A researcher conducted crosses between two different strains of Drosophila. When true-breeding flies with singed bristles (s) an
d normal wings (L) were crossed to true-breeding flies with normal bristles (S) and vestigial wings (l), all F1 offspring had normal wings and normal bristles. The F1 offspring were crossed to flies with singed bristles and vestigial wings. Which F2 offspring is/are recombinant? (A) Singed bristles/vestigial wings only
(B) Singed bristles/normal wings only
(C) Singed bristles/normal wings and normal bristles/vestigial wings
(D) Singed bristles/vestigial wings and normal bristles/normal wings
Singed bristles/vestigial wings and normal bristles/normal wings
Explanation:
The recombinant progeny might occur due to the crossing over of the homologous chromosomes in case of the linked genes. This progeny are different from their parent progeny.
The F1 offspring obtained from the given cross in the question results in the normal wings and normal bristles ( SsLl). This progeny was crossed with singed bristles and vestigial wings (ssll). The progeny obtained from their cross are 'Sl' and 'sL' ( parental type ) and SL' or 'sl' ( recombinant).
The trait that would best indicate that a particular arthropod was a member of subphylum chelicerata is that it possess two body segments instead of three;
A fused head and thorax (cephalothorax), and an abdomen (opisthosoma).
Their segmented body with jointed limbs is covered in a cuticle made of chitin and proteins.
Proteins are made up of amino acids, or organic compounds, that are linked together through peptide bonds. Different combinations of these amino acids make up all of the proteins you can think of, from the fibrin that forms scabs on a cut finger to a protein that allows rattlesnakes to detect body heat
Proteins are long chains of amino acids.In other words, amino acids are like the links in a chain.The chain itself represents the protein molecule. Protein chains are then twisted and folded together in specific ways to create certain molecules
Proteins are one of the four different types of macromolecules, in addition to carbohydrates, lipids, or fats, and nucleic acids, such as DNA and RNA. Macromolecules are large molecules that perform specialized functions inside living organisms. The structural arrangement of a protein molecule will differ in accordance with its function