In a pedigree showing a dominant disorder, what is the symbol of a family member who is unaffected?

During the day, plants produce by splitting water molecules in the light-dependent reactions of photosynthesis. at the same time, plants use cellular respiration to produce some of the needed by the light-independent reactions to make sugars. during the night, plants produce because takes place.

The big bang theory suggest that the universe is about - 300 million years old - 4.6 billion years old - 30 billion years old - 13 billion years old

In 1994, telomerase activity was discovered in human cancer cell lines. although telomerase activity is rarely present in human somatic tissue, this discovery indicated that humans do contain the genes for telomerase proteins and telomerase rna. since inappropriate activation of telomerase may contribute to cancer, why do you think the genes coding for this enzyme have been maintained in the human genome throughout evolution?