Answer:
homo-zygous lethal dominant
Explanation:
A homo-zygous lethal pattern is a type of inheritance where an allele is lethal in homo-zygous individuals. In normal dominance, the expected genotype ratio when F1 heterozygous individuals are crossed is 1:2:1 (i.e. 1 homo-zygous dominant: 2 heterozygous individuals and 1 homo-zygous recessive), while the phenotypic ratio is 3:1 (3 individuals expressing the dominant allele: 1 individual only expressing the recessive allele). In this case, the homo-zygous lethal allele changes the expected F2 phenotypic ratio to 2:1 (i.e., 2 heterozygous singing Beetles : 1 homo-zygous recessive non-singing Beetles), where the partially dominant allele is lethal in homo-zygous individuals.
The blood vessels farthest from the heart must have valves.
The valves which are present in the blood vessels prevent the backflow of the blood back into the specific organ.
There are different valves present in the heart are:
- The tricuspid valve is situated between the right atrium and right ventricle.
- The pulmonary valve is between the right ventricle and the pulmonary artery.
- The mitral valve is between the left atrium and left ventricle.
- The aortic valve is between the left ventricle and the aorta.
Other vales which are present in the blood vessels are in leg. Leg veins do require the valves. If not present the blood will go back down into the feet because of the gravity. Thus there are various valves present in the leg veins.
Valves in veins are bicuspid, meaning they have two flap-like structures that regulate blood flow in the vein.
To know more about the Valves, refer to this link:
brainly.com/question/12926213
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Answer:
Tectonic plates.
Explanation:
The continents are embedded in the plates, like logs in the ice of a frozen river. As the plates move, the continents move with them. When two continental plates meet, one is dragged down beneath the other.
A reduction in sea ice due to climate change has negatively affected the food abundance of Penguins.
Explanation:
- Sea ice is ocean water frozen blocks. Unfortunately, rather than most other areas, climate change impacts Antarctica.
- If the temperatures on the surface of air and water rise, the sea ice melts. This leads to many marine mammals and seabirds losing their habitat and food supply, including Adelie penguins.
- The biggest threat to the penguins stems from changes in the Antarctic sea-ice cover, that will affect its feeding and breeding.
1st one i think, hope that helped
