Which of the following body structure and physiology of bird are not important for the flight of birds 1.feathery and light wings
2.four chambered heart
3. Use of gill as a breathing organ
4. hallow body to reduce weight

Dna replication or repair occurs in a cell in all of thw following situations except when

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.

An animal cell (left) and a plant cell (right) are shown.which organelle, labeled x in the diagram, is found in both plant and animal cells?