Category Archives: 4AC2016

Experimentos de Presión

En Física estamos aprendiendo sobre la presión. Eduardo nos pidió que hicieramos dos experimentos: el del huevo y el del agua en un vaso tapado por papel.

En el primero lo unico que se necesitó fue un huevo. Se aplicó fuerza en las puntas mas angostas y no se rompió.

En el segundo se llenó un vaso con agua hasta el borde, se lo tapo con un papel y con cuidado se dio vuelta y vimos que el agua no salió.

Este es el video mostrandolos:

Endocrine System

The new topic in Biology is the Endocrine System and we were to do the activities on Male’s blog:

  1. Hormone: chemical substance produced by a gland, carried by the blood, which alters the activity of one or more specific target organs.
  2. Search in the internet a picture which shows the glands which secrete  hormones in the human body.

What hormones secrete each gland:

Adrenal gland: Adrenaline
Pancreas: Insuline
Testis: Testosterone
Ovary: Oestrogen
Thymus: Thymosin
Thyroid gland: Thyroxine and calcitonin
Pituitary gland: Growth hormone
Pineal gland: Melatonin

3. ADRENALINE. State the effects of adrenaline. Chose a picture which shows a situation in which adrenaline is secreted. Explain.

Adrenaline is when you are frightened, excited or keyed up. There your brain sends impulses along a nerve to your adrenal glands, and these secrete adrenaline into the blood. The main effects of adrenaline are: Your hearts beats faster, your breathing rate increases, your pain body’s ability decreases and it causes a noticeable increase in strength and performance.

“The Border Builder” by Carol Rumens

In Literature with Luz, Jose and Delfi, we worked on “The Border Builder” by Carol Rumens and wrote up a questionnaire for our peers to answer later on. Here’s ours:

1. What does the writer think ahout borders?

2. Explain the ending of the poem.

3. Who is the persona talking to?

4. Explain what effect repetition has on the reader.

5. Explain the following quotation: “My bricks, O my genuine bricks Made of my genuine blood!”

6. How can you relate the poem to the present day?

Extracting DNA

Today we went to the lab and did an experiment on extracting DNA. This is how it got carried out:

To extract DNA from natural products

to observe the fibrilar structure of DNA.

Plastic cups – onion, banana

test tubes – Distilled water

knife – detergent

sticks – salt

a beater – ethanol

1- Cut the central part of the onion into cubes.

2- Add 3 tsp of detergent and 1 of salt in a plastic cup, and pour distilled water up to the top.

3- Mix this solution with the pieces of onion.

4- Beat all the mixture at high speed for 30 seconds.

5- Filtrate the liquid with a coffee filter.

6- Fill ¼ of a test tube with the filtrate.

7- Add some pieces of banana and mix thoroughly.

8- Add the same volume of ethanol, carefully, so that it flows through the walls of the test tube and forms a layer on the filtrate.

9- Let it rest for 2-3 minutes until a cloudy area is formed between the 2 layers.

10- Extract a network of white fibres of DNA and place it on a Petri dish.

11- Add few drops of blue methylene and record your observations.

Record your observations!

a- Where in the cell is the DNA?
The DNA is in the nucleus.

b- What are the fibres made of?
The fibres are nucleotides joined together.

c- What is a gene?
A gene is a length of DNA that codes for a protein.

What is the DNA?
DNA is deoxyribose neuceic acid.