Smoking and lung cancer is it a correlation or causal

How many protons are in Cesium-135 (Cs) ?

Grass - > Grasshopper-> Mouse - > Hawk If there's 10,000kg of biomass available at the producer level, how much biomass is available for the secondary consumer? And who is the secondary consumer?

Human pathogens are select one: a. mesophiles. b. thermophiles. c. psychrotrophs. d. psychrophiles.

Why are fixed pieces of equipment, such as bouncy seats, high chairs, and playpens, detrimental to an infant's development?

Self-fertilization is avoided in sponges because a. there is no way for sperm to enter the sponge. b. the sperm do not possess the enzyme needed to penetrate the egg. c. sperm and eggs are not produced at the same time. d.

Which of the following statements about amphibians is true? A. Amphibians are represented by about 500 species of frogs, toads, and salamanders. B. Populations of amphibians in a few local areas have declined dramatically in the last few decades. C.

True or False. Osmosis is an active process of the cell.

The part of a galaxy not made up of stars or dark matter is largely

Among human population, most fresh is used for

What is ecology? what are the levels of biological organization from smallest to largest?