Answer:
Mechanisms enabling one cell to influence the behavior of another almost certainly existed in the world of unicellular organisms long before multicellular organisms appeared on Earth. Evidence comes from studies of present-day unicellular eucaryotes such as yeasts. Although these cells normally lead independent lives, they can communicate and influence one another's behavior in preparation for sexual mating. In the budding yeast Saccharomyces cerevisiae, for example, when a haploid individual is ready to mate, it secretes a peptide mating factor that signals cells of the opposite mating type to stop proliferating and prepare to mate (Figure 15-2). The subsequent fusion of two haploid cells of opposite mating types produces a diploid cell, which can then undergo meiosis and sporulate, generating haploid cells with new assortments of genes.
Explanation:
Brainliest please?
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.
Answer:
In an ecosystem, energy enters in the form of solar energy or light energy from sun. Solar energy is transformed into various other types of energies like kinetic energy, chemical energy, potential energy, etc; but it eventually leaves the ecosystem in the form of heat energy.
Answer:
cell wall, chloroplast, and one big vacuole
Explanation:
Cell wall - exterior to the cell membrane is a rigid cell wall made up of cellulose. It is freely permeable to water and solutes but prevents the cell from bursting
Chloroplast- contains green pigment, chlorophyll, which traps light used in photosynthesis.
Vacuole- filled with sap which contains sugar, salts and waste products and enclosed by tonoplast. Acts as a store for sugars and salts. Maintains the shape of the cell.
