Answer:
mutation in DNA
Explanation:
Mutations are changes in the genetic code that can occur in many ways. Each time a cell divides, say, DNA must be copied into two copies, one copy for each new cell. Although this copying is very precise, it is still not perfect - for about every billion accurately copied databases, one is mistranslated.
Another source is DNA damage, which can occur spontaneously through the normal life of the cell, or through external toxins or negative influences (ultraviolet radiation, for example). Through evolution, cells have developed a very complex system for repairing changes in DNA, but these systems not only have limitations but can sometimes cause additional errors themselves.
Answer:
Water pollution may be defined as the contamination of the unwanted substance or pollutant with water that changes the normal characteristics of water. Three main contributors of ground water are as follows:
Chemical farming: The use of pesticides and fertilizers in the fields and its direct run off in river and groundwater causes the water pollution.
Industrial waste: The industrial waste consists of harmful chemicals and heavy metals. The direct discharge of chemical waste in the lakes, ground water and ponds makes the water dirty and causes water pollution.
Effluent from waste water treatment plant: The effluent and the harmful chemical waste release from the waste water treatment plant is the major contributor to the ground water. The effluents mix with the ground water and changes the ground water property.
Answer:
We could use up all of them right away and not have the resources for humans and animals to survive.
Explanation:
Right now, we are using our natural resources at a consistent rate. We sometimes use to many of them in one day. If we continue using up our natural resources at the rate we are right now. We may not have the necessary resources to survive in about 10-20 years.
Hope this helps!
Answer:
1. Meiosis 1.
2. Meiosis 2.
3. End.
4A. The chromosome theory of inheritance states that chromosomes are the main carriers of the genetic factors responsible for inheritance.
B. Body cells have two sets of chromosomes while sex cells have one set. Therefore, when two sex cells meet, they form an embryo with two copies of each chromosomes thereby producing a body cell with the exact number of chromosomes. In essence, meiosis maintains the right number of chromosomes of body cells by creating half the number of chromosomes of sex cells.
C. Meiosis.
Explanation:
