Life Processes in Organisms Flashcards
(41 cards)
Respiration
The breakdown o glucose in presence of O2 to produce energy in thr form of ATP. Waste produts fromed are H2O and CO2.
Ventilation
The physical process that gets O2 to the gas exchange surface and CO2 out of the body.
Gas Exchange
The swapping of O2 and CO2 across the cell membrane of a gas exchange surface.
Adaptation mammal 1
Tidal Ventilation
Breathing is tidal, with air entering and leaving the lung by the same route. Lungs are a passive, elastic structure which allow the ling to move, synchronised with surrounding muscular functions.
* A lung is never emptied completely- some air always remains. Each inspiration merely tops up the air already in the lungs.
* This assists in minimising the amount of water lost in each expired breath.
Adaptation mammal 2
Internal Lungs
In mammals, lungs are found internally (inside the body) and have a high humidity, which reduces the amount of water lost from the surfaces by evaporation.
Adaptation mammal 3
Mucus and Cilia in Trachea
In mammals, cilia are tiny hair-like structures found in the
respiratory tract, including the trachea and bronchi (not found
in the alveoli). They create wave-like movement to sweep
mucus upwards to be swallowed or expelled at the
mouth/nose (along with trapped debris)
Living in a terrestrial environment poses other problems. The
dirt and dust particles could seriously damage the delicate GE
surface. The lining of the air passages is covered with many
cilia. Mucus is secreted by cells and traps dust particles, which
are removed by the cilia and air movements. This allows the gas
exchange surfaces to be kept clear.
Cilia and Mucus also traps
bacteria which is removed
preventing infection at the gas
exchange surface.
Adaptation mammal 4
Surfactant
Surfactant is a mixture of phospholipids and
proteins by alveolar cells
* Surfactant decreases surface cohesion
* This prevents the alveoli from collapsing when we exhale (breathe out).
* No surfactant also means that the lung cannot inflate normally
Advantage/Disadvantage Factors of animal environments
Advantage
* Animals have higher O2 in their atmosphere (approximately 21%)
* Air is less dense than water (low energy needed to extract O2)
* Diffusion is faster in air
Disadvantage
* Exposed parts of organism risk drying out
* Dust/Bacteria can cause infection and damage gas exchange surfaces
* Terrestrial air temp is varied
Factors of fish environments
Advantages
- Temperature does not vary
- No risk of dessication
- Low dust and Bacteria
Disadvantages
- <1% O2 in the water
- Water is very dense - lots of energy required to extract O2
- Diffusion is slower
Why animals cant live in fish enviros and why fish cant live in animal enviros
Because they dont have the adaptations to function in that environment. This means they cannot sustain life processes.
How dust/bacteria/damage to gas exchange surfaces is bad
- shrinks SA of gas exchange membrane causing slower/less efficient diffusion
- can cause a loss of surfactant
Taxonomic group of Humans/mammals:
Phylum: chordata
Class: mammalia
- Live young
- warm blooded
- produce milk
- hair or fur
Ecological Habitat/niche of human/mammals
Usually Terrestrial (i.e. live on land)
• Not restricted to moist
environments as internal lungs
keep moist.
Structures of the Mammal Gas Exchange System
Nasal Cavity - Trachea - Bronchi - Bronchioles - Alveoli
These structures are involved in the delivery of O2 to the gas
exchange surface (alveoli) and removal of CO2
from capillaries and
out of the body (through ventilation).
Adaptation mammal #5
C-shaped bands of cartilage
Cartilage is a strong, flexible connective tissue that supports
and protects various structures in the body.
C-shaped bands of cartilage support the trachea and keep it
open when breathing out. This keeps the airways clear.
Always link to
How X links to the survival of the organism in that environment
(Ie moisture for survival on land)
Advantages and disadvantages of air with links
As a gas exchange medium, air has many advantages over water:
• Air has a much higher oxygen concentration than water
• Diffusion occurs more quickly so less ventilation of the surface is
needed
• Less energy is needed to move air through the respiratory system
than water
BUT
as the gas exchange surface must be moist, in terrestrial animals water
is continuously lost from the gas exchange surface by evaporation
SO
the gas exchange surface is found internally to reduce water loss.
Air system step by step
Once O2 is inhaled by the nose or mouth it reaches the trachea:
Hollow tube
held open by
‘C’ shaped
bands of
cartilage.
• It branches into
the two bronchi
(one: bronchus)
which also have
cartilaginous
rings.
Bronchus then branch into smaller
tubes called bronchioles which
lead into grape-like clusters of
thin-walled air sacs called alveoli
(one: alveolus) which are
surrounded by blood capillaries.
Oxygen diffuses across
the moist lining of the
alveoli into the
capillaries.
• CO2 diffuses out of the
capillary and into the air
in the alveoli.
(O2 out of alveoli and O2 in by the capillaries.)
Taxonomic groups of fish
Phylum: Chordata
Class: Pisces
- Cold Blooded
- Gills
- Fins
Ecological niche of fish
- Aquatic - Low O2, dense medium
- High energy requirement, fast moving through dense area
- Slower Diffusion
- medium sized, need circulatory system
Structure of fish Gas Exchange system
Mouth -Gill Rakers -Gill Arches -Primary lamellae -Secondary lamellae -Operculum
Fish Gas Exchange using gills (not that Important)
Fish have a highly efficient system. They tend to have a high demand
for oxygen. Bony fish are able to extract nearly 80% of the dissolved
oxygen from the water, This is crucial as water contains much less
oxygen than air, The gas exchange system is very efficient with the help of counter-current flow of
blood and water over gill lamella.
The gas exchange organ in fish is the gills. Gills are filamentous out-foldings of the body which increase the surface area for gas exchange.
Adaptations of the GE system in Fish
Primary and Secondary Lamellae
2. Support
3. Continuous ventilation
4. Counter current flow
5. Keeping the GE surfaces clear
Adaptation: Primary and
Secondary Lamellae
fish
Gills are split up into primary lamellae that look like a V in cross section
Primary lamellae have a very large surface area that is further increased by many, even thinner secondary lamellae.
Each secondary lamella is a fold in the primary lamellae and contains many blood capillaries.
As water moves over the lamellae, oxygen dissolved in it diffuses into the capillaries.
Gills have a very large surface area:
four arches with primary lamellae that are very thin and flat with secondary lamellae folds
* Gills are thin-walled and in close contact with
water: short distance for diffusion
* Gills have a very high blood supply to bring CO2 and carry away O2 ➔ dark red colour
* Gills are moist: fish live in water!
