Answer:
Genotype ratio: 1, 1:1, 1:2:1
Phenotype ratio: 1, 3:1
Explanation:
Single gene pair cross is also known as monohybrid cross. This means that only one gene usually with two alleles is observed and it express one trait.
For example, if we name the gene for a certain trait with A, the possible genotypes are AA (dominant homozygous), aa (recessive homozygous) and Aa (heterozygous). Possible crosses are:
P: AA x AA
F1 : all of them are AA
The same is with aa x aa (all of the offspring are with aa genotype)
P: AA x Aa
F1: AA Aa AA Aa (genotype ratio 1:1) (phenotype ratio 3:1)
The same genotype ratio is in aa x Aa (offspring will have aa Aa aa Aa-(genotype ratio 1:1) (phenotype ratio 1:1)
P: Aa x Aa
F1: AA Aa Aa aa (genotype ratio 1:2:1) (phenotype ratio 3:1)
P: AA x aa
F1: Aa Aa Aa Aa (1)
TRUE. the placenta develops in the mother's uterus during pregnancy. The structure provides oxygen and nutrients to the growing baby and removes waste products from the babys blood
Answer:
Zika virus and West Nile virus are the two pathogens which causes more diseases due to increase the population of mosquito.
Explanation:
Zika virus belongs to the family of Flaviviridae. Aedes mosquitoes which are active at day time are the carrier of this virus. West Nile virus is also spread through the bite of mosquito. The infected mosquito is the main cause of spreading of this disease. This virus is spreading too fast in the United States of America in the summer season where the population of mosquitoes increases.