Answer:
9:3:3:1
Explanation:
If two parents for a dihybrid cross are fully heterozygous for two genes, the phenotype ratio comes 9:3:3:1. Here, the alleles of both genes should exhibit complete dominance-recessiveness. This means that one allele of a gene should be able to mask the expression of its another allele. Similarly, alleles of one gene genes should assort in a random manner during anaphase-I irrespective of the assortment of alleles of another gene.
Under these conditions, each parent produces four types of gametes in equal proportion. And the random fusion of these gametes gives progeny in 9:3:3:1 phenotype ratio.
For example, a dihybrid cross between TtRr and TtRr would produce progeny in the following phenotype ratio=
9 tall and red: 3 tall and white: 3 dwarf and red: 1 dwarf and white
Here the allele T gives "tallness" while the allele "t" gives "dwarfism". The dominant allele "R" gives "red flowers" while the recessive allele "r" gives white flowers.
The correct answer is - A) Swamps tend to be humid while deserts tend to be dry.
The swamps are places that are dominated by shallow, murky waters. The precipitation at these places is relatively high, and the climate tends to be pretty stable throughout the year, being relatively warm. Because of the precipitation, the water surface, and the temperatures, the swamps tend to be very humid places.
The deserts are the total opposite. They are dry all year round, with maybe one or two days in the year where precipitation will occur, though occasionally that may be once every several years. Depending on the type of desert, the climate is either very hot all year and very dry, or very hot in the summer and very cold in the winter and dry.
Answer:
c. the height of radish seedlings is measured
Explanation:
Quantitative measurements revolve around the quantity of things and exact measurements. The measured height of a radish seedling is the perfect example of that.
Memory technique:
- <u>Quantit</u>ative observations involve <u>quantit</u>y (numbers).
- <u>Qualit</u>ative observations involve <u>qualit</u>y (descriptions, features, i.e. color, smell, shape)
Answer:
The correct answer is - Control microcosms did not contain living moss, while experimental microcosms did contain living moss.
Explanation:
The difference between the control microcosms and experiment Microcosms is, the presence of the living moss in the experimental group whereas the control group does not contain living moss.
The independent variable in this research setting is the presence or absence of the living moss and for the control group, the mosses are filtered out and only added the water.
