Answer: the tails are hydrophobic and the heads are hydrophilic
The correct answer is d. 3.5 billion years.
Prokaryotes were the first forms of life on Earth long before simple multicellular life appeared because of their ability to withstand extreme conditions. It is believed that the first living forms were bacteria combined with archaea in the microbial mat (multi-layered sheet).
The answers would be:
Genotype Phenotype
Tt Tall stemmed
tt Short stemmed
Genotypic ratio : 2:2 or 1:1
Phenotypic ratio: 2:2 or 1:1
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<u>You can read on to see how this was done:</u>
Tall stems (T) are dominant to short stems (t).
First figure out the genotypes of the parents. We have a short-stemmed plant and a heterozygous long-stemmed plant cross.
For short stem to occur, you need 2 pairs of short alleles. So the first parent would have a genotype of tt.
Heterozygous long-stemmed means that the parent has one of each allele. So the genotype of the second parent would be, Tt.
Now we can make our Punnett Square.
tt x Tt
<u> t t </u>
<u>T | Tt | Tt</u>
<u>t | tt | tt</u>
Let's list down the genotypes and phenotypic results.
Genotype no. Phenotype
Tt 2 Tall stemmed
tt 2 Short stemmed
So from that we can answer the other questions:
Genotypic ratio : 2:2 or 1:1
Phenotypic ratio: 2:2 or 1:1
Dendrites is 1
Soma is 2
Nylon sheeth is 3
Node of Ranvier is 4
Synapse is 5