Some are thin areas where the primary wall is not covered by a secondary wall and are populated with plasmodesmata known as

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#Question id: 15154

#Unit 8. Inheritance Biology

In this problem we will explore some of the many ways that mutations in two different genes can interact to produce different Mendelian ratios. Consider a hypothetical insect species that has red eyes. Imagine mutations in two different unlinked genes that can, in certain combinations, block the formation of red eye pigment yielding mutants with white eyes. In principle, there are two different possible arrangements for two biochemical steps responsible for the formation of red eye pigment. The two genes might act in series such that a mutation in either gene would block the formation of red pigment. Alternatively, the two genes could act in parallel such that mutations in both genes would be required to block the formation of red pigment.

Further complexity arises from the possibility that mutations in either gene that lead to a block in enzymatic activity could be either dominant or recessive. If the crosses between a wild type insect with red eyes and a true breeding white eyed strain with mutations in both genes. Such considerations yield the Pathways in parallel with a recessive mutation in one gene and a dominant mutation in the other, determine the phenotype of the F1 progeny and the expected phenotypic ratio of red to white eyed insects in the F2.

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#Question id: 1420

#Unit 4. Cell Communication and Cell Signaling

Examination of a cell’s structure reveals condensed chromatin, a shrunken cytoplasm, but unfragmented DNA and a lack of blebbing. If this cell has been triggered to undergo apoptosis by an extrinsic factor, which of the following events has NOT likely happened yet?

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#Question id: 29036

#Unit 11. Evolution and Behavior

Darwin’s hypothesis is that Exaggerated secondary sexual traits are favoured by sexual selection because they increase male mating success but more than higher exaggeration secondary sexual traits that leads to___ 

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#Question id: 7163

#Unit 5. Developmental Biology

What statement is correct when comparing morphallaxis and epimorphosis?

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#Question id: 31258

#Unit 5. Developmental Biology

In salamanders, regeneration blastema formed from: