Wednesday, November 25, 2015

Unit 4 Reflection

This unit was about Sex in Genetics. We learned about the cell cycle and its reasons which includes Reproduction, Growth and Development, and Cell tissue and repair. The steps of the cell cycle is Interphase, mitosis and cytokinesis. In interphase, cell grows, copies itself and prepares for division. In mitosis, it consists of prophase, metaphase, anaphase, and telophase. In prophase, DNA becomes visible. In metaphase, chromosomes line up at the equator. In anaphase, spindle fibers pull the chromosomes apart and in telophase, new nuclear membranes form and spindle fibers disappear. In cytokinesis, the cells split into two identical cells, the rest of organelles are divided and the cell membranes pinch apart. We learned about the reason why sex is great because of asexual and sexual reproduction and its cost and benefits. Sex can create sex cells which can create offspring. Sex chromosomes can create sex and can be determined by autosomes. It also includes Meiosis which is the process of making gametes. The steps of meiosis is the same as mitosis but but meiosis divides twice. There is Meiosis I and Meiosis II and Meiosis I splits homologous chromosomes and Meiosis II splits sister chromatids. It also involves crossing over.

We learned about Mendel's laws which are the law of segregation and the law of independent assortment. The law of segregation states that gene pairs for a trait separate when gametes are formed and the law of independent assortment is when gene pairs separate independently.  We learned about his discoveries of sex by crossing purebred purple and white together. That when he discovered that traits are determined by two copies of a gene. He later realized that sex is great because he could predict the phenotype of an offspring if he knew the genotype of the parents. We learned about calculating the chances of a certain offspring by using punnett squares.

Lastly, we learned about the different types of crosses. The types of crosses we learned was the monohybrid cross, the dihybrid cross, and the test cross. The monohybrid cross crosses homozygous dominant with homozygous recessive, dihybrid cross crosses double homozygous dominant with double homozygous recessive and test cross crosses unknown individuals with known homozygous recessive individuals. We also made an infographic about genetics and it helped me learn more about it.

In this unit, I learned a lot about genetics and sex. I never knew that sex was so useful in life and I though it was something that was inappropriate to talk about. This unit helped me build up on more genetics that I had learned in 7th grade. From the infographic, I learned more about the background of genetics and how to make infographics.
https://upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Independent_assortment_%26_segregation.svg/2000px-Independent_assortment_%26_segregation.svg.png





https://upload.wikimedia.org/wikipedia/commons/d/d3/Gregor_Mendel.png

Thursday, November 19, 2015

Coin Sex Lab Relate and Review

In this lab, we flipped some coins to determine the traits that a child could have by probability. We tested for sex of offspring that included getting heterozygous and homozygous combinations, autosomal dominance, x linked recessive to find x linked inheritance, and dihybrid crosses to find possibilities for traits that can be made from each genotype. The coins served as a model for genetics by the way it was demonstrated. The coins are the Genes and the coin flipping in the air is meiosis or gene segregation to create alleles. Meiosis from the coin flip created recombinations of crosses of genes to create phenotypes. In the dihybrid cross simulation, the expected results for this simulation was that out of 16 individuals, 4 individuals would have brown hair, brown eyes, 4 individuals would have brown hair blue eyes, 4 individuals would have blonde hair, brown eyes, and 4 individual would have blonde hair. As a result, 12 people would have brown hair, brown eyes, 2 people have brown hair, blue eyes, 1 will have blonde hair, brown eyes and 1 will have blonde hair, blue eyes. These results reflect on how probability can be affected. The results that can be obtained using probability is that probability is mostly not accurate comparing to results that should be expected to get. The limits of using probability for predicting our offspring's traits is that we would not know what kind of possibilities to expect when genotypes cross to form phenotypes. It also would affect our knowledge of punnett squares and how they are used for predicting offsprings. This helps me understand how sex works when it comes to predicting offsprings and traits. With this knowledge, I can use it to tell what kind of person I am. I can figure out what kind of traits I would have right now and tell what kind of offspring I got these traits from.