Answer:
The phenotypic ratio will be 3:1
Explanation:
As per this question there are two phenotypes for seed color, yellow and green. Both the parents are true breeding that means they are homozygous for this trait. Also, all the F1 plants have yellow seed color which clearly indicates that yellow seed color is a dominant trait while green is recessive trait.
The cross of true breeding plants as mentioned above is depicted as under:
Parents YY x yy
/ \ / \
F1 generation Yy Yy Yy Yy
So, as per the law of dominance because of the presence of Y allele, all these progeny will be yellow in color.
Next, when these F1 plants will be crossed, the result will be as under:
F1 generation Yy x Yy
/ \ / \
F2 generation YY Yy Yy yy
The genotypic ratio of F2 generation is 1:2:1
The phenotypic ratio of F2 generation is 3:1
It simply means that in F2 generation, 3 progeny which have allelic combination YY & Yy will be yellow colored while 1 progeny which has allelic combination yy will have green color.
Answer:
Explanation:
The first mass extinction is called the Ordovician-Silurian Extinction. It occurred about 440 million years ago, at the end of the period that paleontologists and geologists call the Ordovician, and followed by the start of the Silurian period. In this extinction event, many small organisms of the sea became extinct.
The continuous, low-level extinction of species is referred to as mass extinction.
- A widespread and quick decline in the diversity of life on Earth is known as an extinction event.
- A sudden shift in the diversity and abundance of multicellular creatures serves as a telltale sign of such an occurrence. It happens when the rate of diversification outpaces the rate of extinction.
- A mass extinction event occurs when a species disappears far more quickly than it is replaced.
- This is typically understood as the loss of almost 75% of all species over a "short" period of geological time, or fewer than 2.8 million years.
- The Cretaceous-Paleogene extinction, sometimes known as the day the dinosaurs died, is the most well-known of all the mass extinction events.
learn more about mass extinction here: brainly.com/question/1048615
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Answer:
The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat.
Explanation:
The answer would be A. the arrangement of DnA
