Emily's crops are dying; she noticed the ground has white spots on it and is cracked. What could be the cause?

a. Acid rain on soil
b. Salinization
c. Waterlogged soil
d. Desertification

Which of the following is a main difference in cell structure between an onion cell and a human cheek cell? a. an onion cell contains one nucleus, whereas a human cheek cell contains two nuclei. b. an onion cell has a cell wall. c. a human cheek cell contains chloroplasts. d. there is no difference between an onion cell and a human cheek cell. you for your.

The relationship between intron and exon

How do disease caused by bacteria and disease caused by viruses react to antibiotics?