Answer:
In an ecosystem, energy enters in the form of solar energy or light energy from sun. Solar energy is transformed into various other types of energies like kinetic energy, chemical energy, potential energy, etc; but it eventually leaves the ecosystem in the form of heat energy.
39
Reproductive cells are haploid (have 1/2 the chromosomes), whereas somatic/body cells are diploid (have the full set of chromosomes)
This makes sense if you think about it. Using the example from the question, every dog has 78 chromosomes. This includes two of each (there are two chromosome 1's, two chromosome 2's, etc. This is visible in the karyotype attached). One set of these chromosomes were inherited from the mother, and one set from the father. Each parent contributed 39 chromosomes (one chromosome 1, one chromosome 2, etc.). If the dog in the question were to have 78 chromosomes in its sperm cells, it would contribute two sets to its offspring. When combined with the chromosomes in the egg cell, the offspring would end up with extra chromosomes. Therefore, both the sperm and the egg cells will have 39 chromosomes, one of each. When combined, they will produce offspring with 78 chromosomes, the proper number.
Normally it’s the plasmodesmata that allows exchange of molecules between adjacent cells. But I’m still not sure if water is included!
Answer
Just think critically about why (if you were an egg laying species), having a fetus/baby develop inside of you would be advantageous.
For one, eggs are much less protected from outside factors such as predators, temperature, etc than live birthed creatures. Live birth provides protection inside the mothers body from things such as heat, cold, moisture, predatory animals, etc. An egg laying animal must keep its eggs at a perfect temperature and check to make sure no other animal has eaten them.
False, a lipid bilayer is a MOSTLY apolar cell structure,which means polar molecules can't easily go through it