Hello welcome to the final episode of the Mini Wiki series. For this one I thought I’d go back through the episodes on cell biology and give you my top 10 pieces of information.
10 – THE CENTRAL DOGMA
The central dogma is the process where we go from DNA to proteins. The three stages of the central dogma are replication, transcription and translation.
9 – DNA
The four nitrogen bases that make up DNA are Adenine (A), Thymine (T), Cytosine (C) and Guanine (G). The bases come in two types purines (A & G) and pyrimidines (T&G). The bases then pair up with 1 purine and 1 pyrimidine nucleotide. A & T pair together with 2 hydrogen bonds and C & G pair together with 3 hydrogen bonds. This then causes the double helix shape with the phosphate and sugar groups being on the outside (known as the sugar phosphate backbone) and the bases being on the inside.
8 – RNA
Firstly RNA is a linear molecule unlike the double helix of DNA. RNA does not contain the nitrogenous base Thymine, it is replaced with the base Uracil. Finally, RNA can be found outside the nucleus unlike with DNA.
7 – Animal Cell
Animals cells are essentially sacks of cytoplasm, they are bordered by a cell membrane and within the cytoplasm you have organelles. The cell membrane keeps everything that the cell wants in inside and everything else out. The organelles all have their own function to keep the cell going and the cytoplasm is where the majority of the cells chemical processes take place.
6 – Plant Cell
There are a number of different ways plant cells are different from animal cells. Firstly plant cells have a cell wall. This is outside of the cell membrane that provides protection and structure, it’s made of predominately cellulose. This leads on to another difference and that is shape, plant cells have a more rigid rectangular shape compared to animal cells, which tend to be more varied. Plant cells also contain one central large vacuole, animal cells have smaller vacuoles that are more doted around. The other main difference is plant cells contain chloroplasts which are essential for the process of photosynthesis.
5 – Organelles
Why are organelles called organelles? The world organelle is a diminutive from the Latin organum meaning“instrument,” in Medieval Latin this means “organ of the body”.
4 – More Organelles
The nucleus is like the central console of the cell. It’s a membrane bound structure that contains the cell’s hereditary (DNA) information and controls the cell’s growth and reproduction. Its the most prominent of all the organelles and can be seen using a normal microscope. (No fancy electron microscope to see these guys in action). The nucleus itself has quite a complex structure but that’s for another wiki.
3 – Cell Cycle
You can look at the cell cycle as having three distinct phases. Interphase, Mitosis and Cytokinesis. We will cover mitosis and cytokinesis next time for this mini wiki we’re focusing on the phases within interphase.
There are 5 stages to mitosis. They are prophase, prometaphase, metaphase, anaphase and telophase.
The definition of meiosis is a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.
I hope you have enjoyed this series and I definitely will be continuing to write about cell biology in upcoming blog posts!