Which of these is true of echinoderms
a. they have heads.
b. they have radial symmetry.
c. they have shells.
d. they have smooth skin.

Consider darwin's first writings on the theory of natural selection. an important point of darwin's essay on the principle of population, written in 1798, was a peer's observation that in nature plants and animals produce far more offspring than can survive, this observation can be attributed to a) charles lyell. b) thomas malthus. c) jean-baptiste lamarck. d) johann friedrich meckel.

What is a limitation of using a chemical formula, such as c6h1206, to represent a compound? the chemical formula does not show the types of elements that make up the compound. the chemical formula does not show how the atoms are connected to one another the chemical formula does not show the number of atoms of each element in a molecule. the chemical formula does not show the chemical symbols of the elements in the compound

Anormal appearing couple is found to be heterozygous recessive for albinism both have the genotype aa the gene responsible for albinism is recessive to the normal pigment-producing gene what are the changes of their children being albino