Hi, i got this question in a practise exam:
Explain why RNA must be converted to DNA in RT-PCR
2 mark question.

Is RT-PCR on the study design??

  • ohio replied to this.

    Taaaa76 this was a question from the 2022 biology exam. It is on the study design I think.

        Hi, I have a question on meiosis, when describing how it can increase genetic diversity. Is recombination the same as like crossing over and independent assortment? What would be the difference if they aren't?

        A sample answer I found to this question I was doing said, "The genetic material is transferred between homologous chromosomes during recombination"

          ava recombination usually just refers to crossing over, since that's when some of genetic material is swapped between the homologous chromosomes to create genetically distinct homologous chromosomes. Independent assortment just refers to the lining up of the chromosomes on the metaphase plate, the maternal and paternal chromosomes randomly swapping their position either side of each other and creating unique combinations either side of this plate. Hope that makes sense. Maybe check with your teacher to confirm this.

          • ava replied to this.

              Does anyone know what biological implications mean? Such as when they ask for a biological implication about GMOs. I am struggling to find out what the term actually refers to. Thanks!

                abbey1234321 This might help.

                Biological implications = What impact does this change or technology have on biological systems and processes

                Below includes pros and cons for GMOs

                Pros:

                • GM crops usually have better crop productivity than non-GM crops, meaning more food can be grown using less land, reducing habitat loss due to land clearing
                • Insect-resistant GM plants require fewer pesticides, which is better for the environment
                • GM foods can be made to have improved nutritional content, improving the health of individuals that consume them.

                Cons:

                • GM crops may lose their effectiveness if weeds or pests evolve resistance to them
                • Loss of genetic diversity within crop populations due to a lack of genetic variation when GM crops are widespread
                • Cross-pollination between GM crops and wild species or weeds may cause genes to spread and an have negative consequences on organisms (e.g. could damage them or reduce their fitness)

                    I had trouble with a question:
                    Carbon Dioxide is one if the products of cellular respiration that needs to be carried from the tissue to the lungs where gas exchange occurs. It mainly transported in the blood:
                    A) bound to haemoglobin
                    B) as carbonic acid in solution
                    C) as bicarbonate ions in plasma
                    D) associated with enzyme cytochrome c

                    I never learned about this, is this a question that could come in the exam?

                      I also had trouble with another question:

                      Which of the following events will not occur after infection by a virus?
                      A) release of interferon
                      B) release of complement
                      C) apoptosis in host cell
                      D) increase in the production of lymphocytes

                        I need help for once again, another question:

                        Eukaryotic cells have a single circle of mitochondrial DNA consisting of approximately 16.5 kilobases. Mitochondrial DNA is useful in establishing evolutionary relationships between individuals because:
                        A) it is only present in female gametes
                        B) recombination occurs at a regular rate
                        C) it is present in smaller amounts than nuclear DNA
                        D) substitution mutations occur at a greater rate than nuclear DNA
                        The answer is B and I have no idea why

                        Taaaa76 oxygen binds to haemoglobin, so I'm assuming the answer is A. This might be an old exam questions, since I don't recall body systems being part of the new study design.

                            Taaaa76 okay so when a virus enters a cell, the cell will release interferons as a warning signal for other neighbouring cells. Basically, it's warning its neighbours that a virus is in the body, and therefore A wouldn't be correct. Complement proteins will be released to try and recruit more leukocytes to the site of infection, so B wouldn't be correct. Production of lymphocytes, aka T and B cells will increase as antigen-presenting cells active the humoral and cell-mediated responses, so D is also incorrect. Apoptosis however is controlled cell death. This is used by the body to get rid of body cells that are damaged, dying, potentially cancerous, etc. Cells infected by viruses undergo lysis, at least according to VCAA (biology is a lot more complicated), not controlled cell death initiated by the body itself. Therefore, I reckon C is probably correct (I might be wrong though).

                                _sophiestudies_

                                The answer is B i shouldve clarified, my bad.
                                Also, dont virally infected cells also undergo apoptosis? Like a natural killer cell and cytotoxic t cell both induce apoptosis in an infected cell right?

                                    Taaaa76 okay yes that does make sense. Apoptosis would take place because of natural killer cells and cytotoxic T cells. My bad. You know what, it's a dumb question ahaha because complements would be released. Is this a VCAA question?

                                        Taaaa76 oh it's about carbon dioxide ahaha. I'm currently studying haemoglobin at uni so that's why I messed that up. Yes, CO2 is carried by bicarbonate ions in plasma, but I don't think you'll need to know about that.