Most plants have roots, but there are some
exceptions. The exceptions are bryophytes
and the groups of green algae that are
classified as plants. Bryophytes have rootlike
structures called rhizoids for absorbing
water, but because rhizoids lack vascular
tissue they are not considered roots.
The controlled experiments are performed by the scientists, when they want to study the changes in the sample on changing a single variable. So, the correct answer is option (b).
In case, all variables are kept same, no changes would be observed in the experiment sample. A controlled experiment can be performed on living thing as well as non living. But, controlled experiment cannot be performed on the things which are influenced by a lot of variables, as they cannot create realistic results. So, the option (a), (c), and (d) are incorrect.
Answer:
Tundra
Explanation:
Ocean is the most stable biome, provides the majority of earths food and oxygen.
Rainforest provide 20% of earths food production. Also stable.
Grasslands although the don't get much rain it doesn't compare to the harsh weather that Tundra's face.
Tundra's is a very fragile environment. The freezing cold temperatures makes it a very difficult environment to survive in the winter, and plants and animals have a hard time coping with any extra stresses and disturbances. Therefore making it the least stable out of the rest listed.
Plants absorb the water from the soil ( through their roots) and then release it back into the atmosphere by transpiration (evaporation from the leaves)
I think the answer to this is 2.