Mutations that improve an individual's ability to survive and reproduce are

2points what is the term for a female reproductive cell? a. egg b. chromatid c. allele d. fertilization

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2

The cretaceous period spanned the time interval between and 65 million years ago. 250 million 144 million 75 million 200 million