1.2 Cardiovascular and respiratory systems 3

Question 1

What does the respiratory system consist of

Answer 1

-nose
-series of airways
-lungs
-respiratory muscles

Question 2

Name the 2 functions of the respiratory system

Answer 2

-pulmonary ventilation- inspiration & expiration of air

-gaseous exchange- (external and internal)

Question 3

What occurs in gaseous exchange

Answer 3

external respiration- movement of oxygen into the blood and CO2 into lungs

internal respiration- release of oxygen to respiring cells for energy production and collection of waste products

Question 4

What are alveoli

Answer 4

clusters of air sacs covered in network of capillaries

-site for gaseous exchange

Question 5

What is gaseous exchange

Answer 5

movement of oxygen from alveoli into blood stream and CO2 from bloodstream into alveoli

Question 6

What is external respiration

Answer 6

movement of oxygen into blood stream and carbon dioxide into lungs

Question 7

What is internal respiration

Answer 7

release of O2 to respiring cells for energy production

& collection of waste products

Question 8

Name the 4 steps of the pathway of air through respiratory organs

Answer 8

1. air into nasal cavity through nose
2. travels down pharynx, larynx, trachea
3. trachea divides into right, left bronchi as they enter lung

4.bronchi divide into brochioles- end in alveoliar ducts

Question 9

What occurs during inspiration (breathing in)

Answer 9

diaphragm contracts, moves downwards

intercostal muscles contract moving ribs upwards, outwards - increases size of chest- decreases air pressure inside it- sucks air into the lungs.

Question 10

What occurs during expiration (breathing out)

Answer 10

diaphragm relaxes- returns to domed shape

intercostal muscles relax so the ribs move inwards, downwards- decreases size of chest- increases air pressure in chest- air is forced out lungs

Question 11

Where does gaseous exchange occur and by what process

Answer 11

occurs in lungs
takes place by diffusion

Question 12

What occurs in gaseous exchange

Answer 12

high concentration of oxygen in the alveoli and a low concentration of oxygen in the blood, so oxygen diffuses from the alveoli into the blood

high concentration of carbon dioxide in the blood and a low concentration in the alveoli, so carbon dioxide diffuses from the blood into the alveoli.

Question 13

Name 2 ways oxygen can be transported

Answer 13

-blood plasma

-haemoglobin in red blood cells

Question 14

What is oxygen

Answer 14

essential gas required for aerobic energy production in kmuscle cells

Question 15

What is carbon dioxide

Answer 15

waste product of aerobic energy prdocyution in muscle cells

Question 16

Name the 3 ways carbon dioxide can be transported

Answer 16

-carried as carbonic acid

-carried within haemoglobin

-disollved in plasma

Question 17

What is tidal volume

Answer 17

volume of air inspired/ expired per breath

Question 18

What is the formula for minute ventilation

Answer 18

tidal volume x breathing rate = minute ventilation

Question 19

Explain the role of the respiratory system when responding to exercise snd recovery

Answer 19

-when we start to exercise- demand for oxygen by muscles increases

-respiratory systems role is to increase supply of air to alveoli and therefore oxygen for gaseous exchange

Question 20

Explain what occurs to breathing rate in response to exercise

Answer 20

br increases until we reach our max (50-60 breathes per min)

sub-maximal- br can plateau- supply of oxygen meeting demand from muscles

Question 21

Explain what occurs to tidal volume in response to exercise

Answer 21

tidal volume increases

Question 22

Explain what occurs to minute ventilation in response to exercise

Question 23

Describe what occurs in the mechanics of inspiration at rest

Answer 23

-active process

-external intercostal muscles between ribs CONTRACT -> pulls chest walls up & out

-diaphragm- CONTRACTS, FLATTENS -> increasing size of chest

Question 24

Name the additional inspiratory muscles recruited for inspiration during exercise

Answer 24

-sternocleidomastoid
-pectoralis minor

Question 25

How do the sternocleidomastoid and pectoralis minor increase breathing depth and volume during exercise

Answer 25

create greater up and outward movement of rib cage and sternum

greater movement ^ volume and decreases pressure inside thoracic cavity more than at rest

increases breathing depth and volume of air inspired#

Question 26

What occurs during expiration at rest

Answer 26

external intercostals relax- lowers rib cage, sternum- down and in

diaphragm relaxes, returns to its dome shape

—> decreases vol of thoracic cavity- increases pressure above atmosphere outside body- air is pushed out of lungs

Question 27

Name the process of expiration at rest

Answer 27

passive process

Question 28

Name the process of expiration during exercise

Answer 28

active

Question 29

Name the additional expiratory muscles recruted to give larger force of contraction in expiration during exercise

Answer 29

internal intercostals
rectus abdominis

—> creates greater down, inward movement of rib cage and sternum- decreases vol, increases pressure insude thoracic cavity- increases br and vol of air expired

Question 30

What is the respiratory control centre (RCC)

Answer 30

control centre in medulla oblongata responsible for respiratory regulation

Question 31

What is minute ventiliation

Answer 31

volume of air inspired/ expired per minute

Question 32

What is respiratory control

Answer 32

when exercise/ recovery occurs- brain gets involved to regulate br

Question 33

Name the 2 centres within the respiratory control centre (RCC)

Answer 33

inspiratory centre (IC)- stimulates inspiratory muscles to contract at rest and during exercise- INSPIRATION

expiratory centre (EC)- inactive at rest- stimulates additional expiratory muscles to contract during exercise- EXPIRATION

Question 34

What occurs in terms of regulatory regulation at rest

Answer 34

inspiratory centre is responsible for rhymic cycle of breathing

-nerve impulses are generated and stimulate inspiratory muscles causing them to contract via:

-intercostal nerve to external intercostals
-phrenic nerve to diaphragm

causes thoracic cavity vol to be increase lowering lung air pressure

expiratory centre = inactive

Question 35

What occurs in terms of regulatory regulation during exercise

Answer 35

breathing rate & depth increases to meet demand for oxygen

sensory nerves relay info to RCC where response initiated by IC and EC

chemoreceptors in aorta and carotid arteries pick up increase in blood acidity, increase in CO2 conc and decrease O2 conc

Question 36

Name the 3 different neural controls

Answer 36

thermoreceptors- inform of increase in blood temp

proprioceptors- inform of motor activity in muscles and joints

barorecptors- located in lung tissues, bronchioles

Question 37

Explain what occurs in the inspiratory centre which has been informed on what to do by the RCC during respiratory regulation during exercise

Answer 37

chemo, thermo, propriorecpetors inform IC
–> increases stimulation of phrenic nerve so diaphragm contracts with more force

-IC also increases stimulation of intercostal nerve so external intercostals contract with more force

-stimulates additional muscles to contract – sternocleidomastoid & pectoralis minor

increases volume of thoracic cavity and decreases pressure in lungs more than at rest.

more air rushes in - increasing depth of breathing.

Question 38

Explain what occurs in the experiatory centre which has been informed on what to do by the RCC during respiratory regulation during exercise

Answer 38

barorecptors inform expiratory centre on extent of lung inflation

stimulates additional muscles to contract – internal intercostals & rectus abdominis

this decreases volume of thoracic cavity and increases pressure in lungs more than at rest.

more air rushes out - increasing rate of breathing.

Question 39

Meaning of partial pressure

Answer 39

pressure exerted by individual gas held in mixture of gases