Lesson 5: Respiration

Question 1

what gases are in the mixture of air we breathe in?

Answer 1

• nitrogen (78%)
• oxygen (21%)
• argon (1%)
• carbon dioxide (0.04%)
  and trace amounts of other gases

Question 2

what is oxygen a key reactant in?

Answer 2

aerobic cellular respiration

Question 3

how do we maintain our internal body temperature?

Answer 3

energy is released as thermal energy during cellular respiration

Question 4

what is aerobic cellular respiration

Answer 4

process we use to obtain energy from food

Question 5

how much energy is released during cellular respiration as thermal energy? what is the energy left used as (and how much is used)?

Answer 5

64% of energy released during cellular respiration is released as thermal energy; the other 36% of the energy is STORED AS ATP (adenosine triphosphate)

Question 6

what is ATP used by, and what is it used for?

Answer 6

used by cells to power almost all of their processes

Question 7

how is ATP formed?

Answer 7

when energy from the breakdown of glucose is used to attach a phosphate group onto a molecule called adenosine diphosphate (ADP).

• ADP + P –> ADP PHOSPHORYLATION + ENERGY = ATP

Question 8

what is the process that forms ATP from ADP called?

Answer 8

phosphorylation

Question 9

what is ATP?

Answer 9

the molecule where energy is STORED and used for the cell

Question 9

Where is the energy stored in ATP?

Answer 9

stored in the extra phosphate bond that you see in ATP

Question 10

what happens when the phosphate bond is broken + when is this bond broken?

Answer 10

the bond is broken when energy is needed by the cells; when the extra phosphate bond is broken, we are left with ADP plus a phosphate

Question 11

what is ATP used for?

Answer 11

to power almost all of cells energy-requiring processes, such as growth, movement, and building new molecules

Question 12

how is ATP recycled?

Answer 12

ADP and phosphate are continuously recycled and recharged with energy to form ATP molecules

Question 13

what is gas exchange

Answer 13

the process by which oxygen diffuses into the body cells and carbon dioxide diffuses out of the cells

Question 14

what is gas exchange like in simple organisms? what are examples of simple organisms

Answer 14

this can occur directly through cell membranes to/from surrounding environment; simple organisms like sponges and jellyfish

• oxygen diffuses directly from the surrounding environment through the cell membrane, and into the cells. Carbon dioxide diffuses directly from the cells of the organisms through the cell membrane into the environment

Question 15

generally, how do we get oxygen required for aerobic cellular respiration

Answer 15

gas exchange! this process is where oxygen diffuses into and carbon dioxide diffuses out of our cells

Question 16

how does the process of gas exchange and ventilation differ from simple organisms and from complex organisms like humans? what do complex organisms need instead in order to complete gas exchange?

Answer 16

simple organisms like sponges and jellyfishes are able to have oxygen directly diffuse in and out of their cell membranes (with contact to their surrounding environments); however, complex organisms like humans have so many cells in their body that do not come into contact with the environment (thus they cannot depend on simple diffusion) INSTEAD, they required a specialized organ system that accomplishes this same task

Question 17

what are the structural features that the human respiratory system needs which allows it to function well?

Answer 17

• a thin permeable respiratory membrane across which diffusion can occur
• a large surface area to facilitate gas exchange
• a good supply of blood
• a breathing system for bringing oxygen rich-air into the system

Question 18

why is it important to have a thin membrane as a structural feature of our respiratory system?

Answer 18

if we don’t have this thin membrane (thin enough to accept diffusion in and out), we won’t get oxygen in our bloodstream and the co2 out

Question 19

what is the autonomic nervous system and what does it do?

Answer 19

it is our brain’s unconcious control center for the vital functions

Question 20

what is the general process of the respiratory system when we breathe air in and out?

Answer 20

1. the diaphragm flattens and the muscles between the ribs contract, which creates more space for the lungs to expand
2. air then goes into the nose and mouth, through the trachea, and into the bronchi that split at the trachea’s base.
3. the air we breathe in goes through the bronchioles and into the alveolus, which causes the lungs to inflate
4. the vital exchange of gas occurs in the alveoli: the capillaries are packed with carbon dioxide, and the air sacks are full of oxygen.
5. due to basic diffusion, the oxygen crosses over to the capillaries (hemoglobin grabs it up), while the carbon dioxide is unloaded into the lungs.
6. the oxygen-rich hemoglobin is then transported throughout the body by the bloodstream
7. now, our lungs have lots of carbon dioxide: we get rid of the co2 by exhaling it- the diaphragm balls up, and the intercostal muscles relax, which makes the chest cavities smaller and forces the lungs to compress
8. the co2 rich air is then expelled out of the body, and the process repeats again

Question 21

breakdown: what is the process of inhalation?

Answer 21

• air enters through the nose and the mouth
• the air is then warmed and moistened in the nasal passage before it enters the lungs

Question 22

what is the nasal passage lined with in order to prevent airborne particles from coming in?

Answer 22

the nasal passage is lined with hairs and mucus to filter out and trap any airbone particles (dust, bacteria, viruses, etc)

Question 23

breakdown: what is the process of inhalation in the upper tract?

Answer 23

• air travels into the pharynx (throat); it then reaches the glottis (opening to trachea)
• the trachea has c-shaped rings of cartilage around it to keep it rigid and open (prevents the trachea from being crushed or closed as we need air to get through it)

Question 24

what features of the trachea helps protect the lungs?

Answer 24

the trachea is lined with mucus producing cells and cilia (hair like projections) which protect the lungs from foreign matter by trapping the particles and sweeping them upward to be swallowed, coughed, or sneezed out

Question 25

what does the mucus that coats the lungs help with?

Answer 25

• serves to slow harmful particles down due to its thick flow: the mucus flow is caused by pumping cilia that act like ores; the cilia are slender projections that stick up from the cell surfaces
• acts as a filter that renews itself: it traps particles and bacteria

Question 26

breakdown: how does oxygen travel into the lungs? (bronchi, alveoli..)

Answer 26

• the trachea branches into two bronchi; the bronchi then branch off into smaller tubes called bronchioles: these tubes end in small sacs called the alveoli which are surrounded by a network of capillaries
• each alveolus is tiny, and is surrounded by a bed of even tinier capillaries

Question 27

what is the major organ of the respiratory system? what help does this organ provide to the respiratory process? where is it located?

Answer 27

your two lungs
- these organs provide the thin respiratory membrane, large surface area, and supply of blood required (key structural features of respiratory system)
- the lungs are contained within your thoracic cavity (chest cavity) and are protected by the rib cage due to the fact that its hard and sturdy

Question 28

what does a large number of alveoli allow for? what does it help with?

Answer 28

a large number of alveoli allows for a maximum surface area for gas exchange; as a result, it allows for easy diffusion of gases across the membrane and into the blood

Question 29

what does the thin membrane that alveoli have help with?

Answer 29

the thin membrane they have is a key characteristic of the alveoli- alveoli is where oxygen is going to end up
- it needs to diffuse out of the alveoli and into the blood now, by using the capillaries surrounding the alveoli
- they are made of extremely thin membranes which allow for very EASY DIFFUSION of GASES into the BLOOD

Question 30

how is oxygen and co2 diffused in the alveoli?

Answer 30

once oxygen is diffused into the blood, it diffuses out of the blood into INTERSTITIAL FLUID (fluid that surrounds the cells of all tissues); then, it will move from the fluid into the cells

as for co2, it is transported out of the body through exhalation from the lungs

Question 31

difference between gas exchange and ventilation

Answer 31

• gas exchange is the process of gases diffusing in and out of tissues with their concentration gradient
• ventilation is the process of moving oxygen-rich air to the lungs and carbon dioxide-rich air away from the lungs

Question 32

what is the diaphragm and what does it do to help ventilation? what do these processes act to do/help with?

Answer 32

diaphragm: sheet of muscle that seperates the thoracic (chest) cavity from the abdominal cavity
- when you inhale, the muscle contracts which shortens and flattens the diaphragm; at the same time, the external intercostal muscle between each rib contracts, which pulls the rib cage up and out
- all of these processes act to INCREASE the VOLUME of the thoracic (chest) cavity, which DECREASES the PRESSURE and causes air to rush into the lungs

Question 33

describe the amount of pressure and space for each scenario: diaphragm contracts and intercostal muscles contract- ____ ; diaphragm relaxes and intercostal muscles relax- ____

Answer 33

• Diaphragm contracts & Intercostal muscles contract = More space, less pressure (brings air in)
• Diaphragm relaxes & Intercostal muscles relax = Less space, more pressure (push air out)
• When there is more volume of the chest cavity, the lungs can expand to fill the space (and vice versa)

Question 34

what happens with the diaphragm when you exhale?

Answer 34

• the diaphragm relaxes which lengthens and raises the muscle; at the same time, your external intercostal muscle between each rib relaxes which pulls the rib cage in and down
• all of these processes act to DECREASE the VOLUME and INCREASE the PRESSURE of the thoracic (chest) cavity, thus pushing the air out of the lungs

Question 35

what ensures that the lungs avoid problems due to friction on the delicate tissues?

Answer 35

pleural membranes: these are membranes that cover the lungs and line the thoracic (chest) cavity
- it is filled with fluid that acts like a lubricant to avoid this possible friction against the lungs