R R Rr is the result of 1st punnet square and the genotype used to produce f2
r
r
This is not a question. Do you need anything answered?
Explanation:
charles darwin proposed thoery of natural selection.he had collected imnumerable specimens of plant and animals.he published concept survival of fittest. while explaining he says that There is always competition for food.only those organism survive which shows adptations in various reasons. it thoery of natural selection.
There are some objections,
1. natural selection is not only factor responsible for evolution.
2. darwin did not mention uesful and useless modifications.
3. There is no explanation about slow and abrupt changes
Under ideal conditions, populations can grow exponentially. The growth rate increases as the population gets larger. Most populations do not live under ideal conditions and grow logistically instead. Density-dependent factors slow population growth as population size nears the carrying capacity.
Answer:
All of the statements are true.
The X chromosome is one of the two sex chromosomes of humans and some animals (the other sex chromosome is the Y chromosome). Men have a single X chromosome and women two X chromosomes.
Diseases whose gene is localized on the X chromosome are most often transmitted in the X-linked recessive mode; some are transmitted on the dominant mode related to the X.
In this mode of inheritance, the morbid allele behaves like a recessive trait.
Women heterozygotes are not affected but can transmit the disease; they are aid to be conductive of the disease.
The disese is only manifested in male subjects (XY) with only one copy of the gene (hemizygous subjects)