Gas Exchabge

Question 1

How does your body adapt from aerobic excercise

Answer 1

None makes more red blood cells so more oxygen can be transported in the blood,
your arteries become wider and more elastic so that your blood pressure falls
Your heart grows bigger (hypertrophies) and the walls become thicker so that they can pump more blood with each beat. This means it doesn’t have to beat so fast.
More blood capillaries grow within your muscles so that more oxygen can get there more quickly
Your heart rate returns to normal more quickly following excercise
More blood capillaries also grow around the alveoli in your lungs so more oxygen is taken into the blood and more carbon dioxide is released .
Your diaphragm and intercostal muscles become stronger so they can make your chest cavity bigger meaning you can breathe in more air

Question 2

How does excercise cause adaptations within your muscles bones , joints and energy systems

Answer 2

Your muscles grow lager and stronger
Your tendons grow bigger and stronger
Your body gets better at respiring fat , even when you aren’t excercise for
Your muscles get better at using oxygen
Your oxygen consumption rate increases
Ligaments and cartilage at your joints grow thicker and stronger
Bones become stronger

Question 3

What happens when we breath in

Answer 3

Chest expands and the diaphragm contracts , increasing volume in the thorax and atmospheric pressure pushes air into the lungs

Question 4

How is the thorax adapted

Answer 4

Two pleural membranes are internally lubricated and cause the chest movement to be frictionless

Question 5

How does exhalation occur

Answer 5

External intercostal sand diaphragm relax and the chest contracts and the elastic recoil causes the pressure in the thorax to increase and forces air out of the lungs

Question 6

How do we increase the rate of exhalation

Answer 6

During active breathing , as when we run , the internal intercostal muscles need to contract in order to increase the rate of exhalation which would otherwise be too low during vigorous exercise

Question 7

How does gaseous exchange occur

Answer 7

Gas exchange will only occur so long as there is a concentration gradient of the gases in the appropriate directions .the heart continually replaced blood in contact with the alveoli with fresh deoxygenated blood , keeping the oxygen concentration low and the carbon dioxide concentration high on the capillary side of the respiratory membrane . The process of ventilation maintains the oxygen concentration high and the carbon dioxide concentration low on the alveolar side of the respiratory membrane .it the concentration of both gases were the Same no gas exchange would occur

Question 8

What is asthma

Answer 8

A chronic inflammatory problem that causes the overproduction of mucas and reduction in diameters of smaller bronchi and bronichles in response to an allergen

Question 9

What is bronchitis

Answer 9

An inflammatory response involving hyoertrophy of glands and goblet cells lining the bronchi. Atmospheric pollution may be a contributory factor , excessive mucus being produced as sputum. Chemicals in tar paralyse cilia and stimulate additional mucus production , mucus gravitates to the lungs , bacteria becomes trapped in the mucus and causes infection and irritation . Mucus blocks the airways and breathing is more difficult and gas exchange is reduced

Question 10

How can cigarette smoking harm your lungs

Answer 10

It produces lots of inflammatory substances and is the major cause of chronic bronchitis , lasting from months to years . Nicotine in the smoke dissolves in the alveolar capillaries and then causes adrenaline to be secretes , raising cardiac output and blood pressure . Cigarette smoking also deactivates the enzyme anti trypsin which normally inhibits the proteases and elastases which would otherwise attack the alveoli

Question 11

What is emphysema

Answer 11

Removal of soot by white cells and continuous coughing damages the alveoli. Alveolar walls disintegrate resulting in large air spaces which do not close during exhalation . Reduced surface area for gaseous exchange and loss of elasticity make exhalation very hard are effects. The major cause of this problem is long term irritation of the air passages as from cigarette smoking or air pollution

Question 12

What is diffusion

Answer 12

Diffusion is the net passive movement of particles (atoms, ions or molecules) from a region in which they are in higher concentration to regions of lower concentration.

Question 13

What is aerobic excercise

Answer 13

Submaximal excercise which gets your heart rate and breathing rate up over a sustained period , for example : jogging , swimming , cycling . If you perform aerobic excercise regularly your body adapts. It is excellent for the health of your heart and lung

Question 14

How does diffusion occur in humans

Answer 14

In humans gases drawn into the lungs diffuse across the thin walls of the alveoli and the blood

Question 15

What happens when we breathe

Answer 15

Air is moved into and out of our lungs , this involves different parts of the respiratory system inside the thorax.
When we breathe in , air enters through the nose and mouths in the nose the air is moistened and warmed .
The air travels down the trachea to the lungs , tiny hairs called cilia help to remove dirt and microorganisms.
The air enters the lungs through the bronchi which branch and divide to form bronichles.
At the end of the bronichles are air sacks . Alveoli are in the air sacs , the alveoli are covered in tiny blood capillaries where oxygen and carbon dioxide are exchanged

Question 16

What surrounds the lungs

Answer 16

Pleural membranes . An inner one attached to the lung surface and an outer one attached to the thoracic wall and diaphragm. Between the membranes is a little fluid that helps them slide smoothly over each other.

Question 17

What is outside the pleural membranes

Answer 17

The ribs , joined together by intercostal muscles, there are two sets of intercostal muscles : external and internal

Question 18

What is below the lungs

Answer 18

The diaphragm , a large sheet of tough tendon tissue surrounded by muscle tissue that attaches to the thorax .

Question 19

What do the pleural membranes , ribs , intercostal muscles and diaphragm do

Answer 19

Work together to allow breathing

Question 20

What is ventilation

Answer 20

The way that oxygen is taken into our bodies and carbon dioxide removed

Question 21

How are the changes in thorax volume caused

Answer 21

The diaphragm and intercostal muscles . In gentle breathing , only the diaphragm . I’n deep breathing such as during exercise the intercostal muscles and ribs become involved also

Question 22

What happens during inhalation

Answer 22

1.the diaphragm contracts and flattens in shape
2.The external intercostal muscles contract making the ribs move upwards and outwards
3.these changes cause the volume of the thorax to increase
4.this causes air pressures to decrease 5. This decrease in pressure draws air into the lungs
Rings of cartilage in the trachea and bronchi keep air passages open and preven them from collapsing when air pressure decreases and bursting when pressure increased

Question 23

What happens during exhalation

Answer 23

1. The diaphragm relaxes and returns to its domed shape, pushed up by the liver and stomach. This means it pushes up on the lungs.
2. The external intercostal muscles relax, allowing the Ribs to drop back down. This also presses on the lungs. If you are breathing hard internal intercostal muscles also contract, helping the Ribs to move down
3. These changes cause the volume of the thorax to decrease , causing air pressure in the thorax to increase and air is then pushed out of the lungs

Question 24

What happens to other gases in the air we breathe in

Answer 24

Oxygen is diffused into the blood and all other gases are breathed out almost unchanged

Question 25

Why does air enter the body

Answer 25

Because the air pressure inside the lungs is lower than air pressure outside the body. Air leaves the boy because air pressure inside is higher than outside

Question 26

How are alveoli adapted

Answer 26

. Thin permeable walls which keeps the distance over which diffusion of gases takes place between the air air and blood to a minimum
.moist lining , in which the gases dissolve before they diffuse across the cell membranes
.a large surface area for diffusion
. Rich blood supply for High concentration gradients for the gases , because the blood is continually flowing past the air sacs , delivering excess carbon dioxide and taking on additional oxygen and because of ventilation of the lungs which refreshes the air in the air sacs
Large surface area to volume ratio more gases can diffuse at any time

Question 27

What does carcinogens mean

Answer 27

Something that caused cancer

Question 28

What are harmful substances found in cigarettes

Answer 28

Nicotine , carbon monoxide and tar

Question 29

Why are pregnant women advised not to smoke

Answer 29

It reduces the amount of oxygen reaching the fetus and results in underdevelopment

Question 30

How does blood reach the lungs

Answer 30

Blood arrives at the lungs in the pulmonary artery , the blood is deoxygenate. Oxygen has been used up by the body cells during reputation , the blood also contains Los of co2. Each pulmonary artery branches many times to form capillaries. These are in direct contact with the tiny alveoli of the lungs , it is here that gas exchange takes place. Co2 diffuses out of the blood and oxygen diffuses into the blood . Oxygenated blood then leaves the kind in the pulmonary vein

Question 31

How does smoking cause cancer

Answer 31

Carcinogenic chemicals in tar cause mutation in the Dan of lung cells , the cells multiply out of control and form a tumour that blocks the airways or colonises other tissues

Question 32

What happens to the alveoli when you inhale and exhale

Answer 32

When you inhale they inflate and when you exhale they deflate , when they loose elasticity it is difficult for them to do this

Question 33

How does carbon monoxide harm you

Answer 33

Has a greater affinity for haemoglobin than oxygen and reduces the oxygen carrying capacity of the blood

Question 34

Why is nicotine harmful

Answer 34

It’s is an addictive simulant and increased blood pressure by increasing adrenaline release narrowing vessel walls . Increases heart rate because it stimulates adrenaline release and increased damage to vessel walls , coronary heart disease and stroke

Question 35

Why should u breathe through ur nose

Answer 35

1) Air inhaled through the nose is warmed and moistened, so it does not irritate the sensitive airways
7) Breathing through the nose helps regulate the volume of air breathed as the nasal passages are less wide so that it can effectively match the body’s oxygen needs.