When Lucifer yellow, a small dye, is injected into a neuron of the retina, neighboring neurons become rapidly labeled. If the retina is incubated in dopamine prior to Lucifer yellow injection, only the injected neuron becomes labeled. These findings suggest which of the following?

I. Neurons of the retina communicate via gap junctions.

II. Dopamine is transferred between cells via gap junctions.

III. Dopamine decreases the permeability of gap junctions.

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#Question id: 15376

#Unit 13. Methods in Biology

If a protein made up of three subunit α₂βγ (Mr. of α = 25000, β = 50000, γ = 75000) which of the following correctly representing SDS and Native (buffer) gel

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#Question id: 15378

#Unit 8. Inheritance Biology

You find a pink geranium in your flowerbed of red geraniums. Seeds from self fertilization of this plant produce ¼ red plants, ½ pink plants, and ¼ white plants. When considering the visible phenotype, which explanation is most likely?

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#Question id: 15379

#Unit 8. Inheritance Biology

What are the possible offspring from a type A mother and a type AB father?

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#Question id: 15380

#Unit 8. Inheritance Biology

In soybeans, resistance to sudden death syndrome (SDS) is inherited as a dominant condition. In some cases, individuals that are not resistant to SDS (but whose parents were) can pass the trait on to their progeny. This is an example of which of the following?

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#Question id: 15381

#Unit 8. Inheritance Biology

Neurofibromatosis is a condition in humans which is generally inherited in a dominant fashion. Assuming this disorder is 90% penetrant, what is the chance that a single child born to a father with neurofibromatosis and a mother known not to carry the mutation will have the disorder?

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#Question id: 15382

#Unit 8. Inheritance Biology

In a group of fruit flies homozygous for an allele that causes a reduced number of thoracic bristles, you notice that the number of bristles varies from about half the normal number to only a few bristles. This is an example of which of the following?