Who rediscovered Aristarchus's model of a heliocentric solar system? Copernicus Galileo Kepler Ptolemy

Which organisms have pharyngeal arches that develop from all three germ layers and go through the same development stages as embryos? 1.bird 2.ladybug 3.starfish 4.snake

Which statement best describes the relationship between an allele and a gene? question 1 a. an allele is a variation of a gene that can be expressed as a phenotype. b. an allele is the part of a gene that attaches to messenger rna molecules. c. an allele is a segment of a dna molecule that controls replication of a gene.

Match the correct terms to their descriptions a system in which only energy but not matter is exchanged frozen water in snow part of geosphere that includes only soil a thin layer between the troposphere and the stratosphere cryosphere tropopause closed system pedosphere