B1.2-Respiration and the Respiratory System in Humans

Plants make amino acid from sugar,nitrates and other nutrients.

Amino acids-Larger molecules-Proteins.

Energy used by animals to enable muscle to contract-Animals can move.

Mammals/birds-Keep body at a steady temperature.

Respiration is used to do this when surroundings are cool.

Aerobic respiration is the form of respiration which uses oxygen.

Glucose+Oxygen-Carbon Dioxide+Water (+ Energy).

Energy is shown in the brackets because it is not an substance.

Glucose and oxygen are used.

Co2 and water are produced as a waste product.

Aerobic respiration happen constantly in cells of animals and plants.Most reactions happen in mitochondria,tiny objects inside the cytoplasm of the cells.

Reactions controlled by enzymes.

Not enough oxygen-Exercise-Use anerobic respiration-Energy.

Incomplete breakdown of glucose-5% of energy released by aerobic respiration,per molecule of glucose.

Waste product-Latic acid rather than Co2 or water.

Glucose-Lactic Acid (+Little Energy)

Muscles become fatigued (tired) during long periods of vigorous activity-Stop contracting efficently-Build up of Latic Acid in muscles from anaerobic respiration.

Latic Acid is removed from muscles by blood flowing through them.

Less energy is released in anaerobic respiration than during aerobic respiration.This is because the breakdown of glucose is incomplete.

Anaerobic respiration produce oxygen debt-Amount of oxygen needed to oxidise Latic Acid to Carbon Dioxide and water.

Existence of oxygen debt explains why we breath deeply and quickly for a while after exercise.

C8H12O6+6O2 - 6CO2+6H2O.

Inhale-

More oxygen to create energy.

Less Co2.

Exhale-

More Co2 produce as a waste product of energy production.

Less oxygen as it has been used in respiration.

Gas exchange takes place by diffusion in the alveoli within the lungs.As a result the composition of inhale and exhale air is different,

Inhale-

Oxygen-21%

Co2-0.04%

Nitrogen-79%

Exhale

Oxygen-16%

Co2-4%

Nitrogen-79%

During exercise muscles work harder-Need more energy-Rate of respiration increases.

More oxygen is needed and more Carbon Dioxide is made-Breathing rate increases.

What type of molecules control rate of reaction in cells?-Enzymes.

What do plants use the energy from respiration for?-Transport,protein.

Give two changes that happen when you exercise?-Temp,Breathing.

Why so athletes "carb load" before a race?-So sugars are available.

What is fermentation?-Anaerobic respiration.

Why do muscle cells have lots of mitochondrias?-Energy.

Why does anaerobic respiration release so much less energy than aerobic respiration?-Glucose isn't broken down completely.

Breath in-

Intercoastal muscle is between the ribs.

Moves the ribs up and out.

Diaphragm muscle contracts and moves down.

Volume of air inside the chest increases.

Decreases the pressure inside the chest.

Air pressure outside the chest is higher so air entres the lungs.

Breath out-

Intercostal muscle relax.

The ribs move down and in.

The diaphragm muscles relax and move up.

The volume of air inside the chest decreases.

Increases pressure inside chest.

Pressure outside chest is lower so air leaves the lungs.

Image:Respiratory System.

Image/Information:Bell Jar Experiment

Good Luck.