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neonofarm [45]
2 years ago
9

In humans, the yolk sac ________. in humans, the yolk sac ________. is the site of origin for blood cells and primordial germ ce

lls is no longer a useful structure forms the human urinary bladder passes nutrients to the embryo after digesting the yolk mass
Biology
1 answer:
aleksklad [387]2 years ago
8 0

In humans, the yolk sac is the site of origin for blood cells and primordial germ cells. The human yolk sac is a membrane located outside the embryo and it is connected by a tube through the umbilical opening to the embryo's midgut. The yolk sac serves as an early site for the formation of blood and in time, is incorporated into the primitive gut of the embryo.






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6 0
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What combinations of alleles could result from a crossover between BD and bd chromosomes?
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Answer:

Bb, Db , Bd and Dd

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When a cross between two parents (having certain trait) is carried out , they share their alleles with each other to produce offspring with new traits. These offspring have gentically different allele combination as compared to their parents. A  genetic cross can be represented by a punnet square (as given below)

The cross between two parents with genotype "BD" and "bd" will result into the following offspring -

B D

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Answer: dandelion is consumed by bees, grasshoppers, and butterflies.

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