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Degree: Biological Sciences (Bachelors) - Durham University
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Mitosis can be grouped into four main stages: prophase, metaphase, anaphase and telophase.
Prophase: the chromosomes supercondense, the nuclear envelope disintegrates and the centrioles migrate to the poles of the cell.
Metaphase: the chromosomes line up at the equator of the cell, moved by spindle fibres (which are attached to the centromeres) from the centrioles.
Anaphase: the chromosomes are split at the centromeres and one half of each is pulled one pole, and the other to the other.
Telophase: the cell membrane constricts around the middle of the cell and the nuclear envelopes begin to appear around the chromosomes. Eventually the cell splits in two, forming two identical daughter cells with n genetic material.see more
These two sets of reactions are very different yet equally important in the process of photosynthesis.
The light dependent reactions consist of chlorophyll molecules absorbing a photon (hence light dependent) that causes electrons in the molecule to be raised to a higher energy level and pass down the electron transport chain, which makes energy available to produce ATP. The loss of electrons causes the splitting of water (known as photolysis) into 2H+, 1/2 O2 and electrons, which replace those lost by the chlorophyll. The electrons that flowed through the electron transport chain combine with the hydrogen ions from water and NADP to form NADPH + H+. These reactions occur on the thylakoid membranes.
The light independent reactions consist of the Calvin cycle where CO2 is fixed by combining with RuBP to form 2GP, and then uses the products of the light dependent reactions to form GALP, which can be converted into many different products.see more