The first step in digestion starts with
tongue
esophagus
saliva

Compare the shapes of the bones of the human skull with the shapes of the bones of the human leg. how do the shapes differ? why are the shapes important?

Molecules like glucose and amino acids are not lipid soluble, so cannot cross the cell membrane by simple diffusion. instead, they are shuttled across by carrier proteins in the membrane from high to low concentration. does this process require energy from the cell? this is an example of what type of molecular movement?

Suppose a point mutation, such as a change from an adenine to a guanine, occurs in the genome of a human sperm cell. the mutation could occur in any region of a gene. the effect of the mutation on the phenotype of the offspring will be determined by where the mutation occurs and its effect on the final gene product. in which of the following scenarios could the mutation alter the phenotype of the offspring? select all of the scenarios that apply the mutation occurs in the promoter and affects the rate of gene transcription. the mutation results in a new, dominant allele the mutation occurs in a portion of an intron not responsible for exon splicing the mutation occurs in a gene that controls development and alters differentiation of a cell type during development. the mutation occurs in a codon and alters the function of the final protein e mutation occurs in a codon, and the amino acid sequence of the final protein is unchanged.