B2 Flashcards
What does anaerobic respiration mean
Without oxygen- incomplete breakdown of glucose making lactic acid
When does anaerobic respiration occur
When you do vigorous exercise and your body can’t supply enough oxygen to your muscles
In anaerobic respiration glucose isn’t…
Fully oxidised
Formula for glucose turning into lactic acid
C6H12O6→ 2C₃H₆O₃ + 2ATP
What is meant by the term oxygen debt
Oxygen has to be repayed
- needed to remove waste build up of lactic acid in cells when oxygen didn’t get to muscles in time
What is bronchus
Plural for bronchi - two tubes down from trachea
Define Bronchioles
Progressively smaller tubes from bronchus
What is metabolism
All chemical reactions in an organism
Explain how lungs are adapted for gaseous exchange. Do not refer your answer to alveoli
Lungs are ventilated so that a new supply of air is constantly bought in
Describe how alveoli are adapted for gaseous exchange ( 6 marks)
- folded- increases s.a. (75 m²) let’s a larger volume of gases to be diffused at once
- thin membrane (walls are one cell thick) speeds up rate of diffusion by decreasing distance over which it occurs- creating short diffusion pathway
- rich blood supply, surrounded by network of capillaries - takes things from and to exchange surface efficiently
MAXIMISES GAS EXCHANGE RATE
Define thorax
Top part of your body separated from lower half by the diaphragm
Word equation for aerobic respiration
Glucose + oxygen ===== carbon dioxide + water
- energy is released
What is the formula for aerobic respiration
C6H12O6+ 6O2→ 6CO2+ 6H2O
How are arteries designed for their function (5)
Direction of flow:
Oxygenated or deoxygenated:
Pressure:
Wall structure:
Lumen:
- blood flows away from heart
- Oxygenated blood except pulmonary artery
- high pressure
- thick, elastic, muscular connective tissue for strength
- narrow Lumen- channel inside vessel
How are veins adapted for their function (5)
Direction of flow:
Oxygenated or deoxygenated:
Pressure:
Wall structure:
Lumen:
- blood flows towards the heart
- dexygenated except pulmonary vein
- low (negative) pressure
- thin, less muscular, less connective tissue
- wide Lumen with valves
Describe the 3 types of blood vessels
Arteries= carry blood away from the heart
Veins= carry the blood to the heart
Capillaries= are involved in the exchange of materials at the tissue
Define cardiac output
A measure of the volume of blood pumped by the heart each minute
Define stroke volume
A measure of the volume of the blood pumped from the heart each contraction (heart beat)
What is the equation of cardiac output
Cardiac output = stroke volume × heart rate
Q = (cm³/mm)
SV= (cm³/beat)
HR= (bpm)
What does SAN stand for
sino- atrial node
What does AVN stand for
Atrio- ventricular node
Function of SAN
Located near right atrium and stimulates atria to contract
Function of AVN
Located between ventricles and stimulates them to contract
What are pacemakers
Small group of cells located in muscular walls of heart that produces electrical impulses which stimulate surrounding muscle to contract , squeezing chambres of heart and pumping blood
The rate of the heart beating is very carefully and automatically controlled by…
Pacemaker cells within wall of right atrium
Why does the left ventricle have a muscular wall
Muscular wall of left ventricle is much thicker so it can pump blood more forcefully out of the heart and around the entire body via aorta
Describe coronary heart disease
Coronary arteries that supply blood to muscles of the heart get blocked by layers of fatty material build up
Causes arteries to become narrow so blood flow is restricted and there’s a lack of oxygen to heart muscle- can result in heart attack
What is the role of vena cava
Transport blood to lower part of body and drain deoxygenated blood to heart
What do red blood cells do
Job of red blood cells is to transport/ carry oxygen from the lungs to the rest of the cells in the body
How are RBC adapted for function
- shape is biconcave disc- gives large surface area for absorption of oxygen and flexibility of fitting into tiny capillaries
- no nucleus gives them more area to fit haemoglobin in- which binds to oxygen in the lungs and reverse happens in body tissue- breaks up to give oxygen to cells
- ## contain red pigmented protien called haemoglobin
Formula for oxygen and haemoglobin
Oxygen + Haemoglobin=====Oxyhaemoglobin
4O2+ Hb===== Hb4O2
What are the main symptoms of coronary disease
Chest pain
Heart attack
Heart failure
- not everyone however suffers same symptoms
What increases chances of getting CHD
Lifestyle factors:
- diet
- stress
- smoking