Answer:
The correct answer will be option-A
Explanation:
Desert biomes are characterised by the presence of the arid conditions or with few or less amount of rainfall.
The plant groups called the bryophytes and pteridophytes are dependent on the water for their fertilization which allows completing their life cycle.
In the desert conditions provided in the question, the mosses and ferns survived for many generations as these plant groups produced sperms with flagella which helped the sperms to swim in the water provided by the 10-inch rainfall per year and reach the female gamete and fertilize the egg cell.
Thus, option-A is the correct answer.
Answer:True
Explanation:
Nerve impulse must reach a certain threshold in a neuron before action potential can be generated to intiate conduction of action potential.
Therefore if mutiple impulses are generated and these are not upto thresholds , no matter how strong the stimulI are-NO ACTION POTENTIAL WILL BE GENERATED.
THIS IS ALL OR NONE PRINCIPLE
The all or none hypotheses can be best explain with flushing of the water closet after using it. If required volume of water is not pumped into the water closet storage above, no matter how long the handle is push, FLUSHING WILL NOT TAKE PLACE.Thus the threshold volume of water must be met.
The answer is 49.92%
Let's use the <span>Hardy-Weinberg principle:
p + q = 1
p</span>² + 2pq + q² = 1
<span>
where:
p - the frequency of dominant allele G
q - </span>the frequency of recessive allele g
p² - the frequency of homozygous dominant individuals GG with colour green
2pq - the frequency of heterozygous individuals Gg with colour green
p² - the frequency of homozygous recessive individuals gg with color brown
23% of the population is brown: p² = 23% = 0.23
p = √(p²) = √0.23 = 0.48
p = 0.48
p + q = 1
0.48 + q = 1
q = 1 - 0.48 = 0.52
<span>The percentage of the population that is expected to be heterozygous is 2pq:
2pq = 2 * p * q = 2 * 0.48 * 0.52 = 0.4992 = 49.92%</span>
Answer:
I would expect that the sample has only 50% of the original 235 U.
Explanation:
That is because 235 U has a half-life of 700 million years and I expect that my sample be 350 million years old. 350 is half of 700.
Answer:
The first male was bb Ee, and the second male was bb EE.
Explanation:
In Labradors coat colour is controlled by two genes. Suppose the two genes are B and E. B produces black colour and recessive form bb gives brown colour. Gene E is epistatic over gene B in its recessive form which means that ee will produce yellow colour regardless of the genotype present of B gene.
The first case is possible if the female lab is bbee (yellow) and the male lab is bbEe (brown):
bbee X bbEe
bE be
be bbEe bbee
So half of the offspring will be brown (bbEe) and half of them will be yellow (bbee)
The second case is possible if the same female bbee mates with a brown male of different genotype which can be bbEE:
bbee X bbEE
bE
be bbEe
So all offspring will be brown (bbEe)
Hence, the first male was bbEe and the second male was bbEE.
