Answer:
1. Cell wall/Cell membrane
2. Cytoplasm
3. Ribosomes
Karyotype is written in the form: No. of chromosomes, sex chromosomes
As, we know there are 46 chromosomes in humans & sex chromosomes may be XX for females & 'XY' for males so, we can write it as:
(46, XX) or (46, XY)
There could be some anomalies though. So, for more appropriate answer, you should put your options!
Hope this helps! Pm me in case of doubt! Happy Studying :)
Answer: Option 'd' is correct.
Explanation:
Since we have given that
Number of fish caught = 100
Number of tagged fish in catch = 24
So, total number of the fish in the pond is given by
Number of fish caught + Number of tagged fish in catch
=100 +24
= 124
So, the best estimate to find the number of fish in the pond is 124.
Hence, Option 'd' is correct.
The winter solstice is the shortest day of the year. The sun is at its lowest point in the sky during this day. At 66 degrees latitude, the tilt of the Earth causes the sun to look like it is standing still in the sky, because it has reached its lowest point in relation to Earth's tilt.
Answer:
Post reproductive isolation → Hybrid sterility
Explanation:
The biological concept of species states that individuals of a species can not mate and reproduce with individuals of another species. But if they get to reproduce, the progeny will not be viable or fertile. There will not be any reproductive success.
There are different reproductive isolation mechanisms, which are barriers that inhibit or interrupt the genetic flow between different species.
Reproductive barriers are isolation mechanisms that prevent mating between two or more species. The prezygotic mechanism avoids fertilization between individuals of different species, while the postzygotic mechanism impedes the zygote to develop and reach the adult stage.
Postzygotic mechanisms or barriers include
- Hybrid inviability,
- Hybrid sterility,
- Hybrid decreased viability or fertility,
- Cytoplasmic interactions.
In the exposed example, it seems that the mountains separating the frogs´ populations made a place for the development of postzygotic barriers, specifically hybrid sterility. Frogs from one population get to mate and produce offspring with the frogs of the other population, but their progeny is sterile.