Which of these is the foundation for relative dating a. earth is very old b. deeper rock strata are older c. radioisotopes decay at a constant rate d. organism can be closely related to each other.

Organelles found in plant cells that function through photosynthesis to produce glucose from carbon dioxide and water are called — question 21 options: chloroplasts guard cells photosynthons

During crossing-over, a. genetic material is exchanged between nonsister chromatids, resulting in new combinations of alleles. b. nonsister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. c. one homologous chromosome of a tetrad is exchanged with another tetrad, resulting in new combinations of alleles. d. sister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. e. genetic material is exchanged between sister chromatids, resulting in new combinations of alleles.

Polar zones are cold and tend to be dry because of a pressure system of cold. low high