What happens when a sodium atom and a chlorine atom exchange an electron? a. they form an oxygen molecule. b. they form an ionic bond. c. they form a covalent bond. d. they form a water molecule.

Describe your dna model. which part do the straws represent? the pushpins? the paper clips and the black dots you made with the marker?

Crossing over is a method of (blank)?

Easy 6th grade work! 100 points! i need fast! compare the parts of a cell and the cell as a whole to another common nonliving system (i. e., a car, a city, describe the parts of a cell and their primary function.