What does a round cross-section of a long bone suggest?

True or False: Organisms are classified and placed into kingdoms based on their characteristics

A population of tree frogs lives in a forest. A river runs through the middle of the forest. A particularly snowy winter is followed by an unusually rainy spring.

Polar bears who have white fur and live in the Arctic must use which of the following adaptations a mimicry b. counter shading camouflage d. variation

Which cells in the leaf are green? A. phloem cells B. mesophyll cells C. lower epidermis cells D. upper epidermis cells

Are virus considered liveing organisms

Oxygen (O) atoms have six valence electrons and beryllium (Be) atoms have two valence electrons. Which of the following is the correct formula for a compound made of oxygen and beryllium?

The presence of cholesterol in the plasma membranes of some animals (A) enables the membrane to stay fluid more easily when cell temperature drops. (B) enables the animal to add hydrogen atoms to unsaturated phospholipids.

A landslide is a natural hazard that is usually related to the instability of a slope. Human activities can directly influence the occurrence of landslides. All but one would be considered a human cause. That is

Petra is at the fourth month of her pregnancy. Her unborn child is now referred to as a (n) :

Tension force is an example of a contact force true or false