Gaseous Exchange

Question 1

gaseous exchange?
breathing?
respiratory surface?

Question 2

exchange of gases in plants takes place through?
during day & night time, plants take in & give out?
what are cuticles?

Answer 2

stomata, intercellular space, cuticle & lenticels.
CO2 O2
O2 CO2
external covering of leaves & young stems

Question 3

what is the main source of gaseous exchange in plants?
what are lenticles?

Answer 3

stomata
In woody stems & roots, there are dead cells beneath the epidermis. These dead cells constitude cork tissues. These cork tissues have pores

Question 4

briefly relate photosynthesis with respiration in plants ?

Answer 4

pg 6

Question 5

what are the organs responsible for gaseous exchange?
what does the air passageway consist of?
why breathing in fresh air is to get more energy?

Answer 5

lungs and air passages which lead to the lungs.
nose, pharynx, larynx, trachea, bronchi & bronchioles. Alveoli
O2 is needed for respiration is needed for energy

Question 6

nose is divided into?
nostrils? they lead to?
where are neurons located? function?
where is cilia?
how are mucus produced? function?

Answer 6

• 2 parts
• external opening of the nose having hairs. nasal cavity
• top of nasal cavity has lining of nerve cells, sense of smell.
• walls & base of nasal cavity are lined w/ cilia
• b/w ciliated epithelial cells are goblet cells which produce mucus, sticky fluid.
• trap large dust particles, moistens air

Question 7

function of nasal cavity?
the _______ sweeps mucus towards _________, which is then either ____ or ______-

Answer 7

cilia, pharynx, swallowed or spit out

Question 8

from nasal cavity, where does the air go? then?
the cavity of larynx? epiglottis is?
trachea?

Answer 8

• towards a channel called pharynx at the back of the mouth. then into larynx/ voice box is a cartilaginous strucutre. it surrounds the upper end of trachea
• glottis
• cartilaginous strucutre
• tube running from larynx to lungs

Question 9

how is trachea held open? when is it closed?

Answer 9

it is held permanently open by C shaped rings of cartilage in its walls. the cartilage rings also keep the trachea open when it develops low internal air pressure due to _________________.

inhalation

Question 10

trachea divides into?
how are alveolar ducts formed?

Answer 10

• 2 branches leading to each lungs (bronchi)
• each bronchus divides again & again to form a mass of very fine branches called bronchioles.
• the bronchioles branch into many short tubes of equal diameter called alveolar ducts which end in tiny hollow air sacs.
  bronchi have irregularly shaped plates of cartilage.

Question 11

what is alveoli?
the bronchioles branch into many short tubes of ______________ called _______________.

Answer 11

tiny bubble-like pockets which are the respiratory surface of a mammal.
equal diameter
alveolar ducts

Question 12

identify throat?
what is pleura?
what is the function of fluid in pleura?

Answer 12

pharynx
each lung is surrounded by a double membrane.
the space between the double membrane is filled by a film of fluid. the fluid enables them to silde against each other during respiration.

Question 13

why are lungs spongy?
how does gas exchange in alveoli occur? explain? name the membranes?
each alveolus is surrounded by?
lungs are protected by?

Answer 13

• due to presence of alveoli
• via diffusion
• the inner surface of the alveoli has moisture. O2 dissolves in this moisture and then diffuses across the thin-walled blood capillaries into the blood.
  CO2 diffuses across the membrane of alveolus and go into the air present within the alveolus.
• network of capillaries
• ribs and intercostal muscles.

Question 14

during inhalation, what elevates the ribs?
what increases the volume of chest cavity?
what causes air to move into the lungs?

Answer 14

• external intercostal mucles contract.
• muscles of diaphragm contract increasing the chest cavity & lowering the diaphragm.
• the increased size of the chest cavity causes the pressure in cavity to drop below atmospheric pressure & air goes into equalizing the pressure.

Question 15

exhalation?

Question 16

normal breathing rate?
how exercise effect rate of breathing?

Question 17

bronchitis? treatment?

Answer 17

inflammation of the lining of the air passages like trachea, bronchi & bronchioles
don’t smoke
drink plenty of water
take rest
an inhaler may be taken

Question 18

Casues of bronchitis?

Answer 18

Acute bronchitis: side effect of viral infection like flu may last for few days.
Chronic bronchitis: commonly caused by tobacco smoking & to a lesser extent air pollution.

Question 19

allergic response is the main cause of?
secretion of excess mucus is the main symptom of?
difficult to walk is the symptom of?
inflammation of alveoli?
smoking leads to?

Answer 19

asthma
bronchitis
emphysema
pneumonia
emphysema, bronchitis & lung cancer

Question 20

symptoms of emphysema?

Answer 20

increasing breathlessnes
in advance case, the patient finds it difficult to walk
the lungs loose elasticity
inflammation & narrowing of bronchioles also occur

Question 21

What is emphysema and treatment?

Answer 21

over-inflation of alveoli in lungs, causing a decrease in lung function
avoid smoking
treatment methods dont cure or reverse damge to the lungs

Question 22

Causes and symptoms of asthma?

Answer 22

• an allergic response to substances like
• more difficulty breathing out than breathing in
  whistling sound is caused by breathing
  in body, secretion of excess mucus & swelling of the lining of the air passages.

faces phe

Question 23

Cause of emphysema

Answer 23

long term irritation of the lungs, most commonly by ciagrette smoke, air pollution & industrial dust.

Question 24

Symptoms of bronchitis?

Answer 24

• In body, one of the symtoms is secretion of excess mucus from the goblet cells in response to irritation.
• The main symptom is cough which occus repeatedly.
  coughing & breathlessnes increases as the disease progresses.

Question 25

symptoms and causes of pneumonia?

Answer 25

Fever, shaking chills, diarrhoea, nausea, cough, chest pain, headache, sore throat
common cause is bacteria strep-to-coccus pneumonia-e

she chewed strawberry cake n finished double. 8

Question 26

treatment for asthma?

Answer 26

mild attack: bronchodilators that dilate the airway
inhaler help them breathe
long term disease & has no cure
treated with 2 types of medicines: long term control & quick relief

Question 27

when does lung cancer usually start?
treatment of lung cancer?
main cause of cancer?

Answer 27

at the epithelium of the bronchioles.
pneumonectomy
tobacco smoke

Question 28

symptoms of lung cancer?

Answer 28

Coughing that gets worse or doesn’t go away.
Chest pain.
Shortness of breath.

Question 29

what toxic compound cigarette contain?
what is the force that drives air into the lungs?
define breathing? how is expansion and contraction of lungs done?

Answer 29

1. nicotine
2. tar (brown sticky substance)
3. carcinogen (cancer causing chemicals)
4. carbon monoxide
5. irritants (chemical that irritate)

air pressure

Question 30

effects of cigarette on the circulatory system? and lungs?

Question 31

difference between breathing & respiration? & photosynthesis and respiration

Question 32

Amount of oxygen
Amount of carbon dioxide
Amount of nitrogen
Amount of water vapours Variable Saturated
Amount of dust particles Variable Almost none
Temperature

Answer 32

Amount of oxygen 21% 16%
Amount of carbon dioxide 0.04% 4%
Amount of nitrogen 79% 79%
Amount of water vapours Variable Saturated
Amount of dust particles Variable Almost none
Temperature Variable Almost equal to body temperature