5. How do sharp spines on a cactus help it survive?
A. They make seeds for new plants,
B. They provide support for the plant.
C. They keep animals away from the plant.
D. They carry food to the flower.

What does it mean for a cell membrane to be selectively permable

How many chromosomes does each human cell contain? a. 23 chromosomes b. 26 chromosomes c. 43 chromosomes d. 46 chromosomes

Match the following items 1. rr 2. rr 3. identical alleles 4. unlike alleles 5. rr ()homozygous, recessive ()homozygous definition ()heterozygous, dominant cell ()heterozygous definition () homozygous, dominant cell