What accounts for genetic material from each of an organism's parents being present in sperm and egg cells? 1. Crossing over during meiosis

2. Regeneration of new cells

3. Cytokinesis of new cells

4. Crossing over during mitosis

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands

the most common type of reef is the fringing reef. this type of reef grows seaward directly from the shore. they form borders along the shoreline and surrounding islands.