Introduced species can harm our planet because in some regions of the world we are not prepared for their type of species, which can all in all cause damage.
Answer: There are many sources of light, but the initial energy for all light sources comes from the sun. Light travels away from its source in straight lines through space as waves of energy. The waves we can detect with our eyes are called visible light. Patterns in the behavior of light are predictable because light moves in waves through space until it comes in contact with an object or material that changes its direction. Light can pass through or bounce off objects. Additionally, different materials can block or absorb light. If an object blocks light, a shadow of the object forms. If the intensity or direction of the light source changes, the appearance of an object’s shadow can change in size, shape, or darkness. Absorbing light energy can cause changes in matter. A common example includes the color of paper or fabric fading as the matter absorbs light over time. Vibrations cause sounds. We can hear when sound waves travel through the air to our ears and cause our eardrums to vibrate. Sound can also travel through other forms of matter, such as liquids and solids.
Explanation:
Answer:
B) There is an increase in the number of giraffes with long necks in areas of Africa where low-growing trees have died
Explanation:
The directional selection is one of the ways of the natural selection in which the natural selection selects or favours the most extreme trait of the species and the extreme trait show higher fitness than the normal or average trait.
In the given question, the case of Giraffe necks shows directional selection as the normal length of the neck is not favoured by the environment but the extreme trait that is long neck is favoured by the environment and the selection shifted to that level.
Thus, Option-B is the correct answer.
Answer:
False
Explanation:
The poles are covered by Ice at most seasons of the year