Crossing over occurs at the four-strand stage when two homologous chromosomes, each consisting of a pair of sister chromatids, are paired. Each crossover involves just two of the four strands and generates two recombinant strands.
Hope this helps!
Living things breath, feel, and smell.
Most living things have those characteristics.
I’m not 100% sure, but I hope I helped a bit.
Answer:
- inheritable changes
- genetic
- generations
I don't know about the second sentence, is it possible you give me a bit more of a context then maybe i can be of help
Answer:
Because the English measurement system has been in use for a very long time, it will be costly and time consuming to change from the English to SI units. Many technological measurements, products, and tools were developed in English units.
The cost of converting all measurements to SI units will be costly and will require a long period of time. Conversions between the English and the SI system of units appear to be more cost-effective than hardware changes.
Example:
It will be costly to convert designs for bridges, tunnels, locomotives, automobiles, and other hardware to the SI system. Although new designs are being performed in SI units, much useful hardware based on English units still remain.
Eventually, it is likely that complete conversion from English to SI units will happen, albeit slowly.