Answer:
B. He has no E alleles.
Explanation:
In order for the boy to have an attached earlobes phenotype, he must have no E alleles, because the E is dominant. So his genotype must be ee. If he has even just a single E allele (like Ee) he will have detached earlobes, because the dominant trait will mask the expression of the recessive trait.
Why not A or D: Heterozygous Ee (one of each allele) would result in detached earlobes.
Why not C: If he has no recessive alleles, EE, he would have detached earlobes.
DNA, ribosomes, cytoplasm
A cellular organelle is a structure in the cell that performs a specific function.
Nucleus - stores cell's DNA; DNA replication occurs here
Ribosome - produce protein; "factories" of the cell
Mitochondria - breaks down food for energy to be used by the cell; "powerhouse" of the cell
Vacuole - store materials such as food, water, sugar, minerals, and waste products
Endoplasmic reticulum - carry materials throughout the cell; "transport system"
Answer:
The answer is A
Explanation:
There are certain types of proteins that need to be sinthesized in the rough ERC in order to reach its final destination. These proteins are:
- Proteins that need to be exported from the cell.
- Proteins that need to be docked to either endomembranes or the plasma membrane.
- Hydrolytic lysosomal enzimes.
- Proteins that have a function in the lumen of certain organelles such as the endoplasmic reticulum, golgi or the nuclear envelope.
Hemoglobin doesn't fit in any of these cateogories, given that it is a cytoplasmic protein. Therefore, its synthesis begins and ends in the cytoplasm, where the protein performs its function.