Everything In Bio Flashcards
What is the molecular amino acid building blocks?
The four elements to an amino acids is an amino group (NH2), an carboxyl group (COOH), then a hydrogen connected to a center carbon and last an R-chain, each specific to the 20 different amino acids.
How many essential amino acids are there out of the 20 that we use in making proteins?
There are 9 essential amino acids that the body does not make, and ergo there is 11 non essential
What is the promotor of a gene?
The promotor of a gene is where the transcription will start copying in terms of transcription. Ahead of all genes there is an area on the DNA that says where the transcription will start. This is the area that is called the promotor
What is the enzyme complex RNA-polymerase? And what jobs does it got?
The enzyme complex RNA-polymerase is an important protein complex that have a very important role in making protein. The jobs that it’s involved with is first that one of the enzymes hooks on to the promotor, it does this with help of transcription factors that identify and latch on to the promotor.
RNA polymerase also separates the DNA. Then another RNA polymerase can come and make an mRNA-thread
mRNA is made as the complementary unit of the DNA strand it gets copied from, but which end does the DNA strand start from, and then which end does the mRNA start with?
Since we got two ends, one 3’ end and one 5’ end, that start in each corner, and since DNA gets transcripted from the 3 to 5 end, then the mRNA goes from 5 to 3 end.
How fast does RNA-polymerase make nucleotides?
It makes around 50 nucleotides per second. Which is kinda intense
What is an intron, an exon and spliceosome?
A gene contains the recipe for the protein, but inside that gene there is areas that do code for the protein (exon(express)) and then there are areas that fills in the gap between (intron). In order to make the finished protein the areas that do not code needs to get eliminated. This is where spliceosome comes in. Spliceosome comes in and cuts open the pre-mRNA (the first mRNA) and cuts out the intros, leaving only the expressed gene left, the exons, which then is the finished mRNA.
The first part of modifying the pre-mRNA is where the 5’ and 3’ ends gets attachments, what happens?
In the 5’end enzymes comes and give it a phosphate group, this group is called the 5’cap. And in the 3’end it gets a tail of nucleotides with the base adenin, this tail is called the 3’poly-A. These modifications will protect the ends of the mRNA in cytosol in the process of translation, also it helps the ribosome connects properly to the mRNA
What is start kodon?
After the sub unit of the ribosome locks on the 5’cap, then it rolls on the mRNA until it finds the start kodon, which is the nucleotides AUG. Here it can start the protein synthesis and locate the complemtary tRNA’s. AUG is the antikodon UAC, which is tRNA(met) the amino acid mentionin
What is a stop kodon?
A stop kodon is the place on the mRNA that lets the ribosome know that the protein synthesis is complete. It’s one of three stop kodon; UAA, UAG or UGA, these do not have an anti kodon to match, instead a protein called a stop factor connects to the stopkodon and the whole ribosome complex detached from itself.
What is tRNA-synthesiser?
The tRNA-synthesiser is an enzyme that recognises the anticodons that the different tRNA brings to the ribosome, and thereafter connects it to the right amino acid
How many amino acids is a protein typical made up of?
A protein is typical made up of around 100 to 600 amino acids. But, some proteins are more complicated than others, and therefore use multiple amino acids chain, and like glutamatdehydrogenase use around 40 amino acids chains and around 8300 amino acids
Protein get their unique shape through specific amino acids and the folding of these acids. What are the four stages of protein folding?
- Primary structure. Here we gain the amino acids and the amino acid chains.
- Secondary structure. This is where the first folding happens, they fold in either beta-plates or helix structures.
- Tertiary structure. This is where the beta plates and the helix structures link up and begin folding thereafter.
- Quaternary structure. This is the finished protein
What are prion diseases?
Prion diseases like Creutzfeldt-jacobs disease is diseases where protein folding isn’t correct. These misshaped proteins can make other proteins fold like them, in a wrong way. Usually these get destroyed rather quickly but sometimes they don’t and this is where diseases can happen. Like mad cow disease, this is just a missfolded protein in the brain
What is a transcription factor?
A transcription factor is a protein that determines how often a gene will get expressed.
What is the difference between enchancer and silencer?
An enchancer is a area in DNA when bound by transcriptions factors will increase the activity of that gene.
A silencer on the other hand are then areas of the DNA when transcription factors attached will decrease the activity of said gene.
What’s the difference between a chromosome mutation and a gene mutation? And also, what is a point mutation?
Chromosome mutations involve the whole or a big part of the chromosome, while gene mutations is just changes to the order of bases that gets altered. A point mutation is where only one basepar gets mutated.
Which three ways does mutations happen?
Substituting, where it just get rearranged. Like a basepar gets swapped out for another basepar.
Insertion, where something gets added in. When one or multiple basepars gets added in.
deletion, where something gets removed. Where one or more basepars gets removed.
What are mutagens?
Mutagens are factors, or agents like radiation or chemical substances that can cause mutations.
What are cell differentiation?
Cell differentiation is where the cells gets the specific field of specialty, like some gets to be a muscle cell, or like a nerve cell. But also tissue and blood cells. This happens via which genes gets expressed.
Which enzyme separates the double helix structure?
Enzyme helikase
At the beginning of DNA replication, after the helicase splits the two strands, the next enzyme is primase, what does it do?
The enzyme primase makes the entry point to where to replication will start, this is called the primer. Eukaryotic cells have multiple start location, while prokaryotic only have one
The three enzymes helicase, primase and complex DNA-polymerase makes the three starter protein in DNA replication. What do they do?
Helicase is the one that opens up the double helix, making the replication possible.
Thereafter primase makes a primer marking the place to start, goes from 5’end to the 3’ end. The primer are around 5 to 10 nucleotides.
Then the enzyme complex dna-polymerase starts the replication process, going from the 5 end to the 3 end. There are multiple DNA-polymerase that works on the replication.
What enzyme glue together all the new fragments in the replication process?
The enzyme DNA-Ligase glues them together, this enzyme works from the 3 end to the 5 end
When errors occur in the replication process, like a G instead of T to the complementary A, which enzyme complex fixes the error?
A part of the enzyme complex DNA-polymerase fixes error that occurs. This enzyme complex does multiple things, so not only does it make a complementary thread but it also fixes erorrs
How many autosome and sex chromosomes do a person have?
A person has 44 autosome (22 pairs) and 2 sex chromosomes (1 pair)
Are male sex chromosomes homogolous?
No, because they have one X chromosome and one Y chromosome, a female on the other hand has a homogelous sex chromosomes, because they have two X chromosomes
What’s a telomere?
A telomere is the end of each chromosomes, this spot protects the chromosomes in terms of replication. And each replication the telomere gets shorter. This is why we can assess a person age from this.
Mitosis is separated by 5 phases and then cytokinesis. Describe the 5 phases with simple terms.
Proface: this is where the two chromosomes condenses to the point that we can see it with a light microscope. Also the spindle apparatus which are made up of microtubule starts getting made.
Prometaface: nucleus gets dissolved and the spindle apparatus attached to the sentromeres are the sister chromatids. These also moves towards the middle of the cell.
Metaphase: the chromosomes gets arranged each on their own.
Anaphase: the chromosomes gets separated, the spindle apparatus shortens and pulls the sister chromatids to each of ends. Results are two full sets of chromosomes at each of the ends.
Telophase: the spindle apparatus disappears and then two nucleuses gets made for each of the future cells. They decondenses and they start looking more like the linear strands that they are most of the time.
Then cytokinesis comes and separates all of the organelles and nucleuses and voilà, we have to diploid cells that soon goes into interphase again, where they will spend most of their time
In cytokinesis, what are the difference between plant and animal cells?
In plant cells there are multiple vesicles that contains material to cell walls that melt together and form a cell plate in the middle.
Animal cells on the other hand there almost like a string that winds itself up around the middle and separates the cell into two
What are gender cells called?
gametes, and these are diploid
What are meiosis?
Meiosis is the process of production of gender cells. This happens when the plant or animal produces a diploid cell that then separates into haploid gender cells. This process is a form of meiosis
What phases do meiosis have?
Like mitosis they have an interphase where in the s-phase the DNA gets replicated. After that we have meiosis 1 and 2.
These are like mitosis compared of the same 5 phases.
Proface, prometaphase, metaphase, anaphase and telophase.
Also cytokinesis happens after both meiosis I and meiosis II
How many times does cytokinesis happen in meiosis?
There are two instances of cytokinesis in meiosis, one after meiosis I and one after meiosis II
How many haploid cells gets made from meiosis?
There will be made four haploid cells of one instance of meiosis. This is because the one cell (haploid) gets into cytokinesis in meiosis I and then make two haploid cells, and then the two cells will go into cytokinesis and make four haploid cells (gametes)
What happens with the chromosomes in meiosis I and in meiosis II
The same process in the phases happens with the spindle apparatus happens and separation process.
But in meiosis I the homologous chromosomes gets divided into the two cells, and then in meiosis II the sister chromatids get separated. Unlike in mitosis this only takes one process, but this also only creates two cells instead of four.
When does the crossover happen and what does it mean?
The crossover in meiosis (only in meiosis) happens in prophase I, and this is where sections of the chromosomes gets swapped between the sister chromatids so they get a bigger variety.
What is homologous chromosomes?
It’s the identical match of a single chromosome, we have 22 autosomes chromosomes, each of these are homologous and then we have one pair of sex chromosomes. If a person is a female then it’s homologous, but if it’s a male then it’s not, XY.
