Evolution of Diversity. Two of the major transitions that occurred in the evolution of life on earth, long before any plants or animals were around, involved the evolution of cyanobacteria and later the first eukaryotic organisms.

(A) Approximately when did the first cyanobacteria evolve, and what made them so different from earlier photoautotrophs? Describe at least TWO ways that cyanobacteria changed the physical conditions on Earth and eventually paved the way for the evolution of other organisms.

Describe the series of events that occurs during an action potential, including the ions involved, how each ion is moved, and the change in membrane potentials.

• Explain the role of myelin in conduction of action potentials.

• Explain how neurotransmitters transmit signals across synapses.

• Distinguish between sensation and perception.

• Describe the function of sensory receptors and list 5 types. •

1. Describe the 3 levels of defense mechanisms.
2. Describe the importance of mast cells, complementary proteins and phagocytes in inflammatory response.
3. Why is the lymphatic system important for the immune system?

Please, type the answers

What is the difference between tan1 mutants in maize and tan1 mutants in Arabidopsis? Why must a tan1, air9 double mutant be used in Arabidopsis? Be sure to define double-mutant (synthetic mutant)

You want to use PCR to amplify a 1Kb exon of the human autosomal gene phenylalanine hydroxylase (PH) from the genome of a person suffering from the disease phenylketonuria, which is due to this enzyme not functioning.

a) You start with 1 nanogram of genomic DNA in your sample tube. Assuming a human haploid genome is 3 x 10⁹ bp, and each bp has a mass of 660 g/mole, how many moles of haploid genomes are present at the start of your PCR experiment?

b) The PH gene is present in a single copy in the haploid genome. How many template molecules of the PH gene are present at the start of your PCR experiment? (Give your answer in molecules, not moles of molecules.)

c) You set your PCR machine to run for 25 cycles to amplify your 1 kb fragment. Assume every cycle exactly doubles your desired target DNA. At the end of your 25 cycles, how much amplified DNA have you created, in terms of number of molecules AND mass of DNA?

What is p53? Why do so many different types of cancer involve p53? What happens to a cell that is carrying damaged DNA if both of its TP53 alleles become inactivated? What are the various functions of P53?

What problems, in terms of wavelength sensitivity, explain colour blindness?

Stereoscopic vision is necessary to tell whether a body is rotating or just changing shape.

a. Explain why the right eye needs the input from the left eye to distinguish between the different paths from A to A1- A2.

Explain how awareness is created among schools and other organizations about public health. Provide examples

1.Suppose the codon is UUA, what is the anticodon?  

2.What is tRNA? Why is it important?  

explain the role of stress in the development of psoriasis.

6. What evidence (data/graphs) from the example of marine iguanas (Ch. 11) demonstrates sexual dimorphism and what data or graphs demonstrate the difference between sexual and natural selection on females and males?

The future challenges that demand continuous collaboration in the world public health sector:

Explain:

Reduce treatment and drug costs in the future.
The increase of natural disasters and outbreaks of diseases.
The threat of bioterrorism.

GATA family of transcription factors are important regulators of cell identity. The family member GATA1 is required for the switch from an immature erythroid cell into a mature red blood cell. As part of this switch, GATA1 binds to the consensus DNA sequence GATAAA through interactions with the DNA major groove. One of the results is the massive upregulation of globin mRNA.

Design a set of experiments to demonstrate that GATA1 binds to GATAAA containing sequences and does so through major groove recognition/binding mechanisms.