Tuesday, November 22, 2016

Coin Sex Lab and Unit 4 Reflection


     In the coin sex lab, we flipped coins to show the probability of the phenotype of an offspring. The coins demonstrated the probability of a child inheriting their parents' genes. In the dihybrid cross, two individuals were both double heterozygous. The dominant alleles were brown hair (B) and brown eyes (E). The recessive alleles were blonde hair (b) and blue eyes (e). Meiosis is the process of making gametes in testes or ovaries. There were two different possibilities for meiosis. By completing the Punnett Square, I found that the expected outcome was 9 offspring with brown hair and brown eyes, 3 offspring with brown hair and blue eyes, 3 offspring with blonde hair and brown eyes, and 1 offspring with blonde hair and blue eyes. After flipping the coins and collecting my data, I found that Punnett Square is an accurate representation in predicting the phenotype of an offspring. I got 9 offspring with brown hair and brown eyes, 3 offspring with brown hair and blue eyes, 3 offspring with blonde hair and brown eyes, and 1 offspring with blonde hair and blue eyes when flipping the coins.
     The autosomal dominance lab determined the probability of having a bipolar offspring if one parent is heterozygous for the trait and the other parent is homozygous and does not have the trait. The Punnett Square was a monohybrid of Bb x bb, where B is the bipolar allele and b is the normal allele. I predicted that 50% of the offspring would have the bipolar disorder. After flipping the coins and collecting the data, I came to the conclusion that 4 offspring had bipolar disorder, and 6 were normal. Although the Punnett Square was not a completely accurate representation of my results, the Punnett Square was pretty close to accurate.
     In the X-Linked Recessive part of the lab, the female was a carrier of colorblindness, and the male had normal color vision. The Punnett Square was a monohybrid of X^B X^b by X^B Y. Through  recombination, the alleles from each parent combined. One offspring was colorblind, and the other nine offspring were normal. When using probability to predict an offspring's traits, a person cannot assume what traits an offspring can have. Instead, they can predict the likelihood of a trait being dominant.

    This unit was about the cell cycle, asexual vs. sexual reproduction, meiosis, Punnett Squares, Mendel's Sex Laws, and genetic exceptions and complications. The cell cycle has three steps: interphase, mitosis, and cytokinesis. In interphase, DNA is copied. Mitosis is the process in which DNA and organelles are split up. Cells divide into two cells during cytokinesis. 

     Asexual reproduction requires one parent. The offspring is genetically identical. Asexual reproduction is easy, takes a short amount of time, does not need a mate, and can make a lot of offspring. Asexual reproduction has no genetic variation, is not resistant to change. The offspring of asexual reproduction are more likely to go extinct if their environment changes. Sexual reproduction requires two parents, and each parent contributes half of offspring's DNA through sperm or egg. Sexual reproduction creates genetic variation, and new traits arise in the population. The costs of sexual reproduction requires a lot of time.
     Sex is determined by a pair of sex chromosomes. Homologus chromosomes are chromosomes that come in pairs, in which one there is one copy from each parent. Sex cells are called gametes. Males produce sperm, while females produce egg. Haploid cells are sex cells that have half of the chromosomes. All body cells are diploid, meaning that cells have two copies of every chromosome. Asexual reproduction always produces diploid cells. 
     Meiosis is the process of making gametes in testes or ovaries. There are four stages in meiosis, but the cell divides twice, meaning that a cell goes through the four stages two times. The four stages are: prophase, metaphase, anaphase, and telophase. The process of meiosis 1 splits homologus chromosomes. Meiosis 2 splits sister chromatids. 
     A trait is a characteristic. A gene is a piece of DNA that gives an organism its trait. Gregor Mendel experimented with pea plants and mated peas to observe their traits. He discovered that traits are determined by two copies of a gene. Some versions of a gene are dominant over the others. A genotype is the alleles that an organism has. A phenotype is the physical trait that results due to an organism's traits. Individuals that have the same two alleles are called homozygous. Individuals with two different alleles are heterozygous. 
    The Law of Segregation, a principle introduced by Mendel, states that the gene pairs of a trait separate where gametes are formed because of meiosis. The Law of Independent Assortment states that gene pairs separate independently, or randomly, from each other during meiosis. The Punnett Square predicts possible genotypes of gametes. 
     Autosomal inheritance is the process in which an organism inherits the gene responsible for a trait from all the 22 autosomes. X-Linked inheritance is when an organism inherits the gene responsible for a trait from the x-chromosome. 
     Incomplete dominance happens when neither allele is dominant nor completely recessive. Both alleles will both be completely expressed in codominance. In other words, codominance has both phenotypes. Codominant alleles are neither dominant nor recessive. 
     Because chromosomes have many genes, the closer they are together, the more likely they are to be inherited together through gene linkage. In epistasis, one gene alters the phenotype of another gene. Multifunctional disorders are disorders where an environment affects genetics. Most humans are polygenic because they have two or more genes to determine their phenotype. 

     http://bit.ly/2fvBp72
     This unit was very fun because I really liked learning about Punnett Squares and how they can determine the probability of an offspring having a specific genotype. I struggled to understand the difference between meiosis and mitosis so I did some extra research. I understood how some versions of alleles could be dominant over others, but I had a difficult time figuring out how codominance works. In my opinion, the infographic helped me get a better understanding of the main concepts from this unit. I definitely feel that I am a better student than I was yesterday because I have expanded my knowledge in biology. I would like to know more about the works that Mendel did to influence the world of biology today.  

Picture of my infographic: https://magic.piktochart.com/output/17955851-genetics





Monday, October 31, 2016

Sexual vs. Asexual Benifits

Is sexual reproduction important?
     Sexual reproduction is necessary for life. "[Sex] prevents parasites from becoming too well adapted to their hosts" (Judson 228). Sexual reproductions remove harmful mutations from the population. Sexual reproduction has a slower production rate. "Sex is an advantage because it breaks up gene combinations" (Judson 229).
     Asexual reproduction does not require fertilization, but there is very little variation, which can cause extinction. "...mammals clone once in a while, when an embryo splits early in development" (Judson 215).
     Some animals reproduce sexually and asexually. "Armadillos... engage in both sexual and asexual reproduction"(Judson 229).
     I learned that many species reproduce in different ways. Some reproduce more than others, and some reproduce sexually, while others reproduce asexually. I understood the text and all my questions were answered in the text.

Wednesday, October 26, 2016

Unit 3 Reflection

     Unit 3 was about cells and their functions. Macromolecules serve as the building blocks for life because they make up different parts of the cell and they all serve different purposes. The cell theory states that all things are composed of cells, a cell is the basic unit of life, and new cells generate from existing cells. Prokaryotic cells have no nucleus, while eukaryotic cells have a nucleus.
     Membranes and their unique characteristics are so essential for life because they all have different functions that are necessary for life. The nuclear membrane holds DNA in the nucleus and allows RNA to leave through the pores. The lysosome holds enzymes for recycling proteins. The endoplasmic reticulum (ER) holds proteins as they are finished off and holds lipids as they are made. The vesicles export molecules in and out of the cell. The golgi apparatus packages and releases finished proteins, lipids, and hormones. The membranes in chloroplasts and mitochondria creates carbohydrates through the process of photosynthesis, and breaks down carbohydrates through the process of cellular respiration. The cell membrane holds all cell contents inside and protects from the outside environment. The cell membrane also controls the passage of molecules inside.
       Semipermeable membranes allow some molecules to cross the membrane, while others can not. Passive transports require no effort or energy. Active transports use energy to bring rare but highly needed molecules into the cell. Diffusion is the movement of small molecules from high to low concentration through the lipid bilayer. Proteins that make it possible for large molecules to pass through the membrane through the process of facilitated diffusion. Osmosis is the diffusion of water across selectively permeable membrane. An isotonic solution is when the solute concentration is the same outside and inside the cell. A hypertonic solution is a solute concentration that is greater than that inside the cell. A hypotonic solution is a solute concentration that is less than that inside the cell.
     Cells specialize in making proteins. Mitosis is the process in which one cell reproduces by dividing into two cells. Photosynthesis converts light into chemical energy. A cell creates energy by creating ATP  from glucose to power the cell. The endosymbiotic theory explains how a large cell ingested bacteria and became part of it.
     Photosynthesis is the process in which plants produce glucose and oxygen using sunlight and carbon dioxide. Light dependent reactions occur in the thylakoids of grana. Light independent reactions occur in the stroma.
     Cellular respiration is the process of breaking down glucose into energy. It has 3 stages: glycolysis, krebs cycle, and the electron transport chain. Glycolysis produces two ATP for every one glucose molecule. The Krebs Cycle coverts molecules from glycolysis into two ATP, CO2, Nadh, and FADH2. The electron transport chain uses oxygen, NADH, Fadh2, and converts ATP into ADP. This last stage produces 32 ATP.
     The process of photosynthesis and the process of cellular respiration undo each other. Photosynthesis occurs in the chloroplasts in autotrophs, while cellular respiration occurs in the mitochondria in autotrophs and heterotrophs.
     Overalll, I really enjoyed this unit. I liked learning about photosynthesis and cellular respiration. I had a tough time remembering the function of each organelle in a  cell. I had a fun time looking at cells under a microscope, and I realized how complicated a single cell can be. 

Sunday, October 23, 2016

Photosynthesis Virtual Labs

Lab 1: Glencoe Photosynthesis Lab

Analysis Questions
1. Make a hypothesis about which color in the visible spectrum causes the most plant growth and which color in the visible spectrum causes the least plant growth?
If the color in the visible spectrum is blue or red, then the plant will grow bigger.
If the color in the visible spectrum is green, then the plant will grow the smallest.
2. How did you test your hypothesis? Which variables did you control in your experiment and which variable did you change in order to compare your growth results?
I tested my hypothesis by planting spinach in all the different lights for 30 days. Then I did the same for the radish and lettuce.In my experiment, the controlled variable was the type of plant. The variable that I changed to compare the growth was the color of the light.
Results:
Filter Color
Spinach Avg. Height (cm)
Radish Avg. Height (cm)
Lettuce Avg. Height (cm)
Red
18
12
12
Orange
16
7
5
Green
3
2
3
Blue
18
15
12
Violet
15
11
7


3. Analyze the results of your experiment. Did your data support your hypothesis? Explain. If you conducted tests with more than one type of seed, explain any differences or similarities you found among types of seeds.
My data supported my hypothesis. I predicted that the blue light and the red light would show the most plant growth and that green light would show the least amount of plant growth. I found that spinach grew best under the red light and the blue light. The radishes showed the second most amount of plant growth under red and blue light. The lettuce showed the least amount of plant growth under red and blue light compared to the spinach and the radish.
4. What conclusions can you draw about which color in the visible spectrum causes the most plant growth?
I conclude that blue light causes the most plant growth in the visible spectrum.
5. Given that white light contains all colors of the spectrum, what growth results would you expect under white light?
I would expect a normal rate of growth under white light because white light is an average of all light lengths.

Thursday, October 20, 2016

Microscope Lab

Microscope Lab
Power: 400x
The amoeba is unique because it has pesudopods, whcih surround food and pull the food into the cytoplasm.
The amoeba has purple and blue pesudopods.
It is a eukaryotic cell, and it is heterotrophic. 


Power: 400x
The euglena is unique because there are dark circles inside the cell.
The euglena is green because it has chloroplasts.
It is a eukaryotic cell, and it is heterotrophic and autotrophic. 


Power: 400x
The cyanobacteria has no chloroplasts because it has no green pigments.
The cyanobacteria looks like blue links of sausage.
It is a prokaryotic cell, and it is autotrophic. 


Power: 400x
The bacteria cells is unique because it consits of cocci, bacilli, and spirillums.
The bacteria cell has many visible spirllum, which looks like a spiral twist.
It is a prokaryotic cell, and it is autotrophic. 


Power: 400x
The spirogyra is unique because it has visible spirals.
The spirogyra is green because it has chloroplasts.
It is a eukaryotic cell, and it is autotrophic. 
Power: 100x
The ligustrum is unique because it has long cells.
The ligustrum is green because it has chloroplasts.
It is a prokaryotic cell, and it is autotrophic. 


Power: 400x
The skeletal muscle tissue is unique because it has many nuclei.
This animal cell looks like blocks and strings.
It is a eukaryotic cell, and it is heterotrophic.

Thursday, October 13, 2016

Egg Diffusion Lab

Egg Diffusion Lab
     In this lab, we asked the question: how and why does a cell's internal environment change, as it's external environment changes? We placed the egg in vinegar for 48 hours to dissolve the outer shell, to make the membrane visible. Then, we measured the circumference of the egg and the mass. After, we put one egg in water, and the other in corn syrup. The corn syrup egg had a 44% decrease in mass, and the circumference had a 26.16% decrease. There was a significant decrease because the water solvent and the sugar solute made the egg diffuse into a high concentration.
     A cell's internal environment changes as it's external environment changes. This change is due to one of the theories of life, homeostasis. Homeostasis is the tendency towards maintaining a stable equilibrium. Passive diffusion changes the internal environment of the cell. Low concentration outside the cell, and high concentration inside the cell is a hypertonic solution.
    This lab demonstrates the biological principle of diffusion. The egg loses water when it is surrounded in corn syrup because it is a hypertonic solution. The egg gets filled with water through the process of diffusion because it is a hypotonic solution.
     Sprinkling fresh vegetables at markets with water keeps them firm and hydrated so they appear fresh and good looking for the buyer. Since water is hypotonic to vegetables, water has fewer solutes and a higher concentration of water than inside the vegetable cells. This makes more water diffuse into the vegetable cells than the amount of water that difuses out of the vegetable cells. More water inside the cells makes the vegetables firm. Roads are salted to melt ice because salt lowers the freezing point of water. Lowering the freezing point makes it possible to take advantage of a lower melting point. As the water and salt dissolves on the road, it forms a salt solution.  Outside of plant cells, this is a hypertonic solution. The hypertonic solution causes the water in the plant cell's cytoplasm to move out of the cell through the process of osmosis. The inside of the cell becomes dehydrated, making the cell and the plant die.
     Based on this experiment, I would like to test a different substance, other than an egg, to see if the substance has the same affect on hypertonic and hyoptonic solutions. I would like to see if the substance also expands when it is placed in water, and if it shrinks when it is placed in sugar water.

Monday, October 10, 2016

Egg Macromolecules Lab

Egg Macromolecules Lab
     In this lab, we asked the question can macromolecules be identified in an egg cell? In the egg membrane, when a mixture of sodium hydroxide (NaOH) and copper sulfate (CuSO4) was added, the solution tested positive for proteins. The membrane changed to a lavender color. It scored a 5 out of 10 points on a scale of amount of color change. This happened because there are transport proteins in the egg membrane that keep bacteria out. The egg white tested positive for proteins when a mixture of sodium hydroxide (NaOH) and copper sulfate (CuSO4) was added. The egg white turned dark purple, and earned a 7/10 on the color changing scale. The egg white tested positive for proteins because there are structural proteins used as food, and enzymes in the immune system break up bacteria. The egg yolk tested positive for lipids. The yolk changed to a medium red color and earned a 7 out of 10 on the color changing scale. Lipids can be found in the egg yolk because lipids store energy and sugars in the egg yolk.
    While our hypothesis supported was supported by our data, there could have been errors due to the egg yolk not mixing in with the solution. Due to these errors, in my future experiments I would recommend making sure the solution mixes before testing my hypothesis. I would also recommend using a pipette to mix the solution.
     This lab was done to demonstrate where macromolecules are found in a cell. From this lab, I learned where monosaccharides, polysaccharides, proteins, and lipids can be found in an egg, which helps give me a hands on activity showing where macromolecules can be found in a cell. It also helps me understand the structure of a cell. Based on my experience from this lab, I can find each of the macromolecules in a cell and I understand how important it is to consume every type of macromolecule.