Organising Animals And Plants Flashcards
(126 cards)
1
Q
What percentage of blood is made up of plasma?
A
55%
2
Q
What components make up the blood?
A
- Plasma, 55%
- Red blood cells, 45%
- White blood cells, <1%
- Platelets, <1%
3
Q
What is the primary function of blood plasma?
A
Carries dissolved substances around the body
4
Q
What waste product does blood plasma carry to the lungs?
A
Carbon dioxide
5
Q
Where is urea formed and where is it carried to be removed from the blood?
A
Formed in liver, carried to kidneys
6
Q
What do small soluble products of digestion get transported to?
A
Individual cells
7
Q
What is the main function of red blood cells?
A
Pick up oxygen from the air in lungs and carry it to cells
8
Q
What structural adaptation do red blood cells have to increase diffusion?
A
Biconcave disks
9
Q
What pigment do red blood cells contain that binds to oxygen?
A
Haemoglobin
10
Q
Why do red blood cells not have a nucleus?
A
To have more space for haemoglobin
11
Q
What is the role of white blood cells in the body?
A
Form part of the body’s defence system against harmful microorganisms
12
Q
What do lymphocytes produce in response to microorganisms?
A
Antibodies
13
Q
What do some white blood cells form to combat poisons?
A
Antitoxins
14
Q
What process do some white blood cells use to deal with invading bacteria and viruses?
A
Engulf and digest
15
Q
What are platelets and their role in blood?
A
Small fragments of cells important for blood clotting
16
Q
What is the process of blood clotting?
A
Converts fibrinogen into fibrin through enzyme-controlled reactions
17
Q
What does fibrin form when it captures red blood cells and platelets?
A
A clot that dries to form a scab
18
Q
What is the purpose of a scab?
A
Protects new skin as it grows and stops bacteria entering the body
19
Q
What are the three main types of blood vessels?
A
Arteries, veins, capillaries
20
Q
What is the primary function of arteries?
A
Carry blood away from heart to organs
21
Q
What type of blood do arteries carry?
A
Bright-red oxygenated blood
22
Q
Describe the appearance of arteries.
A
Thick walls containing muscle and elastic fibres, small lumen
23
Q
How do arteries facilitate blood movement?
A
Arteries stretch and blood is forced through them, returning to shape, felt as a pulse
24
Q
What is the primary function of veins?
A
Carry blood away from organs towards heart
25
What type of blood do veins carry?
Low in oxygen blood
26
Describe the structure of veins.
Thinner walls, large lumen, have valves
27
How do veins assist in blood flow back to the heart?
Squeezed by skeletal muscles
28
What is the primary function of capillaries?
Link arteries and veins
29
What type of blood do capillaries carry?
Both oxygenated and deoxygenated blood
30
Describe the structure of capillaries.
Tiny vessels with a narrow lumen, walls a single cell thick
31
What process do capillaries enable?
Diffusion in and out of blood from cells
32
What is double circulation?
Blood vessels arranged into a system that carries blood from the heart to the lungs and back, and from the heart to other organs and back
33
Why is double circulation vital for warm-blooded, active animals?
It makes the circulatory system very efficient
34
What happens to fully oxygenated blood after it returns to the heart from the lungs?
It can be sent off to different parts of the body at high pressure
35
Fill in the blank: The walls of capillaries are _______.
a single cell thick
36
True or False: Veins have valves to prevent backflow of blood.
True
37
What is the role of valves in veins?
Prevent backflow of blood
38
What is the primary function of the heart?
The heart pumps blood around the body
## Footnote
The heart is made of two pumps for double circulation.
39
What are the walls of the heart primarily made of?
Muscle
## Footnote
The muscle is supplied with oxygen by the coronary arteries.
40
How many sides does the heart have and what is their function?
Two sides, fill and empty at the same time
## Footnote
This gives a strong coordinated heartbeat.
41
What type of blood enters the right atrium?
Deoxygenated blood
## Footnote
It comes from the body via the vena cava.
42
What type of blood enters the left atrium?
Oxygenated blood
## Footnote
It comes from the lungs via the pulmonary vein.
43
What happens when the atria contract?
They force blood down into the ventricles
## Footnote
Valves close to prevent blood flowing backwards.
44
Which ventricle pumps deoxygenated blood to the lungs?
Right ventricle
## Footnote
It does this through the pulmonary artery.
45
Which ventricle pumps oxygenated blood around the body?
Left ventricle
## Footnote
It does this through the aorta.
46
What creates the sound heard through a stethoscope when the heart beats?
The closing of the heart valves
## Footnote
This prevents blood from flowing backwards.
47
Why is the muscle wall of the left ventricle thicker than that of the right?
To develop the pressure needed to force blood through the arterial system
## Footnote
This allows for circulation all over the body.
48
What condition occurs when the coronary arteries become narrow?
Coronary heart disease
## Footnote
This is due to a buildup of fatty material on the lining of the vessels.
49
What happens if blood flow through the coronary arteries is reduced?
The supply of oxygen to the heart muscle is reduced, causing pain and a heart attack.
50
What is a stent?
A metal mesh placed in the artery to open up the blood vessel
## Footnote
It is inflated by a balloon and remains in place after deflation.
51
What is the purpose of bypass surgery?
To replace narrow/blocked coronary arteries with veins from other parts of the body
## Footnote
This is effective for badly blocked arteries where stents cannot help.
52
What do statins do?
Reduce blood cholesterol levels
## Footnote
They slow down the rate of fatty material deposition in the coronary arteries.
53
True or False: Stents can release drugs to prevent blood clotting.
True
54
Fill in the blank: The left ventricle pumps blood through the _______.
aorta
55
Fill in the blank: Coronary heart disease is caused by a buildup of _______ on the lining of the vessels.
fatty material
56
What happens to heart valves that leak or become stiff?
They make the heart less efficient and can lead to death without treatment.
57
What are the two types of heart valves that can be used for replacement?
* Mechanical
* Biological
58
What materials are mechanical heart valves made of?
Titanium and polymers
59
What is a disadvantage of mechanical heart valves?
Medicine needs to be taken to prevent blood clotting around it.
60
Where do biological heart valves come from?
* Animals (e.g., pigs)
* Human donors
61
What is a key advantage of biological heart valves?
The patient does not need medication.
62
How long do biological heart valves typically last?
12-15 years
63
What is the role of the natural pacemaker in the heart?
To regulate the heart's rhythm and ensure adequate oxygen supply.
64
What can happen if the natural pacemaker stops working properly?
The person may not get enough oxygen or cannot pump blood properly.
65
What is an artificial pacemaker used for?
To correct irregularities in the heart rate.
66
How is an artificial pacemaker implanted?
It is implanted into the chest and attaches two wires to the heart.
67
What does a pacemaker do when the heart rate is too slow?
It sends strong, regular electrical signals to stimulate the heart to beat properly.
68
What is a necessary follow-up after a pacemaker is fitted?
Regular medical check-ups throughout life.
69
What is the purpose of artificial hearts?
To support the natural heart until it can be replaced.
70
What is required for a heart transplant?
A tissue match with the donor heart.
71
What is a risk associated with artificial hearts?
Blood clotting which can lead to death.
72
What can artificial hearts be used for besides replacement?
To give a diseased heart a rest for recovery.
73
What is a disadvantage of developing artificial hearts?
The resources and cost of each one mean they are not widely used.
74
What maintains a steep concentration gradient in the gas exchange system?
Changing the composition of air in the lungs regularly
## Footnote
This allows oxygen to diffuse into the blood and carbon dioxide to diffuse out.
75
What is the process of moving air in and out of the lungs called?
Ventilating the lungs or breathing
## Footnote
This process is crucial for gas exchange.
76
What protects the lungs and separates them from digestive organs?
The ribcage and diaphragm
## Footnote
The diaphragm is a strong sheet of muscle.
77
What muscles are involved in the contraction and relaxation during breathing?
Intercostal muscles
## Footnote
These muscles are located between the ribs and diaphragm.
78
What happens to the ribs and diaphragm when breathing out?
Ribs fall, diaphragm moves up
## Footnote
This decreases the volume of the chest.
79
What is the result of decreased volume in the chest during exhalation?
Increased pressure in the chest
## Footnote
This causes air to be forced out of the lungs.
80
What occurs during inhalation regarding chest volume and pressure?
Volume increases, pressure decreases
## Footnote
Atmospheric air is at higher pressure than the chest, drawing air in.
81
What type of air moves into the lungs when breathing in?
Oxygen-rich air
## Footnote
This maintains a steep concentration gradient for diffusion.
82
What is the role of the alveoli in gas exchange?
Provide a large surface area for diffusion
## Footnote
This is essential for effective gas exchange.
83
How do rich blood capillaries assist in gas exchange?
Maintain a concentration gradient in both directions
## Footnote
Blood coming to the lungs is low in oxygen and high in carbon dioxide.
84
What is the significance of capillaries being one cell thick?
Shortest possible distance for diffusion
## Footnote
This facilitates rapid gas exchange.
85
Fill in the blank: Gas exchange takes place down the steepest ______ possible.
Concentration gradient
## Footnote
This ensures rapid and effective exchange.
86
True or False: Breathing out removes carbon dioxide-rich air from the lungs.
True
## Footnote
This maintains a concentration gradient for CO2 to diffuse out.
87
What is the function of epidermal tissue in plants?
Covers the surface, protects them, secretes a waxy substance that waterproofs the surface of the leaf
## Footnote
Epidermal tissue is essential for reducing water loss in plants.
88
Where does photosynthesis occur in plants?
Palisade mesophyll tissue contains chloroplasts where photosynthesis occurs
## Footnote
Palisade mesophyll is usually located beneath the epidermis in leaves.
89
What is the role of spongy mesophyll tissue?
Contains some chloroplasts for photosynthesis, big air spaces, and large surface area to make diffusion of gases easier
## Footnote
This tissue helps facilitate gas exchange in leaves.
90
What does xylem transport?
Water and dissolved mineral ions from roots to the leaves
## Footnote
Xylem is essential for maintaining plant hydration and nutrient supply.
91
What is the function of phloem?
Carries dissolved food from leaves around the plant
## Footnote
Phloem is critical for distributing energy sources to all parts of the plant.
92
What is meristem tissue?
Tissue made of plant cells that grow and differentiate into all cell types needed
## Footnote
Meristematic tissue is crucial for plant growth and development.
93
What is the primary function of leaves in a plant?
Carries out photosynthesis
## Footnote
Leaves are the main sites for light absorption and gas exchange.
94
What role do stems play in a plant?
Supports leaves and flowers
## Footnote
Stems also facilitate the transport of fluids between roots and leaves.
95
What is the main function of roots?
Take up water and mineral ions from the soil
## Footnote
Roots also anchor the plant and can store energy.
96
What forms an organ system in plants?
The whole body of a plant for the transport of substances around the plant
## Footnote
This system involves collaboration among different organs and tissues.
97
What is the primary function of phloem in plants?
Transports the sugars made by photosynthesis from leaves to the rest of the plant
## Footnote
Sugars are used as energy stores or for making new cells in growing areas.
98
What is the term for the movement of dissolved sugars from the leaves to the rest of the plant?
Translocation
## Footnote
This process is crucial for distributing energy throughout the plant.
99
What effect do aphids have on phloem?
They destroy the phloem and feed on the sugary fluid
## Footnote
This feeding can kill the plant by depleting its food supply.
100
What is the primary function of xylem in plants?
Carries water and mineral ions from the soil to the stem and leaves
## Footnote
Mature xylem cells are dead, facilitating this transport.
101
Why is transport important in plants?
Food made by photosynthesis is needed for respiration and growth
## Footnote
Water and mineral ions are essential for protein production and other cellular processes.
102
What role does water play in maintaining plant structure?
It helps hold the plant upright by creating pressure in the vacuole
## Footnote
This pressure against the cell walls provides support and structure to leaves.
103
Fill in the blank: The movement of water and mineral ions is crucial for the production of _______.
proteins and other molecules
## Footnote
These components are vital for various cellular functions.
104
True or False: All xylem cells in mature plants are alive.
False
## Footnote
Mature xylem cells are actually dead.
105
What is the primary function of stomata in plants?
To allow air into the leaves for gas exchange
## Footnote
Stomata facilitate the diffusion of carbon dioxide and oxygen.
106
What process allows water to enter the root hair cell?
Osmosis
## Footnote
Osmosis is the movement of water from high to low concentration through a partially permeable membrane.
107
How do minerals enter the roots of a plant?
Active transport
## Footnote
Active transport requires energy to move substances against the concentration gradient.
108
What is transpiration?
The loss of water vapour from the leaves of a plant
## Footnote
Transpiration occurs through diffusion when stomata are open.
109
What drives the transpiration stream in plants?
Evaporation of water from leaves
## Footnote
The transpiration stream is the continuous movement of water through the xylem from roots to leaves.
110
How does the size of stomata affect water loss?
Larger stomata allow more water vapour to escape
## Footnote
Guard cells control the opening and closing of stomata.
111
Fill in the blank: Water travels up the _______ in plants.
xylem
## Footnote
The xylem is responsible for transporting water from the roots to the leaves.
112
True or False: Transpiration helps maintain a concentration gradient for oxygen diffusion.
True
## Footnote
The loss of water vapour helps maintain the gradient necessary for gas exchange.
113
What happens to the water that evaporates from the leaves?
More water is pulled up through the xylem to take its place
## Footnote
This process is essential for maintaining water levels within the plant.
114
What is the role of guard cells in relation to stomata?
They control the opening and closing of stomata
## Footnote
This regulation is crucial for managing water loss and gas exchange.
115
What is the concentration gradient?
The difference in concentration of a substance between two areas
## Footnote
It drives diffusion processes in plants, including gas exchange.
116
What are the factors that affect the rate of transpiration?
• Temperature
• Humidity and amount of air movement
• Light intensity
## Footnote
These factors influence the rate at which water is lost from plants.
117
How does light intensity affect transpiration?
Increased light intensity leads to increased photosynthesis, causing more stomata to open and thus higher rates of transpiration.
## Footnote
At night, stomata are closed, resulting in little transpiration.
118
What is the effect of temperature on transpiration?
Higher temperatures increase the rate of transpiration as water molecules gain more energy and evaporate faster.
## Footnote
Warmer conditions also promote stomata opening for gas exchange.
119
How does air flow influence transpiration?
High air flow increases the rate of transpiration by quickly blowing away water molecules, raising the concentration gradient.
## Footnote
A higher concentration gradient enhances water diffusion out of the plant.
120
What is the effect of humidity on transpiration?
Increased humidity decreases the rate of transpiration due to a lower concentration gradient for water diffusion.
## Footnote
When the outside air is more humid, less water is lost from the plant.
121
What adaptations do plants have to control water loss?
• Waxy waterproof layer
• Stomata on the underside of leaves
## Footnote
These adaptations help minimize water loss while allowing for photosynthesis.
122
What is wilting in plants, and why does it occur?
Wilting is a protective mechanism against water loss, where leaves collapse and hang down to reduce surface area for evaporation.
## Footnote
This occurs when a plant loses water faster than it can be replenished.
123
What happens to stomata during wilting?
Stomata close to prevent most water loss and further wilting, stopping photosynthesis.
## Footnote
This can risk overheating the plant.
124
What is a potometer used for?
A potometer measures the uptake of water by a plant and gives an idea of the amount of water lost in transpiration.
## Footnote
It consists of a beaker connected to a tube with a ruler, tracking air bubble movement.
125
Fill in the blank: A potometer uses a _______ to measure the water uptake by a plant.
beaker
## Footnote
The setup allows for tracking how much water is lost through transpiration.
126
True or False: Increased light intensity at night increases the rate of transpiration.
False
## Footnote
At night, stomata are closed, leading to little to no transpiration.
