AS Applied Science

What is combustion?

- The scientific word for burning

- The reaction when a substance burns and reacts with oxygen to produce heat light energy

Fuel + Oxygen ---->  CO2 + H2O

Equation for aerobic respiration:

Glucose + Oxygen ----> Carbon Dioxide + Water Vapour

Glucose = comes from the digestive system

Oxygen = Comes from the respiratory system

Waste Products = CO2 + Water (breathed out)

1. Compare and contrast combustion & respiration

Similarities

- Both cumbustion and respiration have the same products after the reaction.

Differences

- Combustion produces smoke whereas respiration does not

- Combustion is outside of cells but respiration is inside the body

Summary

- When supply of oxygen is high.

- Complete breakdown of glucose.

- Produces large amounts of energy.

- Generates energy by converting glucose + oxygen into carbon dioxide and water.

- Carried out for long periods of time.

- No oxygen debt is built up.

Roles of ATP

- Forms lysosomes necessary for secretion

- Activation of molecules lowers the activation energy

- Maintenance of body temperature

- Production of substances

- Maintenance, repair and division

- Active transport- change carrier protein in PM

- Movement- muscle contraction of filaments

- MEtabolism- Synthesis of Polysaccharide, Polypeptide, DNA/ RNA

Using Energy

Uses

- Activation of molecules, lowering the activation

- Production of substances

- Movement, muscle contractions

Muscles in action

- Some sporting activities rely more heavily ion aerobic than anaerobic respiration. In others the muscles produce the required energy by respiring anaerobically for most of the action

Oxygen Debt

Lactic acid produced during anaerobic respiration is transported to the liver. here it can be converted into a 3-carbon compound which can be used to produce ATP when the oxygen balance is restored.

Monitoring the Activity

You can monitor the effect that a period of activity has on the body by recording:

- breathing rate

- heart rate

- Blood oxygen Concentration

- Blood lactic acid concentration

1. What does ATP stand for?

A- adenosine triphosphate

2. What are the 3 main things that make up an ATP molecule?

A- Adenine, thymine Cystine or guanine- 3 phosphate groups

3. How many high energy bonds does ATP contain

A- Two

The Cardiovascular System

Definition

- Delivery of blood around the body through the heart, blood vessels + blood itsellf.

- The cardiovascular system also removes toxins from the body.

Key Definitions

A molecule of ATP is formed when 3 phosphate groups are attatched to a molecule called adenosine. Energy is required to attatch the phosphates particularly the third. Respiration provides this energy. ATP is produced during respiration. When ATP is broken down e.g. ATP to ADP, this energy is released. ATP is used as a means to transfer energy from one process to another.

Uses of ATP

- muscle contraction

- swimming of sperms

- nerve impulse transmission

- the seperation of chromosomes during nucleur division

- the update + loss of ions & other particles

- Active transport

What is AMP?

One form of AMP is an important messenger molecule in the human body.

What is a Hormone?

A hormone is a chemical message sent from the brain.

what causes the changes in the rhythm of the heart?

excersise causes the change in rhythm so the extra oxygen needed for respiration is pumped around the body. Hormones can also change the heart rate as well as nervous control. a parasympathetic nerve called the vagus, delivers impulses to the SAN + AVN

What triggers a change in Heart Rate?

- increased respiration in muscles

- increased requirement for O2 + removal of CO2

- increased CO2 in blood decreases pH

- detected by chemoreceptors located in the cardiovascular centre in the brain.

- this causes a nerve impulse to be sent down the cardial accellorator nerve.

PQRST

'P' wave- Represents the impulses passing from the SAN to the AVN through the walls of the atria.

QRS-  Shows the electrical impulses travelling down the bundle of his & perkinje fibres.

'T' wave- Occurs as the ventricles recover.

Human Ventilation System

Cartilage:- the function of cartilage is to prevent collapse & retain flexibility, keep airwaves open. they are found in the trachea for example.

Goblet cells:-the function of goblet cells is to secrete sticky mucus & are found in the airways of the human ventilation system.

Cillia:- causes the airway to become narrower. this restricts airflow. usually found in the trachea, bronchus + large bronciole.

Feature:

Ribs + Sternun- Inhalation raised by contraction of external intercostal muscles. Exhalation lowered by gravity + contraction of intercostal muscles.

Diaphram- inhilation pulled down by the contaction of muscle fibres in the diaphram. Exhalation diaphram moves up due to contraction of abdominal wall muscle elastic recoil for resistance.

Features of the Alveoli for Gas Exchange

1) Large surface area

2) Thin

3) Moist

4) Permeable- O2 + CO2 can move in and out.

5) Good blood supply

6) Difusion gradient

7) Red blood cell felxible

8) Thin- short diffusion pathway

**Oxygen is transported around the blood stream in the red blood cells**

Nutrients cush as glucose, amino acids , fatty acids and glycerol are transported around the body in the blood stream.

They are added by diffusion, faciliated diffusion or active transport depending on the size of the molecule

Transport of carbon dioxide

carbon dioxide is released from respiring tissues. It must be removed from these tissues + transported to the lungs. It is transported in 3 ways.

- about 5% is dissolved directly into the blood plasma

- about 10% is combined directly with haemoglobin to form a compound called carboxihaemoglobin.

- About 85% is transported in the form of hydrogen carbonate ions (HCO3)

- Blood Temperature

- Blood Pressure

- Breathing Rate

- Heart Rate

- Blood Glucose

- Blood Cell Count

* Why do doctors take blood sample?

A- To identify, confirm or reject possible conditions

* What are the 3 possible causes why blood count is decreased with anaemia?

A too few blood cells are being produced, some of them produced may be destroyed, by blood loss (bleeding) having taken place.

- How are blood counts determined?

A- by using an automatic analyser

- What is a levcocyte?

A- levcocytes are white blood cells, there are several different types including neutrophils, lymphosytes, monocytes and basophils.