Question

Answer questions in regards to Botany;

Infer a phylogeny when provided with a simple character matrix. Be prepared to interpret evolutionary relationships based on a phylogeny.

How does molecular data inform phylogenetic analysis?

Distinguish among the three domains. Which two domains are most closely related to each other?

How does our current understanding of the evolutionary relationships among eukaryotes differ from the four-kingdom system?

Answer 1

1. - Molecular data helps us to draw the relationship betweenDNA sequences by making comparisons among these sequences , thus this technique is called molecular phylogenetics. Nutall's work showed us that molecular data can be used in phylogenetics.When molecular data are used a single experiment can provide information on many characters in a DNA sequence. For example, position of each nucleotide in the DNA sequence (A, C,T, G). Protein electrophoresis is one such example of molecular data. DNA Hybridization for comparing two organisms.

2- Organisms can be classified into three domainsbase on the differences in their nucleotide sequence in RNA, cell membrane structure and sensitivity to antibiotics. Three domains are Archaea, Bacteria and Eukarya.

Archaea- They are prokaryotic cells. Cell walls do not contain peptidoglygan. They live in extreme environments. Examples- methanogens, hyperthermophiles, halophiles

Bacteria- They are known as eu-bacteria. They are also prokaryotic cells. Cells walls of Vacteria contain peptidoglycan. They can be found almost everywhere. Examples- mycoplasmas, cynobacteria, Gram +,- bacterias

Eukarya- They have eukaryotic cells. Not all eukarya have cell walls but those having cell walls have no peptidoglycan. Examples - Fungi , yeast, mosses, flowering plants etc.

**Archaea and Eukarya are most closely related to each other as Archaea have genes and other metabolic pathways thar are more similar or close to eukaryotes, for example, enzymes used in transcription and translation process.