The fossil records of primitive plants show a variety of seed dispersal mechanisms that has been adopted by plants at various stages and how they have evolved. The most primitive of this seed dispersal mechanism is the Anemochory
Anemochory is the dispersal of seed through the wind. The seeds have wing like structures and are lightweight to be able to fly away with the wind. They are dull colored and are pale that will prevent the seed from being visible.
Hydrochory is the next order of evolution of the seed dispersal mechanism which became majorly adopted by plants that tend to grow near water sources and those whose seeds are too heavy to fly in the air. One of the best examples is the coconut that falls off on the sea water in the coastal areas and floats to other lands and sprouts to a new plant.
Barochory is the dispersal of the seed through gravity. This is the mechanism where the fruit falls off to the ground due to gravity and grows into a new plant.
Endozochory is the dispersal of the seed through animals. In this case the seed is usually covered with a fleshy edible part which is consumed by the animals and in this process the seed goes into the digestive system of the animal and is excreted in a different place from where the seed can sprout into a new plant.
Ballochory is the dispersal of the seed due to the forceful ejection of the seed by explosive dehiscence of the seed. This lets the plant to place its seeds in a distant area. One of the best examples is the Hura Crepitans which is also called the dynamite tree, named after its exploding fruits.
Answer:
Write a lab report that summarizes his experiment
Answer:
Negatively repressible.
Explanation:
A control which occurs through repressor is known as negative control which may be inducible or repressible.
When a small molecule named as allolactose binds this repressor it leads to allosteric repulsion which removes repressor from the operator as a result of which RNA polymerase can start transcription. Allolactose is therefore known as inducer because it induces lac operon expression.
But here, the operator is active (induced) already so there is no need to induce the operon which means that it can only be repressed so that transcription could stop. So the answer is negatively repressible operon.
Answer:
fills container, no visible shape, flows
Answer:
This question is incomplete, the options are:
A. Two copies of the allele that determines phenotype whenever the allele is present
B. Two copies of the allele whose effect is hidden unless the other allele is absent
C. One copy of the allele that determines phenotype when present and one copy of the other allele
D. One copy of each of two alleles that both contribute equally to determining phenotype
The answer is B.
Explanation:
According to Gregor Mendel, a Gene comes in two alternative forms called ALLELES. One allele called the DOMINANT ALLELE is capable of masking the phenotypic expression of the other called the RECESSIVE ALLELE. The dominant allele will always express itself whenever it is present. However, a recessive trait will only be expressed when two alleles for recessiveness occur in the gene.
An individual whose genotype is for the recessive allele will have two copies of the allele whose effect is hidden unless the other allele is absent. This means that in that particular gene, the two present alleles will be recessive alleles.
