Module 3 Flashcards
(77 cards)
1
Q
Why do single celled organisms not need transport systems? (3)
A
- High SA:V ratio (1)
- Short diffusion pathway (1)
- Absorb gases through diffusion (1)
2
Q
Adaptations of lungs (6)
A
- Hundreds of millions of alveoli give large
surface area (2) - Lots of capillaries give good blood supply (2)
- Walls of the alveoli and capillaries are only one
cell thick, giving a short diffusion distance (2)
3
Q
Function of goblet cells (1)
A
- Secretes mucus to trap dust and
microorganisms (1)
4
Q
Function of Cilia (1)
A
- Beats to move mucus up to be swallowed and
destroyed by stomach acid (1)
5
Q
Function of smooth muscle (1)
A
- Controls the expansion and narrowing of
airways (1)
6
Q
Function and structure of cartilage (3)
A
- Found in walls as rings (1)
- Strength and flexibility to provide support (1)
- Prevents airways from collapsing when
pressure drops during inhalation (1)
7
Q
What are the steps of inhalation (4)
A
- Diaphragm contracts and flattens (1)
- Intercostal muscles contract to move the
ribcage up and out (1) - Increase in thorax volume causes pressure
drop (1) - Pressure gradient sucks air into lungs (1)
8
Q
What are the steps of exhalation (4)
A
- Diaphragm relaxes and forms a dome shape
(1) - Intercostal muscles relax to move ribcage down
and in (1) - Decrease in thorax volume causes pressure
increase (1) - Pressure gradient pushes air out of the lungs (1)
9
Q
What is a spirometer used for? (1)
A
- To investigate the volume air that an individual
is capable of breathing in and out (1)
10
Q
What is meant by tidal volume? (1)
A
- The volume of air in each breath (1)
11
Q
What is meant by vital capacity? (1)
A
- The maximum volume of air a person can expel
from the lungs after a maximum inhalation (1)
12
Q
What’s meant by breathing rate? (1)
A
- The number of breaths taken per second (1)
13
Q
Why do spirometers contain the chemical soda lime? (2)
A
- It will absorb any carbon dioxide (1)
- Which will be toxic if accumulated (1)
14
Q
Structure of gills (4)
A
- Each gill is made up of many gill filaments
stacked on top of each other (1) - Filaments are covered in lamellae (1)
- Which are filled with capillaries (1)
- Each gill covered in protective bony flap, the
operculum (1)
15
Q
Why are fish said to have a counter-current system? (2)
A
- Blood in capillaries flow in opposite directions
(1) - Maintains the concentration gradient of oxygen
in the blood (1)
16
Q
How are fish gills ventilated? (5)
A
- When the fish opens its mouth, the buccal
cavity lowers, increasing mouth volume (1) - Pressure in the mouth drops, causing the water
to move into the buccal cavity (1) - When the fish closes its mouth, the buccal
cavity moves up, reducing its volume (1) - Pressure increases, forcing water across the gill
filaments (1) - As it moves across, it increases pressure and
forces operculum open on each side, allowing
water to leave the gills (1)
17
Q
How does insects tracheal insect work? (3)
A
- Air enters through spiracles (1)
- Air moves into trachea and branches into many
tracheoles that are thin and porous (1) - Rhythmic abdominal movements control push
air out and into spiracles and maintain steep
concentration gradient (1)
18
Q
What do plants need transport systems? (3)
A
- Attain water for keeping cells turgid (1)
- Sugars for respiration (1)
- Remove waste substances (1)
19
Q
What is meant by vascular bundle? (1)
A
- Xylem and Phloem vessels grouped within the plant stem
(1)
20
Q
What adds structure to the vascular bundle? (1)
A
- Sclerenchyma (1)
21
Q
Function of xylem vessels? (2)
A
- Transports water and mineral ions (1)
- From roots to the rest of the plant (1)
22
Q
Structure of xylem vessels (8)
A
- Dead hollow cells with no end cell walls to form one
continuous tube (2) - No cytoplasm for more space for transporting water (2)
- Wall contains lignin to provide structural support (2)
- Contains pits for mineral ions and water to move in and out
the vessel (2)
23
Q
Function of phloem vessels (3)
A
- Transports dissolved substances such as sucrose and
amino acids (1) - From sources from sinks (1)
- sources = leaves
sinks = roots
(1)
24
Q
What types of cells make up phloem vessels (3)
A
- Sieve tube elements (1)
- Companion cells (1)
- Connected by plasmodesmata (1)
25
Structure of sieve tube elements (4)
- Living cells that join end to end to form sieve tubes (1)
- Ends have sieve plates to allow solutes to pass through (1)
- No organelles and little cytoplasm allows for more solute
transport (1)
- Cant survive on their own with no nucleus (1)
26
Structure of companion cells (2)
- Allows for sieve tube elements to survive with nucleus (1)
- Packed with mitochondria for active loading of sucrose into
sieve tube elements (1)
27
How would you dissect plant stems to view vascular bundle? (4)
- Cut a thin section of plant sample away from you using a
scalpel (1)
- Place sample into water to prevent drying (1)
- Place into dish containing stain (1)
- Rinse sample in water and place onto microscope slide (1)
28
Why is osmosis always occurring in the root hair cells? (1)
- Water is constantly lost in the leaves through transpiration
(1)
29
What the water passes to reach the xylem? (3)
- Moves into the root hair cells by osmosis (1)
- Moves through root cortex (1)
- Then the endodermis (1)
30
The pathways the water can take to reach the xylem? (4)
- Symplast pathway (1)
- Movement through cytoplasm and plasmodesmata (1)
- Apoplast pathway (1)
- Movement through the cell walls (1)
31
Why apoplast pathway is the most common for water transport (1)
- Plant cell walls are very absorbent and water can travel
through them easily (1)
32
Function of the casparian strip in the roots? (3)
- Waxy strip in cell wall thats impermeable in water (1)
- Forces the water in apoplast pathway to enter cell
membrane (1)
- Ensuring no toxic substances enter the xylem (1)
33
How is the water in xylem able to move upwards? (3)
- Tension created by transpiration (1)
- Cohesion is caused by hydrogen bonds creating a column
of water (1)
- Once tension pulls the water up the xylem, the column of
water moves with it (1)
34
What is transpiration and when does it occur? (2)
- Loss of water through evaporation from a plants surface (1)
- Happens in the stomata when gas exchange for
photosynthesis occurs (1)
35
Factors that affect rate of transpiration? (8)
- Light intensity increase rate (1)
- More photosynthesis will occur, therefore, more gas
exchange (1)
- Temperature increases rate (1)
- More kinetic energy means water molecules diffuse out
the stomata faster, increasing water potential gradient (1)
- Wind increases rate (1)
- Will blow away water molecules that have just diffused
out and will increase water potential gradient (1)
- Humidity decreases rate (1)
- more humidity surrounding the air will lower the water
potential gradient (1)
36
How to investigate transpiration and the limitations of the method (3)
- Potometer to measure the amount of water uptake (1)
- Not 100% equal to water loss by transpiration as some
water will be kept and used for photosynthesis and
respiration (1)
37
Method for measuring transpiration rate (6)
- Cut off a shoot underwater to prevent air from entering
xylem (1)
- Enter into potometer still underwater (1)
- Remove potometer from the water with capillary tube still
submerged into the water (1)
- Dry leaves and leave shoot for 30 minutes to acclimatise (1)
- Remove end of capillary tube from beaker until an air
bubble has formed (1)
- Record the distance of bubble movement and work out
time which will estimate rate of transpiration (1)
38
Why is the shoot in the potometer cut at a slant? (1)
- Increases the amount of surface area for water uptake (1)
39
What are xerophytes? (1)
- Plants adapted to living in conditions with no water (1)
40
Adaptations of xerophytes? (6)
- Waxy layer on epidermis reduces evaporation on the
surface (1)
- Sunken stomata reduces the effect of wind, therefore
reducing water potential gradient (1)
- Hairs on epidermis and rolled leaves traps water vapour,
therefore reducing water potential gradient (2)
- Spines instead of leaves reduces surface area for water loss
(1)
- Closure of stomata during high temperature to reduce
average gas exchange (1)
41
Adaptations of hydrophytes (4)
Overall hydrophytes have low levels of oxygen so:
- Air spaces (1)
- Allow for the plant to float and used to store oxygen (1)
- Flexible leaves (1)
- To not be swept by water currents (1)
42
What is translocation? (1)
- Movement of dissolved substances such as sucrose and
amino acids (1)
- Active process (1)
(Takes place in phloem vessels)
43
What happens when sucrose enters a sink? (2)
- Converted into starch for carbohydrate storage (1)
- Maintains a concentration gradient between source and
sink (1)
44
What is the mass flow hypothesis? (1)
- Attempts to explain how solutes are transported from
source to sink in the phloem (1)
45
What are the steps of mass flow? (5)
- Sucrose moves from companion cells to sieve tube
elements by active transport (1)
- This decreases the water potential in the sieve tube
elements causing water to enter the phloem by osmosis (1)
- This increases hydrostatic pressure in the source, causing a
pressure gradient between source and sink (1)
- Solutes will move into sink and convert into other
molecules, increasing water potential at sink (1)
- Water will move out of phloem by osmosis, maintaining the
hydrostatic pressure gradient between source and sink (1)
46
Whats meant by an open circulatory system? (2)
- Blood isn't enclosed in blood vessels (1)
- E.G. Insects (1)
47
Whats meant by closed circulatory system? (2)
- Blood is enclosed in blood vessels (1)
- E.G. Fish and Mammals (1)
48
What is meant by single circulation? (2)
- One loop passing the heart once (1)
- E.G. Fish (1)
49
What is meant by double circulation? (2)
- Two loops passing the heart twice (1)
- E.G. Mammals (1)
50
Structure of Arteries (3)
- Thick muscular wall (1)
- Lots of elastic tissue (1)
- Small lumen (1)
51
Structure of veins (3)
- Large Lumen (1)
- Little elastic tissue (1)
- Valves preventing backflow (1)
52
What is tissue fluid? (2)
- Fluid that comes from the substances that leak out the
capillaries (1)
- Facilitates the exchange between cells and blood (1)
53
How is tissue fluid formed? (2)
- High hydrostatic pressure in the arteriole end of the
capillaries (1)
- Forces fluid down the pressure gradient (1)
54
How is tissue fluid returned? (2)
- Lower water potential in venule
end lowers hydrostatic
pressure (1)
- Osmotic pressure larger than
hydrostatic pressure pulls
water back (1)
55
What happens when blood pressure is high? (hypertension) (3)
- The pressure at the arterial end
is higher than normal (1)
- More tissue fluid pushed out
and accumulated (1)
- Oedema (1)
56
Function of the lymphatic system? (3)
- Larger molecules returned to
the circulatory system as lymph
(1)
- Through compression by body
movement (1)
- At veins close to the heart (1)
57
Function of Aorta? (2)
- Artery (1)
- Transports oxygenated blood
to the rest of the body (1)
58
Function of the Pulmonary Artery? (2)
- Artery (1)
- Transports deoxygenated
blood to the lungs (1)
59
Function of Vena Cava? (2)
- Vein (1)
- Transports blood back into the
right side of the heart (1)
60
Function of Pulmonary Vein? (2)
- Vein (1)
- Transports oxygenated blood
from the lungs to the heart (1)
61
Function of Coronary Arteries? (1)
- The heart muscles own blood
supply (1)
62
What is the cardiac cycle and the steps involved? (4)
- Coordinated sequence of
contractions and relaxations
that cause blood flow (1)
- Atrial systole
- Ventricular systole
- Diastole
63
What happens in atrial systole? (3)
- Atria contracts while ventricle
relaxes (1)
- Decreases atrial volume and
therefore increases pressure
(1)
- This forces atrioventricular
valves to open and pushes
blood into ventricles (1)
64
What happens in ventricular systole? (4)
- Ventricles contract and atria
relaxes (1)
- Decreases ventricular volume
and therefore increases
pressure (1)
- Forces semi-lunar valves to
open and atrioventricular
valves to close (1)
- Blood moves into the arteries
(1)
65
What happens in Diastole? (3)
- Both the atria and ventricles
are relaxed (1)
- This lowers pressure, and is
now higher in arteries (1)
- Forces semi-lunar valves to
close as blood is returned to
the heart to restart cycle (1)
66
Feature of cardiac muscle? (2)
- Myogenic (1)
- Contracts without nerve
impulses (1)
67
How does myogenic contraction occur? (4)
- SAN causes both atria to contract (1)
- SAN depolarises the AVN (1)
- AVN depolarises the bundle of his to cause delay (1)
- Bundle of His depolarise Purkyne fibres to contract both ventricles (1)
68
What is the electrocardiograph made up of? (3)
- P wave shows atrial contraction (1)
- QRS complex shows ventricular contraction (1)
- T wave shows repolarisation of ventricles (1)
69
What are all ECG problems? (4)
Tachycardia = Fast heart rate (1)
Bradycardia = Slow heart rate (1)
Ectopic Heartbeat = Extra heartbeats (1)
Fibrillation = Lack of rhythm (1)
70
Why does haemoglobin have high affinity in the lungs? (3)
- High partial pressure of oxygen in the lungs (1)
- Which means concentration of oxygen (1)
- Affinity means it binds more strongly (1)
71
What happens at respiring tissues? (2)
- Low affinity and partial pressure of oxygen (1)
- Oxyhaemoglobin will deposit oxygen to allow for respiration (1)
72
Why is the dissociation curve S-shaped? (2)
- First oxygen binding causes the oxygen binding sites to uncover (1)
- Hard to bind at end of curve as 3/4 oxygen binding sites are bound (1)
73
What happens during fetal haemoglobin? (3)
- Dissociation curve slightly to the left (1)
- Higher affinity for oxygen (1)
- Still oxyhaemoglobin form by the time it reaches placenta (1)
74
What happens during Bohr effect? (3)
- High CO2 Partial Pressure decreases oxygen affinity (1)
- Ensures oxygen is unloaded at respiring tissues where high CO2 is a product (1)
- High CO2 shifts curve to the right (1)
75
What is the chloride shift? (2)
- Facilitates the Bohr effect (1)
- By promoting haemoglobin unloading oxygen (1)
76
Explain the chloride shift? (6)
- CO2 from respiring cells reacts with water in blood to form carbonic acid (1)
- Carbonic acid dissociates to form H+ and HCO3- (1)
- Increased acidity causes oxyhaemoglobin to unload its oxygen (1)
- Chloride ions diffuse into blood to balance charge (1)
- HCO3- are transported to lungs in blood plasma (1)
- Haemoglobonic acid is formed and is transported to lungs and recombines with HCO3- to produce CO2 to be diffused out (1)
77
Why can heart rate be lower in someone fit? (2)
- Larger ventricle chamber (1)
- Stronger heart muscle (1)
