1. Materia: Biology Senior 3
Profesora: Ma. Magdalena Ravagnan
Contenido nodal: Maintenance of the organisms
TERCER TRIMESTRE
Fecha de presentación: February 2014
A- Heart and circulation
1) Fig. 8.1 shows a diagram of a section through the heart.
(a) On Fig. 8.1:
(i) label an atrium; [1]
(ii) label the pulmonary vein; [1]
(iii) shade in the chambers that contain deoxygenated blood. [1]
(b) Name the blood vessel that delivers blood to the muscles of the heart.
……………………………………………………………………………………………………………….[1]
(c) State two preventive actions a person could take to reduce the chance of a heart
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2. B- Respiration
1) Define the term respiration.
2) During exercise muscles need to obtain energy even when there is no supply of oxygen.
a- Name the type of respiration in muscle cells during exercise. : ………………………………………..
b- Write the formula for the respiration named above, in words.
…………………………………………………………………………………………..
c. During respiration in yeast, other products are produced. Write the formula and underline the products.
3 ) Why do you think your breathing rate and heart rate stay high for some time after completing a spell of vigorous
exercise?
C- Gas exchange
a- Explain the role of the following structures during exhalation
Diaphragm: ………………………………………………………
Intercostal muscles: ……………………………………………….
Volume of rib cage: …………………………………………………….
Pressure in lungs: ……………………………………………………………
b- i- Name the gas exchange surface in humans.
ii- Explain what causes the oxygen and carbon dioxide diffuse for gas exchange.
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