Answer:
Explanation:
In gene transfer, researchers introduce a foreign gene directly into cancer cells or into surrounding tissue. The goal is that the newly inserted gene will cause the cancer cells to die or prevent cancer cells and surrounding tissue from funneling blood to tumors, depriving them of nutrients they need for survival.
The taiga biome is the largest terrestrial biome and extends across Europe, North America, and Asia. It is located right below the tundra biome. The taiga biome is also known as coniferous forest or boreal forest. This biome typically has short, wet summers and long, cold winters. Precipitation is moderate in the taiga. It gets plenty of snow during the winter and plenty of rainfall during the summer.<span>Interesting Taiga Biome Facts:Fires are very common in the taiga biome. These fires are necessary to help rid the area of old and sick trees.There is not much variety in plants. Majority of the plants are conifer trees which is why the taiga is referred to as the coniferous forest.The conifer trees in the taiga biome are referred to as evergreen. This means they remain green all year round and never drop their leaves.<span>Because evergreen trees do not drop leaves, there is nothing to keep the soil in the taiga full of nutrients. This is the reason why there is not much variety in the vegetation. </span>Softwood timber is used to make paper. Majority of softwood timber comes from the taiga biome.<span>Although two major cities, Toronto and Moscow, are located in the taiga biome, most of this biome is uninhabited by people. </span>The taiga biome is very cold during the winter. Temperatures can reach as low as -60° F.For six months out of the year, the temperature in the taiga biome is below freezing.Plants can only grow during the summer when temperatures are favorable. This growing season only lasts about three months.Many animals of the taiga biome have to migrate to warmer areas or hibernate during the long, cold winters.Animals of the taiga have many specialized adaptions including lots of thick fur or feathers and the ability to change colors during different seasons.Scientists believe that the taiga biome was completely covered by glaciers many years ago.The taiga forests are endangered due to logging and mining by humans. When trees are cut down in the taiga, it takes a very long time to restore itself because of the very short growing season.Although there are not many animals in the taiga biome, it inhabits millions of insects. Birds migrate there to feed off these insects every year.<span>The temperature change in the taiga is extreme. It is either summer (hot) or winter (cold). The spring and fall are too short to notice.</span></span>
Answer:
B. often use tube feet to move around in their environment
Explanation:
Tube feet are tiny tubular projections of echinoderms on the underside (oral side). They are a member of the echinoderm water vascular system.
Tubular feet are used for feeding, breathing and shifting. They are arranged around the sides, in grooves. They work by hydraulic pressure. They are used to transfer food in the centre to the oral mouth, and may stick to surfaces. Tube feet allow certain animals to stick and travel slowly to the ocean floor. for example starfish uses tube feet for the above functions.
Hence, the correct option is B.
I believe that it consists of about 3 billion letters/base pairs
