If a DNA molecule is compared to a spiral staircase, what parts make up the steps?

sugar and nitrogen base

pairs of nitrogen bases

sugar and phosphate

pairs of sugars

Explain how the gene governs the making of cellulase molecules

Which phase of the Moon produces the least variation in tides on Earth?

Which of the following statements is true? All mutations cause evolution. Any change to the DNA of an organism is called evolution. All mutations are harmful. Evolution happens slowly over time.

Susan goes outside to measure the light intensity that different parts of her yard receive. She notes that part of her lawn receives sunlight at an intensity of 250 and other parts receive sunlight at an intensity of 450.

A rollercoaster car at the top of the hill, and a slope that sits above a dam are all examples of what kind of energy?

A mother sleeping in the middle of the night nevertheless responds when she hears her 2-year-old daughter crying in the adjacent bedroom. This indicates that the mother possesses:

How can farmers keep topsoil on their land? check all that apply. a. close their gates b. keep plants growing c. plant trees to shield fields from the wind d. do not plow when extremely heavy rains are expected?

Measures how much matter is present in a substance

How is artificial selection similar to natural selection?

Which of these is a distinguishing characteristic of terrestrial habitats? O A. Plant life O B. Presence of oxygen O C. Salinity levels O D. Human presence