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Biology chapter 3
Summary of Respiration in living organisms
Cellular respiration
it is the process by which energy is extracted from the chemical bonds in the food molecules,
Structure of ATP Stages of glucose Oxidation
1- Glucolysis occurs in cytosole
2-Krebs cycle occurs in Mitochondria
Q. GR.. Krebs cycle does not need Oxygen
Ans. Because oxidation of organic molecules takes place by the release of electrons, The released electrons & protons are received directly by the Co-enzymes NAD+ & FAD.
Oxidative Phosphorilation
It is the formation of ATP molecules from ADP molecules by using the energy that released when the electrons descend step by step down the energy levels of the Cytochromes during the electron transport .
3-Electron transport occurs in Mitochondria Comparison between Burning sugar in the living cells and in Air Look at your notes Respiratory system in man [size=3]The Structure Of The Human Respiratory System
Structure and adaptation of the trachea[/size]
a- It is supported by cartilaginous rings to prevent it against collapse
b- It is lined with cilia to reject foreign bodies.
c- It is divided into two bronchi which open at each of the two lunges.
The mechanism of human respiration (Ventilation of the lunges) o Inspiration (breath in) (Inhalation) o *
The intercostal muscles contract where the ribs move upwards and diaphragm muscle -
contract downwards, this leads to increase the size of chest cavity while its internal pressure decrease, this causes air to get into the lungs through the nose..
2- Exhalation or expiration
Comparison between inhalation and Exhalation After the end of expiration, a part of the air is always left in lungs. G.R.
This will help: a. In warming the new air coming to the lungs.
b. In protecting the alveoli against collapse.
√ The respiratory system in man plays an important role in the excretion of
500cm3 water,
CO2 & volatiles
A) An Exp. to prove that the non green parts of the plant respire
1- Dry seeds do not respire actively, so the volume of air in retort no.(1) not changes
2. Germinating seeds respire actively, in retort no. (2) but CO2 is not absorbed by NaCl
3. When germinating seeds in retort no.(3) respire, the released CO2 absorbed by KOH sol. So, the KOH rises up in the stem of the retort.
An Exp. to prove that the green parts of the plant respire
In 1. The green plant respires & releases CO2 to the air. This CO2 turns lime water to milky solution.
An experiment to prove alcoholic fermentation:
Observation:
1. Gas bubbles are seen on the surface of the solution
2. Lime water becomes turbid .
Conclusion:
Turbidity of lime water proves that CO2 has been evolved as a result of respiration of yeast.
Seeds of Angiosperms have the power to respire
anaerobically if they are kept under anaerobic conditions