Answer:
The correct option is <em>3. they break down rock into soil in which plants can grow</em>
Explanation:
When a disaster is such huge that even the soil and organic matter get removed from the place, then the succession that will occur in such kind of place will be termed as primary succession. For example, a volcanic eruption or an earthquake.
On the other hand, if after a disaster some of the organic matter remains on the land, then the succession that will occur will be termed as secondary succession. E.g a succession after fire
In primary succession, the pioneer species will be plants that require less soil such as the lichens. The lichens will break down the rocks into the soil and eventually new species of plants will start to grow on the land.
Answer:
D. Spinal nerves have mixed motor and sensory function.
Explanation:
spinal's nerves are mixed nerves, which means that they carry sensory and motor information. They carry sensory information to the central nervous system to give a motor answer that will travel through the spinal nerves to specific muscles. The White matter, which is peripheral in the spinal cord, contains axons while the gray matter, which is central in the spinal cord, contains cell bodies.
Answer:
There are many invasive animal sand plants which are harmful for native flora and fauna. Some of the invasive or alien species are as following:
<u>1. The Nile Perch:</u><em> </em>Nile Perch is a type of fish which is native to African lake and river systems but if it is introduced in other countries lake it can be dangerous to other fishes in that lake. It was earlier introduced to Lake Victoria but after sometime it was evaluated that native fishes got extinct and the Nile Perch become very huge in size.
<u>2. The cotton whitefly: </u> Cotton whitefly are native to India but now can be found on most of the continents and have very bad impact on the fauna or agricultural plants. They have capability of transmitting upto 100 different plant viruses. find them thriving
<u>3. The desert locust:</u> The desert locust is a species of locust which can fly and are one of the most disastrous migratory pests in the world. They feed over green green vegetation, including pasture, crops and fodder. They have very bad impact on native flora as they are migratory pests. They are found in Africa and migrated to nearby countries such as India and damages the native flora.
<u>4. European starlings:</u> European starlings are the bird species which fight with native species for food and shelter. They are found in Alaska and Mexico and proved invasive in U.S. as the number of native birds decreased with their introduction.
Animal cells (which are Eukaryotes) contain a nuclues, while Bacterial cells (which are Prokaryotes) do not contain a nucleus.
