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)
Answer:
The correct answer would be - Characteristics can be lost in evolution.
Explanation:
The new evidence helps in developing a new hypothesis. In this case, new evidence proved that the Chondrichthyes diverged after the evolution of bone had started instead of before the evolution started. This process called atavism where an ancestral genetic trait reappears after having lost. This leads to loss of the traits in the evolution
This can take place by knocking the mutation out to overriding the gene by the old gene or overriding the new trait by the old trait during the evolution period.
"F many scientists conduct the same or similar experiments, and all obtain similar results a 'Scientific Law or Theory' can be written, which is a generally agreed-upon statement that explains and predicts how a natural phenomenon works
Structurally, plant and animal cells are very similar because they are both eukaryotic cells. They both contain membrane-bound organelles such as the nucleus, mitochondria, endoplasmic reticulum, golgi apparatus, lysosomes, and peroxisomes. Both also contain similar membranes, cytosol, and cytoskeletal elements.
The right option is; They allow the body to react to stimuli.
Nerve cells, (also called neurons) are specialized cells that are found in their millions in the nervous system. Nerve cells are created to stimulate other cells in the body. They transmit messages in the form of electrical signals within the body, and they allow the body to respond to stimuli. Neurons are grouped into three types which are; sensory neurons, motor neurons and association neurons.