Chapter 9 : Respiration In Humans Flashcards
What is respiration ?
Oxidation of food molecules to release energy
State the uses of energy by the body (5)
Active transport
Synthesis of proteins and new protoplasm
Muscular contractions
Transmission of nerve impulses
Cell division
What is aerobic respiration ?
Breakdown of food molecules in the presence of oxygen, resulting in the release of a large amount of energy as well as carbon dioxide and water as waste products.
What does ATP stand for and how does ATP release energy ?
Adenosine triphosphate. Energy is release when. Phosphate bond is broken and ATP becomes ADP (adenine diphosphate)
Where does aerobics respiration occur ?
Mitochondria of all cells
What is anaerobic respiration ?
Breakdown of food molecules in the absence of oxygen, releases lactic acid and small amount of energy
Describe how O2 debt occurs in the body (4)
- Muscles contact vigorously during strenuous exercise
- Respiratory rate and heart rate increase to allow more oxygen to reach the heart
- When O2 intake cannot meet O2 demand, O2 debt results in anaerobic respiration to take over
- This results in lactic acid accumulation in the muscles
What happens during rest after strenuous exercise ?
- Breathing rate continues to be fast for some time to repay O2 debt
- Lactic acid is transported to the liver
- Some are then oxidised to release energy
- Energy is then used to convert remaining lactic acid to glucose
Describe the passage of air through your respiratory system ( 6 )
Nasal passage
Pharynx
Larynx
Trachea
Bronchus
Bronchiole
Alveoli/ alveolus
State the function of gland cells and ciliated cells and where they are located
Located on the inner walls of the trachea and bronchi
Gland cells secrete mucus which traps duct and bacteria in the air channeled to the lungs
Ciliated cells have cilia which help to sweep up trapped particles upwards into the pharynx
State the 3 adaptations of the alveoli
- Well supplied with blood capillaries —> ensure efficient exchange of gases
- Thin film of moisture between alveoli and capillaries —> allows gases to dissolve and diffuse into the blood stream
- One cell thick —> wall of alveolus is one cell thick to reduce distance between the capillaries and the alveolus and reduce time taken for diffusion
How is CO2 transported in the blood ? (3)
- CO2 entered the RBC in the blood stream
- CO2 molecules react with water in blood to form carbonic acid, catalyse by an enzyme known as carbonic a hydrate
- Carbonic acid is then converted into hydrogen carbonate ions which would diffuse out of the RBC into the plasma
Name the 2 sets of muscles found in between the ribs
External and internal intercostal muscles
Describe the process of inspiration/ inhalation (3)
- Diaphragm contracts and flattens down
- External IM contracts , internal IM relaxes —> rib cage raised upwards and outwards
- Thoracic volume increases, air is drawn into lungs
Process of expiration/ exhalation (3)
- Diaphragm relaxes and arches upwards
- External IM relaxes, Internal IM contracts, diaphragm moves inwards and downwards
What is the stimulus for breathing ?
CO2
State the effects of Nicotine, CO, irritants and Tar on your body
Nicotine:
- addictive
- makes blood clot easily
- increases risk of heart diseases
CO
- Decr ability of RBC to transport O2
- incr rate of fatty deposition on arterial walls
- incr rate of atherosclerosis
Irritants
- Paralyse cilia linings in the air passages
- incr risk of chronic bronchitis and emphysema
Tar:
- Carcinogenic
- paralyses cilia linings
- reduces efficiency of gaseous exchange
What is chronic bronchitis and what are some symptoms ?
- Epithelium lining becomes inflamed
- Excessive mucus secretion
- Cilia lining in airways are paralysed
Symptoms
- breathing difficulties (blocked airways)
- persistent cough ( attempt at clearing blocked airways )
What is emphysema and what are the symptoms
- Partition walls of the alveoli break down due to violent coughs ( SA of alveoli Decr, reduces efficiency )
- Lungs lose elasticity and become inflated with air
Symptoms
- breathing difficulties
- wheezing
State the purpose of the C shaped ring of cartilage below the trachea
- Support the trachea and ensures that the trachea is always open
