In our Biology class, our teacher, Marcela, showed us a video and asked us to take down notes on it to then prepare a presentation on it.

This was the video she showed us:


And this is the presentation I made:


In addition, we had to think of 10 questions on the topic:

  1. Name two important roles that water plays in the human body
  2. Explain how the body reacts to dehydration
  3. What does the intake of water depend on?
  4. What is the difference between hydrogen bonds and polar bonds?
  5. Why is water a universal solvent?
  6. Why is a high tension surface formed?
  7. Water can abosrb a large amount of heat before changing its chemical state thanks to what?
  8. When in low temperatures, how do hydrogen bonds react?
  9. Name two symptoms of overhydration.
  10. How much water does a cell contain?

Homeostasis: Control of Blood Sugar Levels

In our Biology class we have been studying Homeostasis, and in order to understand how it works, in terms of the control of blood sugar levels, our teacher, Male, asked us to make a flow chart showing what happens when the levels of glucose in blood increase and decrease.

This is the flow chart I made:


NEGATIVE FEEDBACK: the negative feedback control system responds when conditions change from the ideal or set point and returns conditions to this set point. If the level of something rises, control systems reduce it again and if the level of something falls, control systems raise it again.



This is a comparison table between Diabetes type 1 and type 2:


GENETIC ENGINEERING: process to make sure there is enough insulin for everyone who needs it. It involves transfering artificially selected genes from one living organism to another living organism of the same species.

Endocrine System

This is an activity about the endocrine system. I worked with Gonzalo vazquez Avila and Joaco Venini.

Hormones: A chemical substance produced by a gland, carried by the blood which alters the activity of one or more specific target organs.


This is an image of the endocrine system and all it’s glands, including their respective functions (the hormone each secretes).

09 Endocrine Glands

The effects of adrenaline: prepares body to ‘fight’ (for a vigorous action), ability to feel pain decreases, strength and performance increases, awareness is hightened, heart rate and breathing rate increases, blood vessels in the skin and digestive system contract which makes you go pale, the pupils widen, and causes the liver to release glucose into the blood for the muscles to release energy from it (gives more energy) and use it to contract.


This is a picture of a situation in which adrenaline is secreted.


In this particular situation adrenaline is secreted because the people are frightened, excited or nervous which causes the brain to send impulses to your adrenal glands.

The Eye as a Sense Organ

In our Biology class we have been studying how the nervous system works. We studied the different receptros, and to study the eye as a sense organ our teacher, Male, asked us to:

1.Search in the internet a short video about pupil reflex:

2.Draw a flow chart explaining the reflex (stimulus, receptors, coordinator, effectors, effect and response).


The Nervous System

In our Biology class we started learning about the Nervous System. And in order to do this, our teacher, Male, asked us to take a look at these two sites:


Intel education

And do some activities on her blog:

1.a) 1- Lesson introduction; 2 – Your control centre, the key parts; 3 – The receptors; 4 – The neurones, nerve cells; 5 – Different types of neurones; 6 – Progress question; 7 – The central nervous system; 8 – Progress question; 9 – The nervous pathway; 10 – Example of a nervous pathway; 11 – Progress question.

1.b) SENSORY NEURONES: carry signals from receptors to the spinal cord and brain.


RELAY NEURONES: carry messages from one part of the CNS to another.


MOTOR NEURONES:  carry signals from the CNS to effectors.




1.d) The following video is an animation that shows how a synapse works:

The following video shows how a synapse works but also explains it:

A synapse is a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.

A nerve impulse arrives along the axon which causes a nerve-ending to release neurotransmitters. These chemicals diffuse across the synapse and into the next neuron.

Excretion and Kidneys

For our Biology class, our teacher, Male, gave us a worksheet with some questions for us to answer to revise the topic of excretion and kidneys.

1) a) Define the terms excretion and egestion

  • Excretion as removal from organisms of the waste products of metabolism (chemical reactions in cells including respiration), toxic materials, and substances in excess of requirements.
  • Egestion as the passing out of food that has not been digested or absorbed, as faeces, through the anus

1) b) The kidney is an excretory organ. It produces urine that contains urea. State where in the body urea is formed and what is formed from.

Urea is formed in the liver from excess amino acids.


In our Biology class we have been studying respiration more deeply. Therefore, our teacher, Male, asked us to work in groups and do the following activities. I worked with Luli and Bauti.

  1. The uses of energy in our body are:
  • for cells to contract our muscles in order to be able to move our body.
  • energy is used in reactions that produce different molecules
  • to build up larger molecules from smaller ones.
  • to  produce heat to keep their body temperature steady and constant.
  • cell division, to repair damaged tissue
  • to move substances across cell membranes up their concentration gradient (active transport)
  • to transmit nerve impulses



3. Anaerobic respiration produces an oxygen debt. This is the amount of oxygen needed to oxidise lactic acid to carbon dioxide and water. The existence of an oxygen debt explains why we continue to breathe deeply and quickly for a while after exercise.

4. This is a video that explains why breathing rate doesn’t slow down immediately after exercising.

In the minute 1:36 he begins to explain why and in the minute 1:50 he says that air also goes to muscles to help them recover afterwards.