Unlike animal cells, plant cells have cell walls that make them rigid. which organelle, other than the cell wall, also plays a vital role in providing rigidity to plant cells? a) nucleus b) chloroplast c) central vacuole d) endoplasmic reticulum

Which pattern most likely came from a gunshot and which one was produced from a blow on the head? explain your answer?

Astudent observes a star from two positions of earth in its orbit, in summer and winter, and measures the change in the position of the star. which of these can be best calculated by this method?

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.