A blastula is

a. a digestive organ.

b. the innermost germ layer.

c. a layer of embryological tissue.

d. a hollow ball of cells in an embryo.

A typical human cell contains 46 chromosomes. after mitosis and cytokinesis, each of the two new cells formed from the original cell

What is a direct cause of coral bleaching?

Choose the correct order: kingdom.

Why do males have some of the female sex hormones? Why do females have some of the males sex hormones

Which of these locations on earth experiences at least change in the number of daylight hours throughout the year? a. North pole b. terrestrial equator c. tropic of Capricorn d. tropic of Cancer e) South pole

A scientist has been working for 15 years to develop a new type of plastic material, but she has not yet been successful. Which of the following best explains why her work is still a success?

Technology can have good and bad effects. What is a bad effect of spraying pesticides on crops

Can your body make antibodies for pathogens that you have never been in contact with

What allows an organism to better survive in its envirmoment

The ozone hole is largely a consequence of the use of