1. At solar noon on an equinox date what would be the Sun's altitude if the latitude of NYC is 41 degrees north?

Suppose a scientist measures the amount of dna per cell of a particular diploid species at various stages of meiosis. she finds that the meiotic cells contain 3.7 pg , 7.3 pg , or 14.6 pg of dna. match each stage of the cell cycle to the corresponding amount of dna contained within a cell at that stage.

How is ribosomal rna useful as a molecular clock? a. a large portion of the dna ring is not vital to structure or function, allowing it to accumulate neutral mutations. b. its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. c. a slow mutation rate makes it useful for determining evolutionary relationships between ancient species. d. it is only found in select organisms, making it easier to compare relationships between species that have it.

2. which of the following statements does not accurately describe stem cells? a. embryonic stem cells make up the inner cell mass of a blastocyst. b. with more research, stem cells may be used to repair or replace damaged cells. c. the use of stem cells is without any objections since it can be used in therapies to humans. d. adult stem cells are multipotent and can differentiate into many types of cells.