Melatonin is secreted by

A. the hypothalamus during the day

B. the pineal gland during the night

C. the autonomic nervous system during the winter

D. the thyroid gland during cold seasons

What is true of intercellular signals that do not go through direct connections between cells, such as plasmodesmata?

Which mutation would be most beneficial to a panther and its descendents? A. an extra toe B. thicker fur C. eye color changed from green to brown D. slightly larger ears

In science class, Maria observes a white-colored cut flower. She sees that the petals turn red when the flower is sitting in a vase that has red-colored water. She forms a hypothesis that the color reaches the flower through the stem.

An entity cluster is formed by combing multiple interrelated entities into ___.

Which type of DNA would you prefer in a investigation: mitochondrional dna or nuclear dna? why?

Match the staining techniques with their purpose. A Negative stain such as India ink or Congo red. B The Gram stain C The Ziehl-Neelsen Acid-fast stain D Simple stain with a basic dye E The Schaeffer-Fulton Endospore stain Stain microbes a bright

Sandy puts a paper clip on the table and puts a magnet near the paper clip. The paper clip begins to move. What type of forces are acting on the paper clip?

Which statement is an example of absolute age? 1) Dinosaurs lived a long time ago 2) Trilobites lives before dinosaurs 3) Teachers are old 4) Dinosaurs went extinct 65.5 million years ago

Identify the structure in the cell that will produce atp from the starch building blocks

True or false: plant cell cytokinesis is different from animal cell cytokinesis because the contractile filaments found in plant cells are structures composed of carbohydrates and the cleavage furrow in animal cells is composed of contractile