Conifer tree is the tree that the leaf is slender like needle, it is evergreen tree more, material is general softer, some contain colophony , reason calls soft material again, its grows in elevation 100 ~ 1500 meters commonly, have economy and ornamental value.Conifers appeared 280 million years ago before any other trees.Conifers are believed to be the oldest trees on earth。
Answer: Option B
Explanation: The thin layer that forms the outer covering of the cell is known as the cell membrane. It is composed of the lipid bilayer which as embedded proteins.
This membrane is selectively permeable which means it allows only specific molecules to pass through them.
The main function of cell membrane is to protect the cell from the outer environment and by the invasion of harmful bacteria and viruses.
Heredity is the passage of genetic information from one generation to another. For offspring to inherit traitsthere must be a reliable mechanism for transferring genetic information from one generation to the next.
<span>a)
</span>The milkweed is the primary producer in the
ecosystem. It manufactures food from the abiotic factors in the soil such as
nitrates and water and those in the atmosphere such as carbon-dioxide and
sunlight. The milk weed is then fed on by the caterpillar and a primary
consumer. The caterpillar is then fed on the mocking bird (secondary consumer)
<span>b)
</span>Increased human population growth and their activities
have resulted in the emission of carbon dioxide and other greenhouse gases in
the atmosphere. This has increased the global temperature. This increase of
global temperature increase ocean temperatures causing coral bleaching.
Another example is depletion of water sources
by human activities hence causing drought. Drought reduces the amount of
vegetation growth due to scarcity of water in the soil (due to lowering of the
water table) for plant growth.
