Which of these statements is true about tracheids? 1-They lose their end walls at maturity.

2-They open at each end with bar-like strips across the opening.

3-They are cells with pitted ends.

4-They have sieve plates.

During the process of meiosis, special cells called gametes are formed. gametes only have half the number of chromosomes that the other cells in the body have. what form of reproduction do organisms that produce gametes use?

Astudent wants to test the hypothesis that fertilizer improves the growth rate of grass seeds. to test this hypothesis, the student put the same amount of grass seed in 3 containers with the same type of soil. the student measured the growth at the end of the week. all plants received equal amounts of water and sunlight. if you were asked to graph this data, what would you place on the x-axis? a. fertilizer b. water c. plant growth d. week one

What are the characteristics of subsystem