What are the two main forms of energy that power living systems

Which of these is a major trend in land plant evolution? a) the trend toward smaller size b) the trend toward a gametophyte-dominated life cycle c) the trend toward a sporophyte-dominated life cycle d) the trend toward larger gametophytes

Which of the following is one way in which organisms such as clown fish and sea turtles are able to overcome the many dangers that their offspring encounter and ensure that their species population numbers stay relatively steady

What is expressed when both alleles for a gene are equally expressed as in human blood type?