Crossing-over can be found in stage of

Barbara is converting 78°f to degrees celsius. first, she subtracts 32 from 78. what is the next step?

How is the male reproductive system different from other body systems? it isn’t necessary to vital signs. it monitors other body systems, and adjusts if necessary. it transports items from one system to another. it is the only system that produces hormones in the male.

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?