When it comes to population evolution and genetics, we cannot fail to cite the Hardy-Weinberg principle which emphasizes that if evolutionary factors such as natural selection, mutation, migration and genetic oscillation do not act on a particular population, the frequencies genotypic proportions will remain constant.
The five requirements for a population to be in Hardy-Weinberg equilibrium are:
- Large-scale breeding population: For a population to be in Hardy-Weinberg equilibrium, it is important that this population is large, as small populations favor genetic drift (unanticipated fluctuations in allele frequencies from one generation to another).
- Random mating: In order for the Hardy-Weinberg equilibrium to occur, it is necessary that the mating occur at random, with no preference for certain groups within the population. In this case, we say that the population is in panmixia, that is, they all mate at random.
- No mutations: Mutations alter the total alleles present in a population (gene pool). Therefore, in a Hardy-Weinberg equilibrium population, no mutations should occur.
- No gene flow: When there is gene flow due to migration or immigration of individuals, some genes may be included or excluded from the population. Thus, in an equilibrium situation, no gene flow occurs.
- Lack of natural selection: For a population to be in Hardy-Weinberg equilibrium, natural selection must not be acting on it. If natural selection acts, some genotypes will be selected, modifying the allelic frequencies of the population.
Answer:
by which large pieces of food are cut and crushed into
by which large pieces of food are cut and crushed intosmaller pieces is called:
d. mechanical digestion
5. The tube that connects the mouth to the stomach is the:
a. oesophagus
5. The hard, outer coating of the tooth is called:
b. enamel
- The building blocks of proteins are:
c. amino acids
5. Which of the following vitamins is made by the body?
a. vitamin D- b. vitamin A c. vitamin C
. Having too little of the mineral iron can cause:
b. goitre
The wavelike motion that moves food through the digestive tract is called:
d. peristalsis
Gastric juice contains all of the following except:
d. bile
The process by which large food molecules are broken down into smaller food
The process by which large food molecules are broken down into smaller foodmolecules is:
c. mechanical digestion
Fats are digested in the:
b. small intestine
Poor nutrition caused by an unbalanced diet is called:
c. malnutrition
The fingerlike projections on the lining of the small intestine are called:
b. villi
There are so many species in the millions of years discovering each one. Classifying is one way that organizes all types of species into categories, knowing what they are, their characteristics, their habitat, etc
C.2
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Answer:Both on the leading strand and on each okazaki fragments of the lagging strand.
Explanation:
A primer is a short single-stranded RNA nucleotide that initiate DNA synthesis at the replication fork. Because DNA polymerase can not initiate replication on it own short strand of RNA primer synthesized by an enzyme RNA primase is needed to initiate DNA polynucleotide synthesis.
RNA primer is present on both leading and lagging strand.
RNA primer of about 10 nucleotides long are present on the leading strand and on each okazaki fragments on the lagging strand to initiate replication. The RNA primer is removed and replaced by DNA nucleotides by DNA polymerase.
