Archivo de la categoría: biologia

Some classes ago, our bIology teacher, told us to create a model of the urinary system, using trash, as the image(taken from our teacher’s blogs) shows. The purpose of this, was that we shouldn’t need to buy things and that this trash materials, would have another use. In this project, I’ve worked with Matías Ripoll.

As the image, taken from our teacher’s blog, shows we used cans of drinks covered with red paper, to represent the kidneys, as they´re red. Moreover, ureter and urethra were presented in our project with strings. Also, the renal artery and the aorta were made by us with red straws, while the renal vein and the vena cava were made with blue straws. Finally, we use a plastic sac to represent the bladder.


As a last step, we should include each function, of each organ of this system. And this is what we wrote:



  • Kidneys: The kidneys are two bean-shaped organs found on the left and right sides of the body in vertebrates. The kidneys receive blood through the renal artery. The blood reaches the kidney and this one, together with its components(millions of nephrons) start to work. The wastes, such as urea, salt, water and minerals which weren´t extracted from food, are removed from blood and converted by the kidneys (and functional nephrons inside them) into urine, which is drained down a tube by the name of ureter.
  • Nephron: The nephron is the tiny structure in your kidneys which helps to filter your blood. Each of your kidneys contain more than a million of these structures. It removes the wastes(urea, salts, water, minerals) from blood and converts them into urine, which is later passed through the ureter into the bladder.
  • The ureter: The ureter is a large tube that carries urine from the kidney to the urinary bladder. There are two ureters, one attached to each kidney. In the abdomen, the upper half of the ureter is located and the lower half is situated in the pelvic area. In adults, the ureter is about 10 to 12 inches long and it always has thick walls composed of a fibrous, a muscular, and a mucus coat, which is able to contract.
  • The bladder: The bladder is an expandable muscular sac located in the lower abdominal area near the pelvic bones. This one stores and keeps urine before it is excreted out of the body through the urethra. The bladder contracts when it is empty. When empty, the bladder’s muscle wall becomes thicker and the entire bladder becomes firm.
  • The Urethra: Throughout the urethra, the urinary bladder and the outside of the body are connected. Once the bladder becomes full, urine flows through the urethra and leaves the body. The urethra is more than just a urinary duct; it also serves as a conduit for semen and sperm during sexual acts in men.
  • The renal veins: There are two renal veins, the left one and the right one. They branch off the inferior vena cava and drain oxygen-depleted blood from the kidneys. As they enter the kidneys, each vein separates into two parts. The posterior veins drain the posterior section of each kidney, while the anterior veins do this same thing but in the front part. These veins also drain blood from the ureter, which carries urine away from the kidneys to the bladder.
  • The renal artery: The renal artery is one of the two blood vessels which leave the abdominal aorta and enter the kidneys. The renal artery enters through the hilum, and once it does this, it splits into two main branches. These ones each then split into numerous smaller arteries called nephrons, which deliver blood to different areas of the kidneys.
  • The inferior vena cava: The inferior vena cava is a large vein that transports de-oxygenated blood(most of the oxygen has been removed by tissues, and therefore the blood is darker) to the heart from the lower body(legs and lower torso).
  • The abdominal aorta: The abdominal aorta is the largest artery in the abdominal cavity. As part of the aorta, it is a direct continuation of the descending aorta and branches to form the major arteries of the abdomen. It provides blood to the organs and tissues of the abdomen, pelvis, and legs.



Finally, this is our labelled model:

Respiration + Gas Exchange

Activity 11,3 Book Page 143

A1: it is important to boil water to drive off any dissolved water

A2:Water has to cool down because, if not, the yeast would die

A3: the paraffin’s function is to isolate yeast from outside’ air

A4:in the tube containing living yeast, the substance will be cloudy, as the yeast will respire. However, in the tube containing dead yeast, the substance will be clear, as yeast are not resiring.

A5: the new substance that will appear in the living yeast test tube is alcohol, as it is the product of annaerobical respiration in yeast.

A6:  to be continued…


Biology Notes-Chemicals of Life


Chemicals of life        

-What all living organisms are made of   
.Carbohydrates (C-H-O)
.Lipids (C-H-O)               
.Proteins (C-H-O-N-S [Sulfure])              
-All of them are made of 3 atoms:       

-Monosacaryzed (one sugar) (glucose),  disacaried (two) (sacrose) and pollysacarized (more than two) (cellulose)                 
-In common-very soluble in water
.Main source of energy       
.Storage of food  (plants-starch / animals-glycogen)


-Twice the amount of energy is onbtained from lipids than from carbohydrates
-two types:

.Oils-are liquid and come from plants
.Fats-are solid and come from animals


-From froots and vegetables
-To make muscle tissue, antibodies and other new cells
-Made of aminoacids                
-In blood-plasma proteins-made to keep liquid inside blood
-Aminoacid: amino-acid
-Enzymes are all proteins, they have both functional and structural functions
-Ej of a functional enzyme: Amylase in saliva to break down large molecules into small molecules by cutting down their bonds

What we need for a balanced diet:

-Protein (energy and structural functions)
-Carbohydrates (energy)
-Lipids (fats and oils for storage of energy or structural functions)
-Fibre or roughage to scrape the inner part of the intestines for them to keep working well)
-Minerals like calcium or potasium

Respiration… Not breathing!!

Respiration takes place in mitochondria, which is inside the cytoplasm

  • Mitochondrion singular, Mitochondria plural
  • Most of chemical reactions happen in mitochondria
  • Mitochondria⇾double membrane
  • Receives molecules like O2, H2O, CO2, C6H12O6, etc, and releases energy for metabolism. Glucose-main source of energy
  • Number of mitochondria in a cell depends on the energy the cell needs
  • Aerobic respiration: C6H12O6 (glucose)+ 6O2  (oxygen) = 6 H2O (water) + (number of carbon dioxide molecules) ⇽ 6CO2 + 38E (Energy ⇾ ATP molecule). If you switch the ecuation, you get the ecuation of photosythesis
  • The number of atoms that comes in the mitochondria will be the same when it comes out.
  • Respiration ⇾ Chemical reaction, releases energy from food we inhere and from oxygen we breathe
  • Functions of respiration (provides energy to):
  1. Muscle contraction
  2. Cell division; to repair damaged tissues and to grow
  3. Making of proteins; gives energy to rybosomes to bring together amino acids to form long chains
  4. Active transport or movement
  5. Transmitting nerve impulses
  6. Maintenance of body temperature (t°)
  • Mitochondria ⇾ through enzymes it breaks out glucose and oxygen molecules, and then it makes water and carbon dioxide, and releases energy ⇾ the energy contained in the glucose molecule is much more than the energy the mitochondria needs to form H2O and CO2 molecules, therefore, there will be more energy, that will be used for other functions.
  • Aerobic respirarion: respiration with oxygen
  • Anaerobic respiration: respiration without oxygen, used when we need more energy, therefore, we get less energy, as this type of respiration produces latic acid (C3H6O3) and much less energy. Ej: when we do exercise
  • ATP (adenosintriphosphate)molecule: way in which energy is kept. Very unstable molecule,  phosphates always separating from each other, as a consequence, energy is released
  • In anaerobic respiration which happens in yeast, from 1 molecule of glucose, we get 2 C2H5O2 (ethanol) and 2CO2
  • Oxygen debt: we need oxygen when we stop doing exercise to destroy latic molecules
  • From 1 glucose molecule, you get 38 molecules of ATP

States of Matter Basics by Bautista Buljevich and Tomás Braun


Using the simulation, try to change the phase of water. For example, change liquid water to solid or gas.

Resultado de imagen para differences and similarities between solids liquids and gases on a molecular level

  • Gas: This state is present when water reaches the boiling point (100 Cº), water starts evaporating. When this happens, water molecules start to separate from each other and disperse, constantly moving
  • Liquid: This state is present when water is in a warm temperature. As it is neither too hot nor too cold, it will not disperse in the air or be all too close together. However, it will have the force to stay together.
  • Solid: This state is present when water is in a too cold temperature. When this occurs, water molecules are too close together, always in a fixed position, therefore, there is a little space between them and are not able to move from their place.

Questions on Chapter 19 of the biology book

Tuesday 4th

Matías Ripoll and Tomás Braun

Make an evaluation on the chapter. Include between 7-10 questions NOT including any of the end of Chapter 9 or the ones found along the chapter.

1) Make a comparative chart between continuous and discontinuous variation.

2) What is mutation and what consequences does it bring?

3) What can you do to avoid mutation?

4) Why can we say that an animal or a plant that is well adapted to its environment is much more likely to survive than one that is not?

5) Which is Charles Darwin’s theory and what does it state?

6) Explain the differences between natural selection and artificial selection.

7) Which are the causes of genetic variation?

8) What was Charles Darwin’s evidence to prove his theory?