Mrs H bio 1 lungs and health studies

Question 1

how do the reactants for aerobic respiration enter the body?

Answer 1

glucose= intestine oxygen=lungs

Question 2

how do the products of aerobic respiration leave the body?

Answer 2

water= water vapour when breathing carbon dioxide= lungs

Question 3

where is the human gas exchange surface?

Answer 3

lungs

Question 4

what are the alveoli?

Answer 4

air sacs- site of gas exchange

Question 5

what adaptations do the alveoli have to make them effective at their function?

Answer 5

large surface area (as they are highly folded), high concentration gradient (maintained by a rich blood supply), thin diffusion distance (alveoli have a one cell thick epithelium)

Question 6

how does oxygen move through the lungs to reach the alveoli?

Answer 6

Trachea -> Bronchi -> Bronchioles -> Alveoli

Question 7

how does oxygen travel from the alveoli to the blood?

Answer 7

diffuses across the alveolar squamos epithelium -> then diffuses through the epithelium of the capillary -> then combines with haemoglobin in the red blood cells to form oxyhaemoglobin

Question 8

what is the trachea made out of?

Answer 8

rings of cartilage

Question 9

what is Fick’s law?

Answer 9

rate of diffusion= surface area x difference in concentration / diffusion distance

Question 10

what is squamous and what does it reduce?

Answer 10

thin squashed cell and these reduce the diffusion distance

Question 11

what is the process of inhalation?

Answer 11

external intercostal muscles contract causing the ribcage to move upwards and outwards, diaphragm contracts and flattens, thoracic cavity volume increases, pressure in thoracic cavity decreases to less than outside. active process- requires energy

Question 12

what is the process of exhalation?

Answer 12

external intercostal muscles relax, diaphragm relaxes and domes up, thoracic cavity volume decreases, pressure in thoracic greater than outside, air moves out of lungs down a pressure gradient

Question 13

what is the difference with forced exhalation?

Answer 13

same but in addition the internal intercostal muscles contract

Question 14

what happens when blood reaches the alveoli?

Answer 14

oxygen diffuses into the blood through the squamos epithelial membrane and at the same time carbon dioxide moves from the blood to the alveoli

Question 15

what happens to the blood after it is oxygenated at the alveoli?

Answer 15

it is circulated away from the alveoli by contractions of the heart, that move the blood away from the lungs and back to the heart to be pumped around the body

Question 16

what does the circulation of blood and air maintain?

Answer 16

a concentration gradient at the alveolar epithelium to ensure gases diffuse efficiently in either direction and do not reach equilibrium

Question 17

what is tidal volume?

Answer 17

natural breathing volume

Question 18

what is inspiratory/expiratory reserve?

Answer 18

extra volume required for a deeper breath

Question 19

what is residual volume?

Answer 19

air that remains in the lungs to prevent the collapse of alveoli

Question 20

what is vital capacity?

Answer 20

the maximum volume of air a person can expel From the lungs

Question 21

what is the equation for pulmonary ventilation?

Answer 21

ventilation rate x tidal volume

Question 22

what is the def for pulmonary ventilation?

Answer 22

the volume of air breathed In 1 minute

Question 23

what is the composition of gases in inhaled air compared to exhaled air?

Answer 23

inhaled= more oxygen, same amount of nitrogen
exhaled= more carbon dioxide, more water vapour, same nitrogen

Question 24

define ventilation

Answer 24

when atmospheric air is brought into or over the gas exchange surface.

Question 25

what affect does fibrosis have?

Answer 25

-Formation of scar tissue due to infection or exposure to certain substances -Scar tissue thicker and less elastic than normal lung tissue, meaning lungs less lilely to expand – tidal volume and FVC is decreased.​ -The rate of diffusion also decreases due to thicker tissue.

Question 26

what impact does tuberculosis have?

Answer 26

-Immune system builds wall around bacteria in lungs, forming hard lumps known as tubercles.​ -Infected tissue within tubercles die and gaseous exchange surface now damaged -reduces tidal volume, causing patients to breathe faster.

Question 27

what is asthmas impact?

Answer 27

-Airways become inflamed due to an allergic reaction (pollen/dust).​ -Smooth muscle lining bronchioles contract and large amount of mucus produced.​ -Air flow severely reduced meaning FEV1 is reduced.

Question 28

what is emphysemas impact?

Answer 28

-Caused by smoking or air pollution, where particles trapped in alveoli.​ -Attracts phagocytes to area which produce an enzyme which breaks down elastin.​ -Loss of elastin reduced alveoli ability to recoil and destroys the alveoli wall so gas exchange rate decreases.