Carol and joseph have freckles and curly red hair. all of their children, except one, also have freckles and curly red hair. their son, sam, has the same curly red hair but not one freckle! how can a child get a chromosome that is totally different from the original chromosomes of both parents? a) gene flow b) genetic drift c) crossing over d) natural selection

Describe the primary and secondary immune response in terms of speed and number of antibodies produced?

Molecular models of two different substances are shown below. in the molecule on the left, the oxygen atom pulls on electrons more strongly than the hydrogen atoms. in the molecule on the right, the two oxygen atoms pull on the shared electrons with the same strength. water molecule, h, o oxygen molecule, oz when the two substances are put in the same container, they do not attract each other. why does this happen? a. they both contain oxygen. b. one is polar and one is nonpolar. c . they are both polar. d. they contain different elements.

As the pea seeds respire, the level of coloured liquid in the left hand part of the capillary tube rises. by referring to what is happening in the apparatus, explain why the level of liquid changes