Biology: The Cell Theory 1. How did Janssen's, Hooke's, and Leewenhoek's work contribute to the work of the scientists that came after them? On 1590, Zacharias Janssen is the first person to invent the compound microscope. His invention allowed an English scientist, Robert Hooke to use the microscope to view the cell walls of a piece of cork in 1663. Then, Robert Hooke discovered the cell in 1665. He saw a multiple of tiny pores that he says looked like a jail bar or wall compartments. Because of this, Hooke called them cells. However, Hooke did not know their real structure or function. Hooke's description of these cells was published in Micrographia, a book that he published in 1665 about first applying the word "cell" to describe the basic unit of life. On 1670, Anton Van Leeuwenhoek, a Dutch biologist looks at pond water with lenses that he made. These lenses led to the building of Leeuwenhoek’s microscopes that is considered as the first practical microscopes and the biological discoveries for which he is famous for. Leeuwenhoek was the first person to see and describe bacteria in 1674.
2. How would our lives be different if we had never realized the existence of microorganisms? Provide at least one example to support your answer. Even though sometimes microorganisms can cause a bad influence to living things such as humans, animals, and plant. However, they also have a huge important role in our lives. Many microbes help to prevent disease and benefit the body. Also, microbes have been used to produce many vaccines and antibiotics. If we never realize the existence of them, then there will be no any medicine that could cure people from any medical conditions. Also, bacteria are used to make variety food products. Without them, it would be impossible to make cheese, yoghurt and other milk products. The most important bacteria in food manufacturing is lactic bacteria. Lactic bacteria are responsible for the taste and the texture of the milk products. It also gives the cheese its moisture.
3. Describe the concept of spontaneous generation. Why do you think it took such a long time for people to accept that this idea was incorrect? Spontaneous generation is a theory stating that living organisms could develop directly and rapidly from non living material. It was a common knowledge that the late nineteenth century people including scientists believed that simple organism like worms, frog and salamanders could come from dust, mud and others. People took such a long time to accept that this theory was incorrect because on the late nineteenth century, people don't have any enough evidence to tell that the theory was wrong.
4. How do you think the cell theory impacted later scientific discoveries? Explain your answer. The discovery of the cell theory has impacted the modern science. The cell theory gives scientists a better understanding about cells and their function which helped them find out more about organisms. With the discovery of cell theory, scientists find out that there are two types of organisms, prokaryotic and eukaryotic. It also help scientists to develop new ideas and make accurate conclusion of their findings.
5. How does this demonstrate the true nature of science? Nature of science refers to various topics, such as; sociology, philosophy, and history of science. The true nature of science is about developing theories and testing those theories. Once one theory is disprove, then you can develop new theories.
6. Review Pasteurs Experiment A. What was Pasteur's question? Where do the microbes come from to cause broth to decay?
B. State a reasonable hypothesis based upon this question Microbes come from cells of organisms on dust particles in the air, not from the air itself.
C. What was the independent variable in Pasteur's experiment? What was the dependent Variable? The independent variable was whether or not the flask had a curved or straight neck. The dependent variable was whether or not the broth showed any growth.
D. What did Pasteur conclude from his experiment? He concluded that the germs that exists in the air were able to fall.
7. How long did it take to develop the cell theory? What does this imply about formulation of a theory? Robert Hooke first found and named cells in 1662. The principals of cell theory was discovered by several people along the time scale. The second principal (all living organisms are made of one or more cells) was noted on 1839 by Schwann. The final principal (all cells result from pre-existing cells) was noted on 1849 by Rudolf Virchow.
8. Why do we still consider the cell theory a theory? The cell theory is still consider as a theory because there is no evidence of how the first cell is formed.
ANalogy of cell
Analogy of cell: Airplane
Cell membrane/Security
- Cell membrane controls what goes in and out - The security controls wether people are allowed to go in or not
Nucleus/Pilot Nucleus is the brain of the cell The captain is the person who give instruction and give direction to all the people on board
Nucleolus/Co-Pilot
The nucleolus is like the Co-Pilot. They both have a similar job to nucleus and pilot. The Co-Pilot assists the pilot. Same thing like the nucleolus assists the Co-Pilot.
Mitochondria/Engine
Mitochondria is the power house of the cell The engine is the source of power that allows the plane to fly
Cytoplasm/Stewardess
Cytoplasm keeps everything in place Stewardess controls the service for the passengers. So that everything runs smoothly and keeping everything in its place.
Ribosomes/Chef
- Ribosomes makes proteins to give energy - Chef makes the food we eat in the plane
Lysosome/Trash Bin
Lysosome removes waste The lysosome is like the bin. The bin is used to get rid of the waste.
Vacuoles/Food Storage
Vacuole in cell is a storage area to store nutrients. The food storage is used to store the food.
Cytoskeleton/Body of an airplane
forms a shape for the cell The body of an airplane forms a shape of an airplane
Golgi/Trolley
- Golgi apparatus is like a the trolley that delivers food, drinks, and merchandise in the airplane. Golgi apparatus and trolley are alike.
During this term, I learned about cell in Biology. I learned about the organelles of the cell. I learned about its function and where is it located. I also learned about how the cell works. My first task was making a website and put information about the cell theory. Other than learning about the cell’s function, I also learned about the cell theory. After learning about the cell theory and cell function, I was given a task to form a group and spread a warning about a specific disease. After making a group, we divide our jobs in a form of group work. My job is communication. Basically, the role of communication is to inform information from the teacher. Also, to bring to gather the group and start a discussion. After deciding jobs, we pick a disease. My group chose Tuberculosis. Since it’s one of the oldest and also one of the deadliest disease. Then, we were told to make a proposal. I faced a lot of difficulties this term. Personally for me, some of the topic are very confusing. It takes time for me to understand about the topic. But, anything is possible as long as I keep on reviewing what I have learned. Also, one thing that has been bugging me and put me in a hard time is my laptop. My laptop was broken and took so long to fix it. What should I do next time? First of all, I need to manage my time more wisely. I need to change my bad habit which is procrastinate. I always procrastinate when it comes to working on school works. Procrastination makes me stressed out because when I procrastinate there are lots of school works being delayed. So, when it the due date is near, I get stressed out. I should not procrastinate next time. Second, I should review my notes, so that I can understand more about the topic and not forget what I have learn in class. Lastly, I should be more careful taking care of my laptop.
Reflection biology
Reflection Biology Term 2
1. What did you learn in detail in term 2? In term 2, I learned a lot about human body system. I learned about mitosis, meiosis, pedigree, punnett square, DNA replication, RNA, translation, transcription and also human body system. Genetics is the study of how living things pass on characteristics or traits from generation to generation. I also learned about phenotype and genotype. The way an organism looks and behaves is called phenotype and the all combination of an organism contains is known as it genotype. Eye colors, height, hair color, etc is the example of a phenotype and TT or Tt is the example of a genotype. Also, there is a punnet square. In order to make a prediction of a possible genotype and phenotype of a something, we use a punnet square. Punnet square is a diagram of the possible genotypes of an offspring from a cross or breeding. Another topic I learned this term is Meiosis. What is meiosis? Meiosis is the process by which gametes with half the number of chromosomes are produced. Another topic I learned this term is about DNA. What is DNA? DNA is a molecule that contains all of the genetics of information to build an organism. The four main bases includes Adenine, Thymine, Cytosine and Guanine. While RNA, is something similar to DNA. RNA also contain genetic informations. However, the difference between DNA and RNA is DNA is double stranded while RNA is a single stranded. Another topic I learned this term is about protein synthesis. What is protein synthesis? protein synthesis is the process of regulating the cell’s activities with protein. Last but not least, this term I learned about the 11 human body system which are integumentary system, muscular system, skeletal system, nervous system, circulatory system, lymphatic system, respiratory system, endocrine system, excretory system, reproductive system and digestive system. All these organs/system in our body work together in order to keep us healthy and active.
2. What was the most interesting thing that you learned in term 2? I learned a lot of topics in this term’s biology class. But, for me the most interesting topic I learned is in biology class is human body system. Why is this interesting for me? its interesting for me because I can actually understand about each and every organs in our body. It is very interesting how it can all work together. How can it all be connected to keep our body in balance.
3. What was hard about the topic that you learned in term 2? The hardest topic I learned is pedigree. Why? because personally for me, pedigree is very confusing. Pedigree is hard for me to learn. Maybe, I should’ve learned more about pedigree in order to understand deeply about pedigree. Since, pedigree is very hard and confusing to understand.
4. What could you have done better in term 2? In term 2, i should have learned more about the topics that I’m learning. In order to understand more and can do better in my summative. Because, I’m not quite satisfied with the result of my summative. I should have learned more about the topics. I’m planning to be more active in learning the topics in my biology class.
tERm 2
VOCABULARY BIOLOGY TERM 2
Taxonomy: has to do with classifications about species in earth
Biodiversity the study of life in a ecosystem
Six kingdoms a classification of a organism
Dichotomous key The identification of items in the natural world.
Classification of Animals dividing animal species by the characteristics
Food web a diagram that shows the
Biome a community occupied by animals and plants.
Ecosystem interaction between the animal and the environment
At the beginning of our planning of our terrarium, we wanted to have both water area and land area. Since, the turtles needs water area for them to swim and cool off. But, in the process of making the terrarium, many problems occurred when we made the water area for the turtles. The water was constantly contaminated and getting very toxic and dirty for the fishes and the turtles to swim there. So, we decided that we don’t need the fishes because we also decided to replace the water area with land area. But, we didn’t forget to put a small pool for the turtles to swim there. We also provide many foods and plants for the turtles and also earth worms to keep the soil fresh. Then, we left the terrarium alone for 7 days, until the science fair. After 7 days, we checked on our terrarium and we found out that one of our turtles died. Our group predicted because the turtle got lack of foods, because the other turtle ate the majority of the food in the terrarium. However, the other turtle is fat, big, and healthy. So our terrarium worked according to plan B. Our terrarium even have a water cycle in it. Because we provide a small pool and we put the terrarium outside. The water evaporates from the heat and creates an water cycle.
TERM 4
Evolution
In the terms of biology, evolution is the change of the characteristics of a species over generations. Evolution relies on the process of natural selection. The theory of evolution is based on the idea that all species are related and gradually change over time. Some of these characteristic give an advantage or a benefit to the specific individual over other individuals which they can then pass on to their offspring. People create their own theories and their own opinions about evolution. Charles Darwin is one of the example of the few peoples. Charles Darwin made a theory about evolution. His theory is every organism changes over time and that modern organism is descended from ancient organism. He made his theory based on his research. His method of research is observation. Darwin went around the world Britain, South America, Equator, Chile, Australia, Indian Ocean, Africa, then went back to Britain. To prove his theory, he collected many fossils and analyze the type of animal of the fossil. Later, he found out that these animal fossils are different from what animal is alive today. From here, he can see that organism do changes over time.
Evolution happens through the generation is because there is a change in the DNA or the gene as the gene passes from one generation to the next. Some of the changes affects the animal's appearance, behaviour, or how the body works. Sometimes, an animal with a new characteristic survives better than an animal with the old characteristics. Then, that animal is likely to have more offspring. The offspring will inherit the new version or the new characteristics of the gene and start to pass it on again.
What is different between a fact and a theory? A theory is a conceptual framework that explains existing observations and predicts new ones. A theory is similar to an hypothesis, it also similar to a prediction. While on the other side, a fact is something that is proven to be true. Certain things can be called a fact when it has prove, a logical and explainable prove.