Frogs reproduce sexually. why do frogs require water to reproduce?

how the blood, the nervous system, the cardiovascular system, and the muscular system each contribute to and support human respiration.

Color of chickens is determined by interacting loci: aa or aa give white, aabb or aabb give colored, and aabb produces white. what are the phenotypic frequencies of the offspring from a cross between two fully heterozygous chickens

The outcome of the gram stain is based on differences in the cell's

Which hormone is stimulated by rising blood levels of K+, low blood levels of Na + and decreasing blood volume and blood pressure?

Which of the following is a cause of urbanization? a. living in cities became more expensive than living in rural areas. b. agricultural production became more efficient. c. suburban homes became larger than urban homes. d.

Future directions and careers in ethnobiology

Joy and shawn have a good marriage, but they disagree about food. they buy two different loaves of bread each week, one white and one wheat, so that they each have the bread they like best.

Which of the above mammals are the most closely related to each other? A. the dolphin and the whale B. the manatee and the sea lion C. the dolphin and the manatee D. the manatee and the whale

Which of the following is a fungus that has a symbiotic relationship with plant roots? mycorrhizae slime mold lichen wheat rust

Explain how enzymes are sensitive to their environment