Unit 5 Reflection

      In this unit we learned about genes and mutations. DNA is the code of life. It is made with a double helix which is two strands twisted around each other. It is made up of nucleotides which is made of a nitrogen base, phosphate group, and a sugar. The nitrogen bases wither come in double rings called purines such as adenine and guanine or single rings called pyrimidines such as thymine and cytosine. Semi-conservative replication is the process of creating two identical strands of DNA from one strand. the two strands end up with half of the original strand. The first step is unzipping, where the enzyme unzips DNA by breaking hydrogen bonds that hold nitrogen bases together. Then DNA polymerase adds matching nucleotides to each strand. The central dogma of biology is DNA to RNA which is transcription, then RNA to proten which is translation, and finally, protein to organism which is the phenotype. Transcription is the process where RNA polymerase reads and copies the DNA code for a protein as mRNA copy. The three steps of transcription are first DNA unzips, then RNA polymerase matches spare nucleotides to make an RNA strand, and finally, messenger RNA is produced and leaves the nucleus for the cytoplasm. Then in translation, mRNA arrives at the ribosome which reads the mRNA three bases at a time and translates DNA language to protein language.Each base sequence is known as a codon and each codon codes for one amino acid. The result is a long chain of amino acids which twists, folds, and combines with other chains and becomes a protein.
      We also learned about mutations, which is a change in the DNA code. Point mutations are a change in one or two base pairs of DNA. This is very small and common. The two main types are substitution and frameshift mutation.
     The most difficult part of this unit was about gene expression and regulation. Gene expression is the process of a gene ceing used to produce a gene product or phenotype. Gene regulation is mechanism used by cells to increase or decrease the expression of a gene. Every cell in our body has the same DNA but not all cells look the same. Cells look different because each type of cell expresses genes specific to those cells. Cells don't want to waste energy so thy have a variety of steps to control gene expression. There is a promoter, location on DNA where RNA polymerase attaches. The operon is a series of genes used to control the expression of a single gene.  The operator is a switch or segment of DNA at the start of a gene that prevents of allows RNA polymerase from attaching and reading the gene. An example would be the lac operon, where bacteria uses lactase to break down lactose.

Protein Synthesis Lab

     To produce protein, first is transcription. RNA polymerase matches reads and copies the DNA code for a protein as a messenger RNA copy. Then in translation, the messenger arrives at the ribosome. Then, the ribosome reads the mRNa three bases at a time and translates DNA language into protein language. The result is a protein! 

      Substitution seemed to have the least effect on the proteins since the protein ended up not changing at all. Deletion seemed to have the greatest effect. The protein became a lot shorter than it was originally, which meant a lot of information was left out. It does matter where the mutation occurs. If it was at the end, the results might have been different and only a small portion would've been left out. 

      I chose to do deletion again but in a different position because it seemed to change the protein the most. I took out one part from the very beginning, and it didn't change much from the first deletion. I feel like if I deleted a portion from the end instead, the results would have been different.

     Mutations affect our life since it could happen to any one of us. Mutations are the reasons for why cancer and other diseases happen. One disease that is caused my mutations is phenylketonuria. Without treatment it causes intellectual disabilities. 

DNA extraction lab

The question was How can DNA be separated from cheek cells in order to study it. In this lab we had a procedure and tried to group them according to the three basic steps: homogenization, lysis, and precipitation. We swished Gatorade around in our mouth and spit it back out. The Gatorade homogenized it. The Gatorade and saliva mixture didn't mix and the DNA precipitated because the Gatorade was polar and the alcohol was non polar. One possible error we made was when we put the alcohol in. If we didn't carefully add in the alcohol, then the two solution could have mixed and we wouldn't have been able to see the DNA. To improve this I would recommend people to carefully pour in the alcohol. Another possible error was that we didn't swish around the Gatorade in our mouth enough. This wouldn't have gotten enough DNA in the solution which would've affected how it formed later.


 

Unit 4 Reflection

This unit was about the cell cycle, genetics, The cell cycle is a series of steps that take place when a cell duplicates or reproduces. Three reasons for the cell cycle is reproduction, growth and development, and cell and tissue repair. There are two types of reproduction, sexual and asexual. In asexual reproduction , there is only one parent. All the offspring are genetically identical. Some benefits of asexual reproduction is that it's easy, takes a short amount of time, you don't need a mate, and can make lots of offspring. The cost is that there is no genetic variation and is will make it more likely to go extinct if a new pathogen attacks them or their environment changes. The benefits of sexual reproduction is that it creates genetic variation, can allow the parents to raise the young to ensure survival, and create competition for mates, ensuring the best pass on their genes. The cost is that it requires lots of energy and time. It exposes you to parasites and STDs. It could create genetic combinations that are bad. We also learned that all body cells are diploid and all gametes are haploid. In meiosis, there are four stages just like mitosis, but in meiosis it divides twice. Homozygous is having two of the same allele while heterozygous is having two different alleles. The law of segregation states that the gene pairs for a trait separate when gametes are formed. The law of independent assortment states that the gene pairs separate randomly from each other during meiosis. Autosomal inheritance is when an organism inherits or gets the gene responsible for a trait from all the other 22 chromosomes which are called autosomes. X-linked inheritance is when an organism inherits, or gets, the gene responsible for a trait from the x chromosome. The most difficult thing to understand in this unit is probably crosses. A dihybrid cross is comparing two genes at the same time and the phenotypic ration is 9:3:3:1.
My preferred learning style is kinesthetic and these results were expected. I will still try to study in different ways but copying down diagrams would probably be helpful to me for studying.

Coin Sex Lab

In this lab, we flipped coins to simulate the randomness of alleles. The coins were the genes and the sides were like the different alleles. This simulated the process of meiosis and the recombination of these genes. This showed how random it is. There is a very low chance of getting homozygous genotypes in dihybrid crosses. You can see what the probability of something is, but you'll never know what you will actually get. The coin flipping was also gene segregation and the results after flipping was the recombination. In part two we tested autosomal dominance, the ones on the 22 chromosomes. In part 3 we did an experiment on x-linked recessive traits, which in this experiment we used the allele for colorblindness. X-linked inheritance is the trait you get from the x chromosome. Monohybrid was the ones we did using only one gene. We also found the different probabilities for either heterozygous or homozygous phenotypes. For the first experiment, the females were homozygous x. Males were heterozygous. Our last experiment was dihybrid, and tested for the different colors of hair and eyes. It was wither brown or blonde hair and brown or blue eyes. This experiment showed that neither trait affected the other and it was possible to get lots of different combinations. This relates to our life because it shows what the probability is of getting certain traits for our offspring.

Genetics Infographic

Link to a bigger image:  https://magic.piktochart.com/output/8996330-genetics

Unit 3 Reflection

In this unit we learned about the cell theory, activation energy, membranes, osmosis and diffusion, what a cell does, photosynthesis, and cellular respiration, The most challenging thing about this unit is cellular respiration. There are three steps to cellular respiration. The first step to it is glycoolysis which occurs in the cytoplasm. 2 ATP molecules are produced for one glucose molecule in this step. The second step is the Krebs cycle which converts molecules from glycolysis into 2 ATP, carbon dioxide, and electron carrying molecules. The final step is the electron transport chain which occurs within the inner membrane of mitochondria. It uses oxygen, NADH, and FADH2 to convert ADP into ATP. 32 ATP is produced in this step. This whole process produces a total of 36 ATP, 6 carbon dioxide, and 6 water. Cellular respiration is the process of cells braking down glucose into energy. Photosynthesis is where plants produce glucose and oxygen using sunlight and carbon dioxide. Autotrophs carry out photosynthesis and can be macroscopic or microscopic. They can be multicellular of unicellular. Mesophyll cells are a collection of cells containing chloroplasts. A chloroplast is an organelle containing stroma and grana. Stroma is the space inside chloroplasts and grana is a stack of thylakoids. Thylakoids are membranes that contain chlorophyll. A light dependent reaction occurs in thylakoids of grana. Light is absorbed and energy is transferred between molecules by the electron transport chain. It produces NADPH and ATP. Water is split which releases oxygen and pumping H+ ions into the thylakoid membrane. ATP synthase uses H+ movement to produce ATP. ATP synthase facilitates diffusioin of H+ from high to low concentration. As H+ moves from thylakoid to stroma, ATP is produced. In a light independent reaction, it produces sugar from carbon dioxide using ATP and NADPH from light reactions. The calvin cycle rotates 6 times to produce 1 glucose molecule. I learned a lot from this unit but there is still a lot to learn about biology. I learned a lot about cellular respiration and how photosynthesis works.