The correct answer is: 5) NER recognizes helix distortions, while BER recognizes specific base damage.
DNA damage that occurs as a result of radiation, oxidizing reagents, chemicals and other mutagens can be repaired. Excision repair repairs single strand DNA damage and it includes:
• Nucleotide excision repair (NER)-it detects and repairs types of damage that distort the DNA double helix such as those of UV radiation (thymine dimers); not only the damaged nucleotide(s) are removed but also a surrounding patch of DNA
• Base excision repair (BER)-it detects and removes certain types of damaged bases (small, non-helix-distorting bases); enzyme glycosylase is responsible for this type of repair
The top layers are the youngest and the farther you go down, the older they get. I’ll put it in exact order in a minute.
A biologist wants to know whether a plant's growth is affected by the material it's planted in. She plants lima bean seeds in a jar of dirt, a jar of cotton, and a jar of rocks, then provides each jar with equal amounts of water, plant food, and sunlight. In this experiment, the independent variable is the material in which the plant is getting planted.
The independent variables are the variable that are in control of the experimenter. The independent variables do not depend on the other variable for their selection. The changes in a dependent variable is studied by varying the independent variable accordingly.