Question
It's just a bit confusing for me on figure.1
1. When you put HeLa cells in hypotonic buffer, how can you get nuclei? is that because water is getting into the HeLa cell and nuclei getting out?
2. then also when you put nuclei in hypertonic buffer, it says soluble protein will be extracted, is that because when you put nuclei in hypertonic solution, water will be taken, so soluble protein will be taken?
Lab 1: Structure of DNA Lab 1: Structure of DNA - Part I fve carbon SAr Phosphote gvap Introduction 2'-Deoxyribonucleic acid (DNA) is composed of repeating subunits called nucleotides. Each nucleotide consists of a five-carbon sugar, a phosphate group, and a nitrogenous base (either adenine, thymine, cytosine, or guanine),. Structurally, DNA is an antiparallel double-helix with the individual strands held together by the pairing of complementary bases between the two strands (2, 3). The jnegatively charged phosphate groups of each nucleotide are on the outside of the helix giving the DNA molecule its acidic character (4, 5 In vivo, DNA is arranged in the context of chromatin a term referring to the s packaged nature of "free DNA" with histone octamers (Figure 1). The histone octamer pnir contains two molecules each of H2A, H2B, H3 and H4. Approximately 150 base pairs (bp) of DNA is wrapped around each histone octamer 1.7 times. This structural unit of chromatin is called a nucleosome (two nucleosomes are shown above). If the H1 protein associates with a nucleosome it is now referred to as a chromatosome Chromatosomes compact the genome more than nucleosomes and are associated with 166 bp of DNA (Figure 2) (8, 9) Metaphase Figure 1. The Hierarchy of DN Structure Double stranded DNA is arranged in varying levels of compacti vivo, ranging from the naked DNA fiber to the fully compacted Chromosome 2 nm DNA 30 nm Chromatin Fiber CRn in vo metaphase chromosome Nucleosomes provide the material on which DNA is wrapped, and the Certvica repetitive unit by which the genome // cancer is ultimately arranged (8, 9). ? 11 nm Nucleosome akes DNA The starting material for e this lab is 01% NP 40 treated nuclei from HeLa cells HeLa cels were incubated in a hypotonic buffey and the nuclei were colected and washed Incubation in a hypertonic buffer extracted the soluble proteins from the nuclei; this produced a nuclear extract that can be used int in vitro transcription assays, as well as other experiments that utilize nuclear proteins. The remaining extracted nuclei now only Co contain those proteins tightly bound to DNA -namely, the components of chromatiq AR 54 ALINH Hela Hypfonic
Explanation / Answer
1.)Yes it is because water is entering into the cell which causes bursting of cell and nucleas is released from cell as when a cell is placed in an hypotonic solution endosmosis takes place which causes bursting of cell and release of cell material.
2)Yes it is so.Because when a cell is placed in hypertonic solution exosmosis takes place.
