Unit 5 Reflection/ Notes

Unit 5 was the unit based off of… mutations. Problems with DNA, sometimes good, sometimes harmless, and sometimes detrimental. This unit went over point mutations, frameshift mutations, inversions, and translocations.

Point mutations are changes in one or two base pairs of DNA, and are small but common. These can be harmful if the protein changes a lot, but if the protein doesn’t really change they’re harmless. There are two main types of point mutations; substitution and frameshift mutations. In substitution, a nucleotide is substituted for another(ex. T is replaced by A by mistake). Frameshift mutations occur when a, insertion, where an extra base pair is added into the code, or b, deletion, where a base pair is left out of the code.

Some other mutations include inversion, where a piece of DNA breaks off and bonds in reverse order. Translation occurs when part of a chromosome breaks off and bonds with another chromosome.

Why do mutations matter to us though? First off, changes in DNA means changes in proteins, and some diseases are caused by the smallest of things, even a change of a single base. Mutations can be detrimental like said earlier, resulting in cancers or life threatening problems. Mutations can be very useful too. They could accidentally create new genetic variation for natural selection, causing resistances to certain things in nature.

Gene regulation is the reason why we don’t sprout hair on our eyes and ears on our chest. Cells don’t want to perform more than the necessary actions for the cell to function, so there is something called an operator that prevents the RNA polymerase from reading the gene. This is necessary, because without the operator the RNA polymerase would read the gene and keep making excess amounts of whatever results from the initiated process.

Unit 4 Notes

Unit 4 consisted of many steps and processes, all related to cells and development.  

• DNA fingerprinting- analyzes sections of DNA that have little to no known function but vary widely from one individual to another.     

• Gene theory- whenever there is an absent or faulty gene, it is replaced by a normal and working gene.
• The Human Genome Project- ongoing effort to analyze human DNA sequence.

Punnett squares are extremely useful  charts, made to draw possible phenotypes of an offspring based upon its parents’ genes.

Mendel’s work showed people the reason why we all look different, and why we all have different traits. His work taught us about dominance, recessiveness, and variation.

Two types of Inheritance: Autosomal and x-linked.

The Law of Segregation- Gene pairs for a trait separate when gametes are formed

Unit 3 Notes

Cells are called cells because a scientist, Robert Hooke, used an early compound microscope to look at a thin slice of cork. This cork showed many little chambers, almost as if they were “cells”. Hooke called these little chambers cells and they are known as cells to the present day. He used this microscope to look at other things, and found out that everything he looked at had “cells” as well.

The cell supports itself using different processes. Some of these processes create new organelles, some exterminate old, unproductive organelles, and some let things in and out of the cell.

Prokaryotes are cells with no nucleus, and lack many organelles compared to a eukaryote, which has all of those.

Unit 2 Notes

Photosynthesis is a process a plant cell undergoes to create ATP for the cell to work and for the plant to be supplied with energy. It converts energy from the sun and water from the roots in the soil to ATP using photosynthesis, which occurs in the chloroplast unique to plant cells.

Nucleus- nucleolus

Ribosome- small subunit(bottom), large subunite(top), builds proteins

Vesicle- membrane bound container

Rough ER- ribosome son the outside, “factory”

Golgi body- add stuff to proteins then “ships” the proteins

Cytoskeleton- structure

smooth ER- produces lipids, cholesterol, etc, detoxification

Mitochondria- produce atp, have own DNA

Vacuole- in plants, stores stuff

Cytosol- fluid that contains solutes, concentration gradient

Lysosome- Digestive enzymes, “suicide”

Centriole- important in positioning, initiate formation of spindle

Unit 1 Notes

Scientific method

1. Question/ problem
2. Collect information
3. Hypothesis
4. Experiment
5. Results/ data
6. Analysis/ conclusion(support/reject)

Qualitative- Descriptions

Quantitative- Numbers

Positive control- a group of data that will give predictable positive results

Negative control- A group of data lacking what is being tested so as to give expected negative results

Control- Something you use to compare your results to

Independent Variable- something that will change

Dependent Variable- something that will be measured

Constant- remains the same throughout experiment

Vocabulary

• Mutations- a change in the DNA code
• Mutagen- anything that causes a mutation
• Gene expression- process of a gene being used to produce a gene product or phenotype
• Gene regulation- mechanism used by cells to increase or decrease the expression of a gene
• Exons- sequences that are expressed
• Introns- sequences that are cut out
• Codominance- both traits are visible
• Incomplete dominance- Both partially show

Unit 5 Reflection

Unit 5 Reflection/ Notes

Unit 5 was the unit based off of… mutations. Problems with DNA, sometimes good, sometimes harmless, and sometimes detrimental. This unit went over point mutations, frameshift mutations, inversions, and translocations.

Point mutations are changes in one or two base pairs of DNA, and are small but common. These can be harmful if the protein changes a lot, but if the protein doesn’t really change they’re harmless. There are two main types of point mutations; substitution and frameshift mutations. In substitution, a nucleotide is substituted for another(ex. T is replaced by A by mistake). Frameshift mutations occur when a, insertion, where an extra base pair is added into the code, or b, deletion, where a base pair is left out of the code.

Some other mutations include inversion, where a piece of DNA breaks off and bonds in reverse order. Translation occurs when part of a chromosome breaks off and bonds with another chromosome.

Why do mutations matter to us though? First off, changes in DNA means changes in proteins, and some diseases are caused by the smallest of things, even a change of a single base. Mutations can be detrimental like said earlier, resulting in cancers or life threatening problems. Mutations can be very useful too. They could accidentally create new genetic variation for natural selection, causing resistances to certain things in nature.

Gene regulation is the reason why we don’t sprout hair on our eyes and ears on our chest. Cells don’t want to perform more than the necessary actions for the cell to function, so there is something called an operator that prevents the RNA polymerase from reading the gene. This is necessary, because without the operator the RNA polymerase would read the gene and keep making excess amounts of whatever results from the initiated process.

Human DNA Extraction Lab

Human DNA Extraction Lab

“How can DNA be separated from cheek cells to study it?” That was the question we stated our claim off of, which was homogenization, lysis, and precipitation. We swished gatorade around in our mouths to fill it with cheek cells, and after that we put salt, the enzyme for this, and dish soap. After this, we slowly poured alcohol into the test tube, and the DNA slowly diffused into the alcohol. This data supports our claim because it follows homogenization, lysis, precipitation and it allows us to study the DNA.

Our data agrees with the expected results because our steps, if followed correctly, were supposed to yield some DNA in the alcohol, which is what happened. There could have been errors with exact drop measurements, which could allow for too little DNA or the alcohol might not have separated from the soapy gatorade. There also could have been mistiming on how long we let the gatorade sit for, which might have limited the amount of DNA that came out. We could have solved these problems by using more precise measurements with drops, and by starting the timer exactly when we spit it out.

This lab was done to demonstrate the process used to collect DNA from a sample. From this lab I learned how to collect DNA from a sample, and this can help people in real life because of investigations. Based on my experience from this lab, I will be able to produce real DNA samples in the future, and DNA is so much more interesting to me now.