Answer: The sequence of events of avocado seed germination includes:
Water absorption --> enzyme activation --> radicle emerges --> lengthening of the hypocotyl --> growth of epicotyl and plumule development --> shrinking of the cotyledons.
Explanation:
Germination is defined as all the changes that occurs when a seed embryo resumes it's growth and development to become an independent seedling. Seeds usually germinate in two ways:
--> EPIGEAL germination: in this type of germination, the hypocotyl grows rapidly and elongates, carrying the cotyledon above the soil.The AVOCADO seed is a typical example of a dicotyledonous plant.
The sequence of events of avocado seed germination starts by imbibition which is the rapid in take or absorption of water by the seed through osmosis. Hydration of the embryo activates the enzymes in it which converts insoluble stored food materials into soluble forms. The testa splits and the radicle emerges first. It grows downwards as the primary root from which root hairs and branch roots arise( to form a tap root system). Next, the hypocotyl lengthens, pushes its way up through the soil carrying with it the cotyledons and the plumule. The cotyledons turn green on exposure to sunlight and start to photosynthesize. The epicotyl then grows and the plumule develops into a green shoot. By the time the first foliage leaves grow and begin to photosynthesize, the cotyledons shrink and drop off.
Answer:
C
Explanation:
C. there is an even distribution of K+ and Na+ ions inside and outside the cell.
IF THIS IS THE COMPLETE QUESTION WITH MULTIPLE CHOICE.
Two genes interact to produce various phenotypic ratios among F2 progeny of a dihybrid cross. Design a different pathway explaining each of the F2 ratios below, using hypothetical genes R and T and assuming that the dominant allele at each locus catalyzes a different reaction or performs an action leading to pigment production. The recessive allele at each locus is null (loss-of-function). Begin each pathway with a colorless precursor that produces a white or albino phenotype if it is unmodified. The ratios are for F2 progeny produced by crossing wild-type F1 organisms with the genotype RrTt.
9/16 Dark Blue 6/16 light blue 1/16 white
A) At least one copy of each dominant allele results in dark blue, at least one copy of either dominant allele produces light blue, and the absence of both dominant allele produces white.
B) If both dominant alleles are present, the result is dark blue. At least one copy of one specific dominant allele is required for light blue. If that dominant allele is not present, the result is white, regardless of whether the other dominant allele is present.
C) At least one copy of both dominant alleles results in dark blue; at least one copy of one of the dominant alleles also results in dark blue, but at least one copy of the other dominant allele produces light blue; and the absence of either dominant allele produces white.
MY ANSWER IS:
A) At least one copy of each dominant allele results in dark blue, at least one copy of either dominant allele produces light blue, and the absence of both dominant allele produces white.
Answer:
D. A number of genetically resistant pesticide survivors reproduce. The next generation of insects contains more genes from the survivors than it does from susceptible individuals.
Explanation:
Insect populations already have some insects with pesticide resistance genes. Exposure of insects to pesticides results in the natural selection of these insects with pesticide resistance as they are able to survive and reproduce in the presence of pesticides whereas the other insects die. The resistant insects leave more progeny resulting in the evolution of insect population with increased frequency of pesticide resistance gene.