When crossing over occurs, part of a chromatid on one chromosome breaks off and switches positions with the matching portion of a chromatid on the homologous chromosome. How does crossing over affect the possible genetic combinations in the offspring formed from these gametes?
A) Crossing over increases the number of possible genetic combinations in the offspring.
B) Crossing over has no effect on the possible genetic combinations in the offspring formed.
C) Crossing over affects only the possible genetic combinations that occur in identical twins.
D) Crossing over decreases the number of possible genetic combinations in the offspring.
Ans: A) Crossing over increases the number of possible genetic combinations in the offspring.
You might also like to view...
Chaparral is
A. a type of shrubland/grassland. B. a type of forest. C. restricted to serpentine soils. D. widespread in Africa. E. distinguished by tall trees.
Of the following sequences, which one reflects the best scientific knowledge about the succession of Homo species from the past until the present?
A. Homo heidelbergensis ® Homo habilis ® Homo sapiens ® Homo erectus B. Homo habilis ® Homo heidelbergensis ® Homo erectus ® Homo sapiens C. Homo heidelbergensis ® Homo sapiens ® Homo erectus ® Homo habilis D. Homo sapiens ® Homo heidelbergensis ® Homo habilis ® Homo erectus E. Homo habilis ® Homo erectus ® Homo heidelbergensis ® Homo sapiens
The derived sequence is
The following fragments of DNA correspond to a section of the genome. ACTGT GTGTT GACTC TTCAAC ACTGA TGAC A) C T C A G T C A A C T T G T G T C A B) T G A C A C A A G T T G A C T G A G C) A C T G T G T T C A A C T G A C T C D) A C T G T G T G T T G A C T C T T C A A C A C T G A T G A C
Chlorophyll a is the most common photosynthetic pigment in plants. It's abundance gives plants their green color. This is because it:
a. absorbs light of low wavelengths (400-500 nm) b. reflects green light c. absorbs yellow and blue light d. absorbs green light e. is a translucent pigment which does not influence the color of the plant