Cells & Organelles

What are the main ideas of the cell theory? Select 2.

What are the advantages of using light microscopes? Select all that apply.

What are the disadvantages of using electron microscopes?

Diffusion is efficient at < [blank_start]50[blank_end] um. As cells increase in size, [blank_start]volume[blank_end] increases more than [blank_start]surface area[blank_end]. The distance from the [blank_start]nucleus[blank_end] to the [blank_start]periphery[blank_end] influences the rate of movement of intermediates, waste products etc. Thus, cells must be [blank_start]small[blank_end] to ensure this movement is efficient.

Which component of the cell removes diffusion as the transport mechanism to overcome size limitation?

Check all the features of a eukaryotic cell

Viruses can only replicate using the protein synthesis mechanisms of host cells

The nucleus is surrounded by a double membrane called the [blank_start]nuclear envelope[blank_end] which surrounds the internal [blank_start]nucleoplasm[blank_end] environment. [blank_start]Nuclear pores[blank_end] allow entry and exit of materials such as mRNA. The nucleus retains genetic information in the form of [blank_start]chromatin[blank_end].

Check the processes that occur in the smooth endoplasmic reticulum

A xenobiotic is a chemical product in an organism that would be expected to be present there

What is the name of the folds formed by the inner membrane of the mitochondria?

A peroxisome is a [blank_start]membrane-bound[blank_end] sac found in the [blank_start]cytosol[blank_end] containing [blank_start]enzymes[blank_end] which carry out [blank_start]oxidation[blank_end] of VLCFA and amino acids to [blank_start]hydrogen peroxide[blank_end]. It has [blank_start]low[blank_end] electron density.

When peroxisomes [blank_start]oxidise[blank_end] VLCFA and amino acids to [blank_start]hydrogen peroxide[blank_end], the hydrogen peroxide must be removed because it is [blank_start]toxic[blank_end]. Thus, peroxisomes also contain [blank_start]catalase[blank_end] enzymes. These enzymes convert hydrogen peroxide to [blank_start]oxygen[blank_end] and water. This ensures safe [blank_start]oxidative metabolism[blank_end].

What is a plasmalogen?

What is glycosylation?

Zellweger syndrome is characterised by a lack of what?

Infants with Zellweger syndrome usually do not live past 1 year and have facial deformity, intellectual disability as well as impaired vision and hearing. What causses this?