Biology, 31.03.2020 04:22, kenz70

Carbon dioxide makes up less than 1 percent of Earth's atmosphere, and oxygen makes up
about 20 percent. These percentages are maintained most directly by
A)
respiration and photosynthesis
the ozone shield
C)
synthesis and digestion
D)
energy recycling in ecosystems

Answers: 3

Show answers

Other questions on the subject: Biology

Biology, 21.06.2019 23:30, brook633

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2

Answers: 2

continue

Biology, 22.06.2019 07:00, okaiikk

According to the cell theory, which describes cells? a. all organisms are composed of multiple cells. b. all cells have the same structure and function. c. cells are found in everything on earth. d. living organisms are not created spontaneously

Answers: 2

continue

Biology, 22.06.2019 14:00, catherinethomas0826

To confirm when to exclude children from school it’s recommended that you refer to guidelines from which of the following organizations

Answers: 1

continue

Biology, 22.06.2019 14:30, 885122bah

What happens when a plant is losing too much water through transpiration? question 14 options: stomata open stomata close guard cells swell respiration increases

Answers: 1

continue

Do you know the correct answer?

Carbon dioxide makes up less than 1 percent of Earth's atmosphere, and oxygen makes up
about 2...