<span>Flatworms use a system of canals and tubes with the mouth as their excretory organ. They belong to the Phylum Platyheminthes. </span><span>Flatworms
can be cut in half creating two individuals by binary fission. Binary
fission is a type of asexual reproduction in which the offspring has the same
features and characteristics of the parent. During binary fission, the DNA
replicates into two and goes at the end of each membrane. And then the cell
membrane divides into two daughter cells. Then cytokinesis follow.</span>
Transcription occurs in the nucleus of the cell. RNA polymerase breaks the hydrogen bonds and unzips a portion of DNA. RNA nucleotides match the DNA strand forming mRNA. In mRNA thymine is replaced by uracil. Once mRNA is formed it leaves the nucleus through a nuclear pore into the cytoplasm. The purpose of mRNA is to remove the protein code out of the nucleus without pulling the DNA out. mRNA then needs to find ribosomes in the cytoplasm which can be found on the rough ER. mRNA has read three bases at the same time and these are called codons. Ribosomes read the mRNA code and add the correct amino acid using tRNA. tRNA has an anti-codon on one end which will match a specific codon, and a specific amino acid on the other end. This will make translation happen.
Translation- mRNA attaches to a ribosome and a start codon must be read. tRNA brings the first amino acid which matches the codon on mRNA. The next tRNA molecule moves in and matches with the codon on mRNA while amino acids form a peptide bond. First tRNA detaches itself and mRNA shifts for the next tRNA molecule to come in. Protein grows until a stop codon is reached and then it's ready to finish folding to become functional.
Some _club____ fungi can be eaten, but there are also some that are harmful to plant life, like wheat rust. club sac zygote-forming chytrid imperfect