Chromosomes are thread-like structures in which DNA is tightly packaged within the nucleus.
Mussels are molluscans and are freshwater animals. The change in the environment led to new traits of mussels, it underwent natural selection and the thick shells have high chances of survival.
<h3>What is natural selection?</h3>
Natural selection is a process of nature that eliminates the organism with less survival and unfit traits while selecting the organisms with better traits of survival in the altered conditions.
The arrival or the introduction of the crabs in the environment altered the previous habitat of the mussels and led to the adaptation of the better trait quality in the mussel species.
The trait of the thick shells underwent natural selection as they were favoured for the changed conditions. The mussel having thick shells have high chances of survival over thin-shelled mussels as the crab will find it hard to attack the thick-shelled mussels.
Therefore, option A. change in environment, option B. natural selection and option E. chances of survival are the correct statements.
Learn more about the natural selection here:
brainly.com/question/10715606
Summer
, for the northern hemisphere, summer is the warmest time of year. It's not because the planet is that much closer to the Sun, it's because the top part of the Earth is facing the Sun for a amount of time.
The Sun is directly over the Equator during the autumnal equinox, and heating the northern and southern hemispheres equally. As the northern hemisphere is moving towards shorter days and the cold winter, the southern hemisphere is watching the snows melt and the flowers bloom during their spring.
Summer is the season where the Earth is tilted way from the Sun and the South Pole is getting all of the light
Spring is a bit of a mirror image to our position in autumn. The Sun is directly over the Equator during the equinox and the northern and southern hemispheres
What’s is the cart to this problem?
The pentose sugar on RNA is called ribose. (a trick to remember it is that the "R" in RNA stands for ribo)
Hope this helps :)
