25. the earth gets most of its energy from the sun. we call this energy solar energy. solar energy travels from the sun to the earth in rays. when the rays reach the earth, some bounce off clouds back into space—the rays are reflected. the earth absorbs most of the solar energy and turns it into heat. this heat warms the earth and the air around it. the sun is considered the ultimate source of energy for life on earth because a all organisms carry out photosynthesis. b the sun heats the earth’s atmosphere. c all organisms carry out cellular respiration. d photosynthetic organisms provide energy for other organisms on earth.

1. the passing of is the basis of heredity. 2. our encode the instructions that define our traits. 3. each of us has thousands of genes, which are made of and reside in our chromosomes. 4. in addition to our genes, the we live in also define our traits. 5. humans have two complete sets of chromosomes. 6. when parents conceive a child, each parent contributes set of chromosomes. 7. every child receives of its chromosomes from the mother and half from the father. 8. this transfer takes place at when the father’s sperm joins the mother’s egg. 9. while most cells in our bodies have two sets of chromosomes, or a total of egg and sperm each have chromosomes. 10. when egg and sperm unite they create a single cell called a 11. each parent contributes complete set of chromosomes to their child. 12. since the parents contribute the chromosomes to each new child, every child inherits a unique set of chromosomes. 13. as a result, every baby will have a combination of traits.

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere, b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify, d)anaerobic bacteria kept thriving with more oxygen

Which best example best demonstrates the importance of having knowledge of evolutionary relationships? a. illustration of a plant b. organ transplantation between species c. blood donation from a human d. do you need sequence of an insect.