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Biology
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Outline photoactivation of photosystem II in the light-dependent reaction of photosynthesis.

light absorbed by pigment molecules (chlorophyll)causes electron to be raised to higher energy level; electron is passed along chain of carrier molecules in photosystem II

UP
Answered by Urte P. Biology tutor
6713 Views

How are epigenetics involved in regulating gene expression?

Epigenetic control of gene expression involves mechanisms that do not alter the sequence of DNA itself. External factors acting upon cells translate their signals via cascades to the nucleus, where they ...

HH
Answered by Harry H. Biology tutor
3138 Views

What's the difference between the 'lock and key' and 'induced fit' models for enzymes?

The lock and key hypothesis suggests that the enzyme has a fixed shape/structure and the substrate has to fit into this exactly for catalysis to occur. The induced fit hypothesis is different in that it s...

HW
Answered by Harriet W. Biology tutor
10529 Views

What steps occur during glycolysis?

Glycolysis is a metabolic process that takes place in the cytoplasm of a cell and occurs in both aerobic and anaerobic respiration pathways. One six-carbon compound is converted into two three-day on mol...

IS
Answered by Isabelle S. Biology tutor
11308 Views

What is a pathogen?

A microorganism that causes disease

ES
Answered by Emma S. Biology tutor
3034 Views

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