Battery operated device was invented to control the speed in rhythm of the human heart which professional was mainly involved in this invention

How do accessory pigments chlorophyll?

Hey me with this one❤☺❤ how do you say that a cell also has a life span and death like an organism? give one example.

Astudent reads the following text in a science book: scientific evidence tells us that the cause of earths four seasons is the tilt of earth as it revolves around the sound the student is instructed to illustrate this information in a science book. how will the student illustrate winter in the northern hemisphere? a. earths northern hemisphere will tilt away from the sun. b. earths northern hemisphere will tilt toward the sun. c. earths orbit will be farther away than from the sun d. earths southern hemisphere will tilt away from the sun.