Answer:
Food chain shows only one part of animal and the food they consist of while food web shows different animals and different type of food they eat. Food chain is part of food web
Structure X is only found in plant cells, and structure Y is found in plant and animal cells.
Answer:
C
Explanation:
There was no C and D on yours but here is a picture of my son's exam.
Answer:
Either on 12th June or 14th
Explanation:
The measure of variation which exists in the genetic makeup of any particular individual within a population is genetic variation. There are several key features and advantages associated with the genetic variation as it is an important factor causing evolution allowing natural selection thus leading to increase or decrease the frequency of alleles in a population.
The other factors causing genetic variation include random mating, mutation, random fertilization and recombination during meiosis between the homologous chromosomes.
The main advantage of genetic variation is it enables the individuals to adapt to environment as well as maintaining the survival of the population.
Based on the information on genetic variation we can conclude whether there is increase or decrease in the genetic variation of the population in the gene pool.
• A zebra migrates to join a different herd of zebras- Increase
• Competition for sunlight leads to taller trees- Decrease
• The DNA of a snake changes to make its venom stronger- Increase
• A grass-fire randomly sweeps through a population of buffalo and kills most of the animals- Decrease
