Which of the following is true of a zygote?
A. lt forms into a blastocyst
C. It produces haploid male gametophytes
D. It is made up of only one cell
B. It is an unfertilized egg

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.

Your two friends just told you what to order for them at the drive through fast food restaurant. you give the order but when the food comes about 10 minutes later, you don't remember what each of your friends ordered your memory of the order was in __ memory. a. semantic b. flashbulb c. long-term d. short-term i think i know but i'm not really sure

The earth formed roughly 4.5 billion years ago, yet evidence of life dates back to about 3.5 billion years ago. which one is not a possible hypothesis of how life on earth arose?