vacuoles Animal cells have one or more small vacuoles whereas plant cells have one large central vacuole that can take up to 90% of cell volume.

Active and Passive Transport. Active and passive transport are biological processes that move oxygen, water and nutrients into cells and remove waste products.

Active and Passive Transport

Active transport requires chemical energy because it is the movement of biochemicals from areas of lower concentration to areas of higher concentration. On the other hand, passive trasport moves biochemicals from areas of high concentration to areas of low concentration; so it does not require energy. Process There are two types of active transport: primary and secondary.

In primary active transport, specialized trans-membrane proteins recognize the presence of a substance that needs to be transported and serve as pumps, powered by the chemical energy ATP, to carry the desired biochemicals across. Mitosis and Meiosis - Comparison Chart, Video and Pictures. Cells divide and reproduce in two ways: mitosis and meiosis.

Mitosis and Meiosis - Comparison Chart, Video and Pictures

Mitosis is a process of cell division that results in two genetically identical daughter cells developing from a single parent cell. Meiosis, on the other hand, is the division of a germ cell involving two fissions of the nucleus and giving rise to four gametes, or sex cells, each possessing half the number of chromosomes of the original cell. Mitosis is used by single-celled organisms to reproduce; it is also used for the organic growth of tissues, fibers, and membranes. Meiosis is found in sexual reproduction of organisms. The male and female sex cells (i.e., egg and sperm) are the end result of meiosis; they combine to create new, genetically different offspring.

Differences in Purpose. ARKive - Discover the world's most endangered species. Biology. Bioman Biology: The Fun Place to Learn Biology!