Wich structure produces chemicals that regulate the reproductive cycle?

What factor (s) might prevent the skin from keeping pathogens out of your body?

What observations did you make regarding the lymphatic system of the fetal pig?

What do chordates have that makes them different? A. no body cavities B. a notochord C. under-developed organ systems

Which of these is a common passage for both the digestive and respiratory systems?

If a Killer whale is feeding at the fourth trophic level, how much phytoplankton mass is required to add each gram of new mass to the whale? Assume that 10% of the energy at one trophic level is transferred to the next level.

What is an abiotic factor of a marine ecosystem? A). Food produced B). Temperature change as you go deeper into the ocean C). Reproduction of animals

1. Suppose that xylem were located only in the roots and stems of a plant. Would fluids in the xylem still move? Explain.

What activity will decrease body temperature? Sweating Exercising Adding clothing Shivering

Organisms with true radial symmetry A. tend to be highly mobile. B. do not have a distinct head region and tend to be sedentary or passive drifters. C. can be divided into two matching halves along only one plane. D.

1. The Earth's carbon cycle consists of the flow, cycling, and recycling of all of the carbon on the Earth. Every living organism's composition includes the element carbon. How does carbon become part of living organisms?