ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Biology => Topic started by: dreambig on January 21, 2013, 10:01:21 pm
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Just a general question that has been bugging me about ribosomes:
If they are not membrane bound what keeps ribosomes in shape?
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Through covalent bonds. Ribosomes are rRNA (ribosomal ribonucleic acid) - they maintain their structure much the same way that any other RNA strand does.
EDIT: Forgot to mention that the ribosome consists of both rRNA complexes and proteins - it is a ribonucleoprotein.
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EDIT: Forgot to mention that the ribosome consists of both rRNA complexes and proteins - it is a ribonucleoprotein.
Hence, a conjugated protein :)
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Hence, a conjugated protein :)
I wouldn't classify a ribosome as a conjugated protein, seeing as its structure is primarily ribonucleic acid-based.
Haemoglobin is a conjugated protein, in that it is primarily a protein in structure but has heme groups. Following the definition of a conjugated protein, it can only be a protein that functions in conjugation with other chemical groups.
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I wouldn't classify a ribosome as a conjugated protein, seeing as its structure is primarily ribonucleic acid-based.
Haemoglobin is a conjugated protein, in that it is primarily a protein in structure but has heme groups. Following the definition of a conjugated protein, it can only be a protein that functions in conjugation with other chemical groups.
Yeah I guess that's valid. So really I think knowing that ribosomes are made primarily of RNA (rRNA) would be important, and knowing that ribosomes remain compact because of the bonds between the RNA nucleotides! :D
^ It is probably a segment of learning about the 3 types of RNA:
a)mRNA (messenger RNA)
b)tRNA (transfer RNA)
c)rRNA (ribosomal RNA).
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Just something handy to remember when you're looking at protein synthesis. The context of a SAC/exam question would lead you to making an accurate judgement as to where a particular protein is actually synthesised. The formal way VCAA actually wants your response to be is the following:
* Any proteins synthesised within a cell and are utilised within the intracellular environment (e.g. lysozame for intracellular digestion is lysosomes), are said to be synthesised in free ribosomes.
*Any proteins that are synthesised and then secreted outside the cell into the extracellular environment of a cell (e.g. insulin hormone for blood glucose regulation), are said to be synthesised in the Rough Endoplasmic Reticulum.
:) Just a handy insight. Also, make sure you never write ER.. always say Endoplasmic Reticulum, because ER is not universally recognised as meaning Endoplasmic Reticulum.