Answer:
1/4 or 1/2 depending on mating partner of F2
Explanation:
Assuming that the F1 parent Rr mated with a plant with the RR, Rr or rr genotype the F2 offspring would have the following genotypes:
Rr x RR= 1/2 RR, 1/2 Rr
Rr x Rr = 1/4 RR, 1/2 Rr, 1/4 rr
Rr x rr = 1/2 Rr, 1/2 rr
The F2 generation with the RR genotype could not be the parents of the F3 generation because to have individuals with the rr genotype the F2 generation would have to mate with a plant that is either Rr or rr in which case the fraction of the population with the stripe rust phenotype will either be 1/4 or 1/2, respectively.
I think it is a structure of:dim is light where the radial muscles of the iris contract
Circular muscles of the iris relax
Pupil dialates
More light enter the pupil
Answer:Environmental pollution is any discharge of material or energy into water, land, or air that causes or may cause acute (short-term) or chronic (long-term) detriment to the Earth's ecological balance or that lowers the quality of life. Pollutants may cause primary damage, with direct identifiable impact on the environment, or secondary damage in the form of minor perturbations in the delicate balance of the biological food web that are detectable only over long time periods.
Air pollution is the process which the substances and the energy forms are not present in normal atmospheric composition reach the atmosphere, or are present but in much lower concentrations.Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or cause damage to the natural environment or built environment, into the atmosphere.
More than 3,000 substances that are not part of the atmospheric composition, falling in the atmosphere can be considered air pollutants.
Some substances that are normally present in the atmosphere in a certain concentration can be considerate pollutants because their concentration is much higher than usual concentration.
Also certain substances that are normally present in certain layers of the atmosphere (e.g. ozone in the stratosphere), once arrived in the troposphere is pollutant.
Some gases, such as oxides of nitrogen may have beneficial effect on vegetation, after hydration may affect the leaf fertilizer.
The air pollutants factors can be chemical (chemicals), mechanics (particles in suspension) physical (ionizing radiation) and acoustic (noise).
Explanation:if this helped mark me brainliest
Just So you know, <span>The molecular clock, explains Blair Hedges, is a tool used to calculate the timing of evolutionary events. Instead of measuring seconds, minutes and hours, the molecular clock measures the number of changes.</span>
Answer: Insects create the biological foundation for all terrestrial ecosystems. They cycle nutrients, pollinate plants, disperse seeds, maintain soil structure and fertility, control populations of other organisms, and provide a major food source for other taxa
Facts about insects: Insects are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body, three pairs of jointed legs, compound eyes and one pair of antennae.
