Bio topic 2 Cells questions

Explain function of ATP hydrolase

ATP to ADP+ Pi releases energy

Allows ions to be moved against concentration gradient

Movement of Na out of cell slows absorption of glucose into cell lining the ileum. Explain how

Generates concentration gradient for Na+ from ileum to cell

Na moving in by facilitated diffusion brings glucose wit it

features you would expect in a cell specialised for absorption

1. Folded membrane so large surface area

2. Large number of carrier or Channel proteins

3. Large number of mitochondria for more ATP

4. Membrane bound digestive enzymes so maintains concentration gradient.

Explain advantages of lipid droplet and Michelle formation

Lipid droplet increases surface area for enzyme action so faster hydrolysis

Micelles carry fatty acids and glycerol through membrane to epithelial cell.

How is Golgi involved in absorption of lipids

Modifies triglycerides

Combines them with protein

Packaged for release / exocytosis

How is a virus now able to infect other species

Mutation in viral DNA/RNA

Altered tertiary structure of viral attachment protein

Name 2 techniques used to analyse viral DNA to determine viruses are related

Polymerase chain reaction

Genetic/DNA fingerprinting

DNA sequencing

Determining genome of viruses allows scientists to develop vaccine how?

Could identify the protein from genetic code

Then identify the antigen to use in vaccine

What is monoclonal antibody

Antibody with same tertiary structure

Describe role of antibodies in producing a positive result in ELISA test

First antibody attaches to antigen

Second antibody with an enzyme attaches to antigen

Substrate added and colour changes

How does HIV replicate

Attachment proteins attach to receptors on T cell

RNA enters cell

Reverse transcriptase converts RNA to DNA

Viral protein produced

Virus particles assembled and released from cell

How is HIV replicated once inside helper T cell

RNA converted to DNA using reverse transcriptase converts

DNA inserted into helper T cell DNA

DNA transcribed into RNA

HIV mRNA translated into viral proteins for assembly into viral particles