Some investigators concluded that the first organisms consisted of rna rather than dna. what is importance of this "rna world" period?

Sharks have internal fertilization. true or false.

Is cooking an egg endothermic or exothermic chemical reaction?

Why is it important that the phospholipid bilayer be both hydrophobic and hydrophilic?

Why aren't enzymes just proteins?

Which of the following involves only biotic factors? A. a pine tree absorbing light from the Sun B. a spider building a web in the corner of a building C. a duck catching and eating a snail D. an otter using a stone to break open a sea urchin

One of the first breakthroughs in biotechnology was the discovery of the gene that makes insulin. Part of this process involved scientists making DNA to match each possible sequence of insulin mRNA. What was the next step of this process? A.

If mollusks evolved before arthropods, where will their fossils be found?

Over time, a river cut through a field where some mice lived and some birds were nesting. Tell over time why the mice developed into 2 different species, but the birds did not

Using radioactively labeled dna probes in studies of heredity makes it possible for a scientist to

During the first four days after conception, the zygote undergoes rapid cell divisions and becomes multicellular. What is this cell division called?