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In our class of Biology we have seen the topic “Pathogens”. Then our teacher told us to do a presentation for adults explaining this topic. Here is the presentation. I worked with Tomas Borda, Juan Lutowicz, Joaco Venini and Bauti Olaizola.
In our Biology class we have studied our last topic of “Digestive System” that is diarrhoea and cholera. After watching a video about this topic we had to answer the following questions. I work with Juan Lutowicz.
1) Name signs/symptoms caused by cholera.
Diarrhoea, vomiting, weaknessies and getting dehydrated are the signs.
Feeling sick is the symptom.
2) State ways in which the bacterium spreads in the village.
The first way of how the bacterium spreads in the village is by the spreading of the river, through flies that transport the bacteria, throught dirty hands and throught food not washed.
3) What is diarrhoea?
Diarrhoea is when faeces are discharged from the body, usally in liquid form.
4) How does the cholera bacterium cause diarrhoea?
It produces a toxin that attaches to the wall of the small intestine and affects the villi and makes it secrete chloride. Which causes water from the blood to move into the lumen by the process of osmosis.
5) How did the boy treat his father?
The boy treated his father by filtrating and boiling water at 100ºC to kill the bacteria. Then he gave his father the pure water with half of a teaspoon of salt and 6 of sugar that contained all the minerals that he needed.
6) Name the different actions which the boy taught to the people in the village to prevent the disease.
The ways to prevent the diseaseare:
- Washing your hands before eating and cooking;
- By filtrating water;
- By boiling water to kill the bacteria; and
- By building toilets of at least 20 meters far of the river.
In our Biology clas we have been studying “Human Nutrition”. In this new topic we have learnt what is diet, a balance diet and what defficency disease you have if you don’t have balance diet. Here is a presentation about human nutrition.
In groups we have made a Document with the different types of defficency diseases.
In Biology we have been studying the movement in and out the cells. Today experiment consisted on cutting strips of potatoes and soaking them in distilled water and a concentrated solution for 24 hours. Then we took another strip of potatoe that was not soaked in anything and then compared them. I work with Flor Araya and Rochi Hartmann. This are our results.
Potatoe in distilled water: This was the stiffest and least flexible potato because it absorbed water, therefore it swelled and became firm.
Natural potato: This potato was less stiff but more flexible than the one soaked in distilled water.
Potato in concentrated solution: This was the least stiff one of all and the most flexible.
In our Biology class we have started seen our new topic: Specialisation of cells. We have seen seven different tipes of cells. Ciliated cell, root hair cell, xylem vessels, palisade mesophyll cell, nerve cell, red blood cell and sperm and egg cell.
Adaptation: It has a layer of tiny hair called “Cilia” which can move and push mucus from one place to another. The “Mucus” can transport trapped dust and microbes when it is pushed by the cilia.
Root Hair Cells
Adaptation: Plant roots have root hair cells for absorbing water and mineral salts.
Adaptation: Transports water and supports the plant. The cell has no cytoplasm (so water can pass freely), no end wall (so that many cells can form a continuous tube) and walls strengthend with a waterproof substance called lignin.
Palisade Mesophyll Cells
Adaptation: Some plants have palisade mesophyll cells that contains chloroplasts to produce photosynthesis.
Adaptation: Animals have nerve cells to transmit information in the form of electrical impulses.
Red Blood Cells
Adaptation: Transports oxygen from the lungs to the tissues where aerobic respiration occurs. The cytoplasm is filled with the pigment haemoglobin, which carries oxygen. The cells have no nucleus, leaving more space for haemoglobin, and they are very flexible (They can be forced through even the narrowest of blood vessels).
Sperm and Egg Cells
In testes are sperms cells and in the ovaries are egg cells that contains the genetic material to trasnmit genetic information from the parents to the
The sperm has a tail which produces swimming movements to go to the egg cell.
In our Biology class we have learnt more about living organisms and their characteristics. Our teacher told us to work in pairs about one organism, in my case was a bird, ilustrate it and determine from which class it was. I work with Agustin Segura.
1. Construct a table to compare the characteristic features of animals, plants, fungi, protoctists and prokaryotes: number of cells, differences in the cell structure, nutrition. You can upload the activity as a PDF file on your blog.
2) Create an infographic showing the external features only of the following animals. Make it visual, so choose any animal which represents the class. For e.g. from the class reptiles, snake.