The lab setup shows four test tubes. Tube 1 contains water only. Tube 2 contains a live snail. Tube 3 contains a live green water plant. Tube 4 contains both a live green water plant and a live snail. In this setup, which tubes contain at least one organism carrying on cellular respiration?
A) Tubes 1 and 2 only.
B) Tubes 2 and 4 only.
C) Tubes 3 and 4 only.
D) Tubes 2, 3, and 4 only.

Vegetation that grows along the floors of tropical and temperate forests is called undergrowth. how is the undergrowth of a tropical rain forest most likely to differ from the undergrowth of a temperate forest? a. a tropical rain forest's undergrowth most likely experiences periods of dormancy during colder weather. b. a tropical rain forest's undergrowth most likely experiences periods of dormancy during rainy weather. c. the undergrowth of a tropical rain forest most likely requires less sunlight. d. the undergrowth of a tropical rain forest most likely requires more sunlight.

Were does condensation occur? a) hydroshereb) lithosherec) boishered) atmosphere

Question 17 (1 point) where does penicillin come from? a. it is a chemical that man invented b. it is a fungus c. it is a toxin made by other bacteria d. it was discovered in archaebacteria