Viruses and cell cycle Flashcards
What’s meant by lysogenic pathway?
When DNA viruses insert their DNA into a host DNA so it gets replicated every time the host cell divides.
What’s a provirus?
When they insert their DNA into host DNA
What’s the lytic pathway?
The genetic material is replicated independently of the host DNA straight after entering, mature viruses are made and the host cell bursts.
Is lysogenic virulent or non-virulent?
What about lytic?
Non-virulent.
Virulent.
What causes the cell to burst when viruses enter?
Enzyme lysozyme is synthesised and released
What are some ways to control disease? (3)
Prevent transmission (hand washing), rapid identification, sterilisting equipemtn.
What are nucleosomes?
Lots of strands of DNA wound around the histones, making up part of a chromosome.
What is a karyotype?
A display of all the chromosomes of the cell
What is interphase?
Period of non-division where cells increase in mass and size, carry out normal cellular activities and replicate DNA.
What happens during prophase in mitosis?
Chromosomes coil up and become visile - two daughter chromatids. Nucleolus breaks down and centrioles pull apart to form spindle.
What happens in metaphase in mitosis?
Centrioles have moved to opposite poles forming microtubules between them, the SPINDLE. The chromatids line up along the equator with each centromere associated with a spindle microtubule.
What happens in anaphase in mitosis?
The centromeres split and the chromatids from each pair are drawn towards opposite poles by microtubules.
What happens in telophase in mitosis?
The spindle fibres break down and nuclear envelopes form around two sets of chromosomes. The nucleoli and centrioles reform. Chromosomes begin to unravel and become less dense.
What happens in cytokinesis in animals in mitosis?
A ring of contractile fibres tightens around the cell centre until the two cells separate.
What happens in cytokinesis in plants in mitosis?
Celllose cell wall builds up from inside of cell outwards, separating them.
