Bio-Plants, Bacteria Etc..

ESSAY QUESTIONS FOR EXAM 2: BIO 104

3. Epithelial tissues covers body surfaces and lines the body cavities its functions include lining, protecting, and forming glands. Functions: contains cilia which aids in movement of substances; secretion and lubrication; absorption, transportation, sensory, boundary and protection. Can be categorized in two groups, simple epithelium (sub-division 5 groups; cuboidal, squamous, columnar), stratified epithelium and pseudostratified.

LONG ESSAY QUESTION:

1. It is widely accepted that eukaryotes evolved from Achaea, not Bacteria. List three pieces of

Evidence that support this and briefly explain each one.

* Achaea Are prokaryotes but they have some characteristics of Eukaryotes such as some introns an mRNA splicing, they wrap their DNA in histones to form nucleosomes and chromatin, and some have linear chromosomes.

* Bacteria do not have introns during mRNA splicing like eukaryotes which have introns and exons. Introns are the DNA base pairs with their corresponding RNA pairs that are spliced out to make mature RNA.

* Bacteria do not wrap their DNA in histones because they don’t produce them and they also do not have any chromatin. Histones are protein that wraps the DNA in eukaryotic nuclei and they package and order DNA into structural units called nucleosomes which are chief components in chromatin.

* Bacteria only have circular chromosomes. Eukaryotes have linear DNA that initiates replication and multiple origins.

2. Please list and explain four major innovations to the animal body plan that emerged during the

Evolutionary history of animals. For each one, also indicate the/a clade of animals that

Possesses the innovation, and an example organism, and a clade and an example that does not

Possess it.

* The first innovation or grade is the evolution of tissues which is the group of specialized cells working together for one specific function. Animals with true tissues are called...