Mallard ducks secrete preen oil from a gland above their tail feathers. Mallards use their beaks to collect preen oil and work it into their feathers. This gives their feathers a waterproof quality and prevents water from collecting and soaking into their feathers. To which group of organic molecules do oils belong?

nucleic acid

lipid

protein

carbohydrate

After fertilization, which type of cellular division is responsible for the growth and development of a complex, multicellular organism?

In tomato plants, mendel found that the allele for smooth seeds (s) is dominant, while the allele for wrinkled seeds (s) is recessive. which of these punnett squares shows crosses between two plants heterozygous for smooth seeds? i need this to be answered as soon as ! sry the picture is bad quality

Two students are working together on an experiment that measures the effect of different liquid fertilizers on the thickness of plants’ stems. which is most likely to result in the greatest amount of error in their scientific experiment? a. one student measures the plant stem widths by using calipers. the other student measures the widths of the same plant stems again by using a different pair of calipers. b. one student measures the plant stem widths by using calipers. the other student types the measurements as they are taken into a computer spreadsheet. c. one student weighs liquids for the experiment by using a calibrated scale. the other student weighs liquids for the experiment by using a different calibrated scale.