Chapter 7 Key Concepts Flashcards Preview

A Biological Processes PM June 12th 2017 > Chapter 7 Key Concepts > Flashcards

Flashcards in Chapter 7 Key Concepts Deck (26)
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1
Q

Why are the amoeba able to rely on diffusion alone?

A

Low metabolic activity . So low oxygen demands and low CO2 production

Large SA: V

2
Q

4 charateristics of a specicalised exchange surface

A

Increased SA
Thin layers
Good blood supply
Ventilation to maintain diffusion gradient

3
Q

Why the increased SA for exchanged surfaces

A

Provides area needed for exchange

To overcome limitations of SA:V eg root hair cells and villi

4
Q

Why the thin layers for exchanged surfaces

A

Short diffusion distances
Process is fast and efficient
Eg alveoli and villi

5
Q

Why the good blood supply for exchanged surfaces

A

Steeper con grad means faster diff
Ensures substances constantly being removed and delivered to ex surface maiming steep con grad eg alveoli gills and villi

6
Q

Why the ventilation for exchanged surfaces

A

For gases
Helps maintain steep con grad for increased efficiency
Eg alveoli and fish (flow of water carrying dissolved gas)

7
Q

Adaptations of the nasal cavity

A

Large SA with good blood supply that warms air to room temp

hairy lining that secreted mucus to trap dust and bacterial protecting delicate lung tissue from irritation and infection

Moist surfaces, increase the humidity of incoming air to reduce Evap from the exchange surface

8
Q

Adaptations of the trachea

A

Main airway carrying clean warm moist air from nose to chest
Strong flexible Incomplete Cartilage rings
-stop trachea collapsing
-incomplete so food can move down the oesophagus behind the trachea

Lined with ciliated epith cells with goblet cells between and below the cili epith

9
Q

Adaptations of the bronchus

A

Left and right. Each leading to the lung.
Similar structure to trachea
Same supporting rings of cartilage but smaller

10
Q

Adaptations of the bronchioles

A

No cartilage
Walls have smooth muscle
-smooth muscle contracts, the bronchioles constrict and vice versa
-some gas ex poss as they’re lined with thin layer of flattened epith

11
Q

Adaptations of the alveoli

A
Epithelial cells, collagen, elastic fibres for elastic recoil so alveoli can stretch as air drawn in and they help squeeze air out 
Large SA
Thin layers
Good blood supply
Good ventilation
12
Q

Why does an alveoli need a large SA

A

If the lungs were like balloons SA nah big buff for amount of O2 needed to diffuse into the body

13
Q

Why does an alveoli need thin layers

A

Alveoli and Capps have one epithiual cell thin

Thin diffuse distance entre blood and air

14
Q

Why does an alveoli need good blood supply

A

Brings CO2 and carries away O2, maintain a steep con grad

15
Q

Why does an alveoli need good ventilation

A

Breathing moves air in and out of the alveoli helping maintain steep diff gradients

16
Q

Role of the lung surfactant

A

The inner layer of the alveoli is convered in a solution of water salts and lung surfactant

Surfactant makes it possible for alveoli to remain inflated
O2 dissolves in water before diffusing into the blood but also can Evap into air the in the alveoli

17
Q

What happens to the tidal volume and breathing rate as you exercise

A

Tidal vol of air moved in each breath increase from like 15 to 50 percent of the vital capacity

Breathing rate increases too so incre

18
Q

how is more SA exposed for gas exchange in an insect

A

when ox demand builds up, lactic builds up in tissues so water moves out of trachioles via osmosis

19
Q

how do larger insects eg beetles locust and grasshoppers with very high energy demands supply the excess oxygen they need

A

mechanical ventilation of the tracheal system

collapsible enlarged tracheae or airs sacs that act as reservoirs

20
Q

explain the use of collapsible enlarged tracheae or airs sacs that act as reservoirs in larger insects

A

used to increase amount of air moved thorough the gas ex system
usually inflated and deflated by the ventilating movements of the abdo and thorax

21
Q

how does the mechanical ventilation of the trachael system

A

air actively pumped into the system by muscular pumping of the abdo and or thorax

pumping changes the vol of bod
as pressure of the tracheae and tracheoles changes air moved in or expelled out

22
Q

why do fish need special respiratory systems?

A

water is viscous and has less o2 in it
it would use up too much energy to move viscous water in and out of lung like things
-SA V too small
-scales doesn’t allow gas ex

23
Q

describe the process of ram ventilation

A

ram water past the gills. meaning they cant stop moving

24
Q

in what primitive species does ram ventilation happen

A

cartilaginous fish eg sharks and rays

25
Q

5 adaptations of the thin feathery gills

A
large SA for diff
rich blood supply to maintain steep grad for diff
thin layers so short diff distance
countercurrent exchange system
tips of adjacent gill filaments overlap
26
Q

what does it mean if the tips of the gill filaments overlap?

A

increased resistance to flow of water over the gills
slows down movement of water

more time for gas ex to occur