A weakened immune system may be caused by what?

The type and amounts of plants that grow in an ecosystem heavily depend on the average precipitation levels and length of the growing season. how would these factors be classified

Which of these is NOT a stage where water can stay for many years as it travels through the water cycle? A. ice caps B. the ocean C. groundwater D. surface runoff

How does nuclear fusion differ fundamentally from nuclear fission? A. Nuclear fusion is a cold process. B. Nuclear fusion splits atomic nuclei. C. Nuclear fusion combines atomic nuclei. D. Nuclear fusion doesn't produce energy.

Why are recessive x-linked traits seen more often in human males than in human females? (select all that apply.) ?

Which animal is an ectotherm? 1 kangaroo 2 whale 3 eagle 4turtles

Which of the following is NOT an argument used against genetically modified food? (A) It is new technology that unnaturally breaks genetic barriers between species (B) It might cause allergic reactions. (C) Humans should not be designers of life.

In multicellular organisms, cells are arranged into groups that work together to perform a common function. What are these groups called? bones joints systems tissues

What substances move freely through the shell of the egg?

Hemoglobin and enzymes are: A. lipids B. proteins C. carbohydrates D. nucleic acids

How would the introduction of a nonnative species most likely affect biodiversity in an ecosystem? a. The nonnative species would decrease biodiversity. b. The nonnative species would increase biodiversity. c.