Answer:
The cholodny-went model was proposed in 1927. This model explains the capability of the shoots to grow in the direction of the sunlight whereas the capability of the roots to grow downwards. The hypothesis suggested that both these directional growth occurred due to the asymmetrical distribution of the plant hormone, auxin. This model has been modified a number of times by other scientists but its general concept is accepted by most of the researchers.
Answer:
A) boreal forest and tundra
Explanation:
Boreal forests are present north of 50-60 degree north latitude. Tundra biomes are also called as arctic tundra and are also located in extremes of the north latitude. Boreal forests are world' largest biome and stretches across both North America and Eurasia. So, the two habitats are found at high latitudes among the given options are: boreal forest and tundra.
Well they can begin as cosmic rays colliding with water molecules to create clouds. Hope this helps :)
Answer:
Lignin.
Explanation:
The structural integrity of plant spores is lignin that is present in many parts of the plant. This lignin provides hardness to the plant body which help them to stand the plant erect. If this lignin is not present in the plant body the plant will not stand erected. This lignin is present in large amount in the stem of plant body so that's why the lignin provides structural integrity to plant spores
