Organisation Flashcards
1
Q
cells are …
A
the fundamental units of all living organisms.
2
Q
tissues in the stomach
A
epithelial
glandular
muscular
3
Q
Organs are groups of distinct tissues that work together to perform a specific _____.
A
function
4
Q
Tissues that make up the stomach: epithelial
A
Lines the stomach.
5
Q
Tissues that make up the stomach: muscular
A
Moves around the contents of the stomach.
6
Q
Tissues that make up the stomach: glandular
A
Produces digestive juices that break down the contents.
7
Q
The digestive system is made up of:
A
stomach
large and small intestine
liver
glands
8
Q
role of the stomach
A
Digests food.
9
Q
role of the large intestine
A
absorbs water molecules from the remaining undigested foods, producing faeces
10
Q
role of the small intestine
A
digests food and absorbs soluble food molecules
11
Q
role of the liver
A
produces bile
12
Q
role of the glands
A
produces digestive juices
13
Q
Order the levels of organisation (in multicellular organisms) from least to most complex
A
1) , cell
2) . tissue
3) . organ
4) . organ system
5) . organism
14
Q
Enzyme Activity
A
The substrate binds to the active site of an enzyme, which has a matching shape. Here, its reaction is sped up. In this case, the molecule is broken down.
15
Q
what describes an enzymes active site
A
catalyses a reaction
binds to the reacting chemical
only fits one substrate
its shape is important
16
Q
What is another name for an enzyme?
A
biological catalyst
17
Q
how does an enzyme denature?
A
Enzymes have an optimum pH (measure of acidity). If the pH changes away from the optimum, then the enzyme activity decreases. If the pH is too low or too high, then the enzyme is denatured
18
Q
Calculating Rate of Reaction
A
The rate of reaction is equal to the gradient of the graph, which shows mass of the product plotted against the reaction time.
The gradient is calculated by picking two points on the graph, then dividing the change in the value on the y axis (mass) by the change in the x axis value (time), between those two points.
19
Q
what is true of the rate of reaction?
A
dependent on the mass of the product
can be calculated
unit is g/s
20
Q
Increasing the temperature of a working enzyme initially increases the activity. Enzymes have an optimum temperature, and once this is reached, the activity ________. Then, past a certain temperature, the active site changes shape, and the enzyme is ________.
A
Increasing the temperature of a working enzyme initially increases the activity. Enzymes have an optimum temperature, and once this is reached, the activity DECREASES. Then, past a certain temperature, the active site changes shape, and the enzyme is DENATURED.
21
Q
Equation for gradients
A
gradient= change in x/change in y
22
Q
Factors influencing rate of reaction:
A
pH and temp
23
Q
Enzymes have an optimum __(measure of acidity). If the __changes away from the optimum pH, then the enzyme activity _______.
A
Enzymes have an optimum pH (measure of acidity). If the pH changes away from the optimum pH, then the enzyme activity DECREASES.
24
Q
Digested molecules are used to construct new:
A
Carbohydrates
proteins
lipids
25
Bile
bile is an alkaline substance produced in the liver and stored in the gallbladder
26
what is true of bile?
alkaline substance
breaks fat
produced in the liver
27
Emulsification
Bile breaks up fats (like oil) into tiny droplets, through a process called emulsification. The tiny droplets have a higher surface area than the original fat drop, which increases the rate of the reactions (catalysed by lipase) that break fats down.
28
Enzymes in the small intestine operate best in alkaline conditions. Bile ________ hydrochloric acid from the stomach to stop these enzymes becoming denatured.
Enzymes in the small intestine operate best in alkaline conditions. Bile NEUTRALISES hydrochloric acid from the stomach to stop these enzymes becoming denatured.
29
Digestive enzymes _____ (speed up) the breakdown of large, _______ food molecules into smaller, soluble molecules.
Digestive enzymes CATALYSE (speed up) the breakdown of large, INSOLUBLE food molecules into smaller, soluble molecules.
30
When amylase breaks down starch, ______ and other sugars are produced.
When amylase breaks down starch, maltose and other sugars are produced.
31
Proteases break down proteins into:
Amino acids
32
Proteases are produced in:
small intestine
pancreas
stomach
33
Action sites for amylase:
small intestine
mouth
34
Proteases break down proteins into their constituent...
amino acids
35
Lipase breaks lipids down...
into fatty acids and glycerol
36
role of the digestive enzyme amylase?
breaks down starch into maltose and other sugars
produced in the small intestine and mouth
37
role of the digestive enzyme lipase?
Break down lipids into glycerol and fatty acids
produced In the small intestine and pancreas
38
role of the digestive enzyme proteases?
Break down proteins into amino acids
produced In small intestine and stomach
39
Tests for various food substances: sugar
Add Benedict’s reagent and heat for about two minutes. It will turn any of green, yellow or red if this food substance is present.
40
Tests for various food substances: starch
Add iodine solution. It will turn blue-black if present.
41
Tests for various food substances: lipids
Add Sudan III. If present, a red-stained oil layer will float on the water surface. Ethanol can also be added and when the solution is shaken, it turns cloudy.
42
Tests for various food substances: proteins
Add Biuret solution. It will turn mauve or purple if present.
43
Reagents used for testing food substances
Sudan III or ethanol
Lipids
Biuret
Proteins
Iodine
Starch
Benedict's
sugar
44
The main types of blood vessel are:
Veins
Arteries
Capillaries
45
role of arteries
takes blood away from the heart
carry oxygenated blood (except for pulmonary artery)
46
an example of a waste product that moves into the blood in capillaries?
Carbon Dioxide
47
Capillaries have thin walls and pass very close to the body cells, which allows _____, _______ and _______ products to be exchanged efficiently
which allows food, oxygen and waste products to be exchanged efficiently.
48
Why do veins have valves?
to prevent backflow of blood
49
Artery walls have thick layers of muscle, making them strong and able to cope with the ______ pressure at which blood is pumped out by the heart.
Artery walls have thick layers of muscle, making them strong and able to cope with the high
pressure at which blood is pumped out by the heart.
50
Therefore, veins have a thinner wall and ______ cross section than arteries. Veins also have _____ to prevent the back flow of blood.
Therefore, veins have a thinner wall and wider cross section than arteries. Veins also have valves to prevent the back flow of blood.
51
Veins
These form when capillaries join back up after passing through the body. They transport blood from the organs back to the heart.
52
Capillaries
Arteries branch into these much smaller vessels. In these blood vessels, food, oxygen and waste products are exchanged between the blood and the body cells.
53
Arteries
Transport blood away from the heart to the organs.
54
What does pulmonary mean?
means anything relating to the lungs.
55
Pulmonary vein's function
The Pulmonary VIEN transports OXYGENATED blood from the lungs to the heart.
56
Pulmonary artery's function
The Pulmonary ARTERY transports DE-OXYGENATED blood from the heart to the lungs.
57
Capillaries..
branch out from arteries
have thin walls
58
The chambers of the heart:
left and right atrium
left and right ventricle
59
Blood enters the heart via the....
atria
60
In the heart:
blood enters via the atria
the atria contract
61
Why might someone be fitted with an artificial pacemaker?
Normally, a group of cells in the right atrium act as a pacemaker to control the heart's beating.
If these cells don't work properly, irregular heart rates can be corrected using electrical devices, known as artificial pacemakers.
62
function of coronary arteries:
The HEART RECIEVS OXYGENATED blood through these arteries.
63
function of aorta:
The heart PUMPS OUT OXYGENATED blood to the BODY through this artery.
64
function of pulmonary artery:
The heart PUMPS OUT DE-OXYGENATED blood to the LUNGS through this artery.
65
functions: Vena cava
The heart RECIEVES DE-OXYGENATED blood FROM the BODY through this vein.
66
functions:Pulmonary vein
The heart receives oxygenated blood from the lungs through this vein.
67
examples of arteries:
coronary
aorta
pulmonary artery
68
examples of veins:
vena cava
pulmonary vein
69
Which blood vessels take blood away from the heart?
Aorta
brachial and pulmonary artery
70
what controls the pumping of the heart.
A group of cells in the right atrium act as a pacemaker, controlling the pumping heart.
71
Which blood vessel supplies the heart muscle with oxygenated blood?
coronary arteries
72
The heart is the ______ organ that pumps blood around the body. It has four chambers: the left and right ___ and the left and right ventricles. It also contains valves and a ________.
The heart is the muscular organ that pumps blood around the body. It has four chambers: the left and right atria and the left and right ventricles. It also contains valves and a pacemaker.
73
A group of cells in the ____ ______ act as a ______.
A group of cells in the right atrium act as a pacemaker.
74
Why is the human circulatory system called a double circulatory system?
because blood passes through the heart twice per circuit.
75
Gas Exchange in the Lungs
1) . de-oxygenated blood arrives to the lungs from the heart
2) . The lungs oxygenate (supply oxygen to) the blood
3) . the blood goes to the heart in the pulmonary vein
76
The alveoli in your lungs have a larger surface area to increase the rate of diffusion of oxygen and carbon dioxide. What else can increase the rate of diffusion?
1) . The concentration gradient - the bigger the difference in concentration between 2 areas, the faster the rate of diffusion.
2) . The temperature - the higher the temperature, the faster the rate of diffusion.
77
The alveoli are tiny air sacs in the ____. They are surrounded by a network of _________, allowing for oxygen and carbon dioxide to be exchanged between the blood in the capillaries and the air in the lungs.
The alveoli are tiny air sacs in the lungs. They are surrounded by a network of capillaries, allowing for oxygen and carbon dioxide to be exchanged between the blood in the capillaries and the air in the lungs.
78
______ and carbon dioxide move between the air and blood by diffusion in the tiny air sacs in the lungs called alveoli.
Oxygen and carbon dioxide move between the air and blood by diffusion in the tiny air sacs in the lungs called alveoli.
79
What would happen if blood didn't pass through the heart twice per circuit?
blood would either not be oxygenated
or wouldn't be pumped around the body
80
________ blood arrives at the lungs from the heart via the pulmonary artery.
Deoxygenated blood arrives at the lungs from the heart via the pulmonary artery.
81
The lungs _________ the blood before it returns to the heart with the pulmonary ____.
The lungs oxygenate the blood before it returns to the heart with the pulmonary vein.
82
How are alveoli adapted for their function?
They are very close to capillaries, so the distance for gases to diffuse is small.
They have a large moist surface area.
They have a rich oxygen supply.
83
The Components of Blood
Blood is made up of a fluid called plasma which has red blood cells, white blood cells
and platelets suspended within it.
84
What is the function of platelets?
triggering blood clotting
They are small cell fragments that do not have a nucleus.
85
what component of blood are small cell fragments that do not have a nucleus.
platelets
86
Blood is a ______, which means it is a group of similar cells that act harmoniously to perform a similar function.
Blood is a tissue, which means it is a group of similar cells that act harmoniously to perform a similar function.
87
what is blood plasma?
a tissue
88
What would happen if red blood cells had a nucleus?
there would be less room for haemoglobin and oxygen
89
Red blood cells have a _______ shape that creates a large ______ area and allows for the rapid diffusion of ______.
Red blood cells have a biconcave shape that creates a large surface area and allows for the rapid diffusion of oxygen.
90
Haemoglobin in Whales
Red blood cells contain haemoglobin, which binds with oxygen in the lungs.
Whales need to store lots of oxygen because they don't breathe when they dive underwater.
Whales have 2x as much haemoglobin in their blood as humans.
91
Why do white blood cells change shape?
To squeeze through the walls of blood vessels into body tissues and to engulf harmful microorganisms.
92
RBC adaptations
binocave shape
haemoglobin
no nucleus
small size
93
what are white blood cells responsible for ?
White blood cells are responsible for defence against infection.
94
red blood cell : binocave shape
This creates a large surface area and allows for the rapid diffusion of oxygen.
95
red blood cell : contains haemoglobin
It contains haemoglobin, which binds with oxygen in the lungs.
96
red blood cell: no nucleus
It does not have a nucleus, which frees up room for haemoglobin.
97
red blood cell: small size
It is small in size, which guarantees passage even through tiny capillaries.
98
WBC characteristics?
can change shape
defends against infection
has a nucleus
99
Types of disease
Non-communicable
Cannot spread between organisms
Communicable
Spread between organisms
100
Why is HIV dangerous?
It can suppress the immune system and makes people more susceptible to catching other infectious diseases.
101
Disease can negatively impact upon an individual’s _____ health, and ______ can be triggered by an immune reaction to pathogens or other substances.
Disease can negatively impact upon an individual’s mental health, and allergies can be triggered by an immune reaction to pathogens or other substances.
102
What are allergies triggered by?
triggered by an immune reaction to pathogens or other substances
103
Factors affecting health
Diet
Stress
Life situations
104
Viruses occupying cells can stimulate ______, e.g. ___ can stimulate cervical cancer.
Viruses occupying cells can stimulate cancers, e.g. HPV can stimulate cervical cancer.
105
what is true of disease interactions?
diet can impact on mental health
HIV suppresses the immune system
viruses occupying cells cause cancers
106
_______ and ________ organisations track cases of diseases, to inform their _______ decisions.
Governments and health organisations track cases of diseases, to inform their policy decisions.
107
Risk factors relating to health:
substances (chemicals from smoking.)
Lifestyle (Unbalanced diet.)
108
Diseases and their proven risk factors are
Brain damage in babies
Excessive alcohol drinking during pregnancy
Cancer
Ionising radiation, which can damage cells
excessive alcohol consumption
Liver and brain damage
109
Why is it important for scientists to scrutinise the links between risk factors and the probability of getting certain diseases?
To ensure that it is actually the risk factor that is causing the disease and not something else altogether.
Finding causal mechanisms is the way to prove a link.
110
Data counted for risk graphs:
incidence of a risk factor
incidence of the disease
111
Which organs can be damaged by excessive alcohol drinking?
brain and liver
112
When considering risk factors, scientific data uses ____.
When considering risk factors, scientific data uses samples.
113
an impact of obesity ?
increased risk of the other diseases
reduced lifestyle options
financial cost for the NHS
114
common types of graphs used for plotting risk factors?
bar charts and scatter graphs
115
Types of Heart Valve Disease
Valves that don't fully open
Obstruct blood flow
leaky valves
Allow back-flow of blood
116
Coronary arteries can become narrowed as a result of a build-up of fatty deposits. As a consequence, _______ _____ is reduced, leading to a ____ ___ _____ being supplied to the heart muscle.
Coronary arteries can become narrowed as a result of a build-up of fatty deposits. As a consequence, blood flow is reduced, leading to a lack of oxygen being supplied to the heart muscle.
117
What procedure may be necessary in the case of heart failure?
transplant of a donor heart
118
Artificial hearts may not be ideal because they can result in long and _______ stays in hospital as well as blood clots. These blood _______ can potentially lead to _______.
Artificial hearts may not be ideal because they can result in long and expensive stays in hospital as well as blood clots. These blood clots can potentially lead to strokes.
119
features of artificial hearts:
risk of blood clots and strokes
unlikely to be rejected
120
Treatments for coronary heart disease:
statins
stents
121
What are the potential disadvantages of using transplanted organs to treat heart disease?
need immunosuppressant drugs
may be rejected
122
___________ drugs are used to stop the patient's ______ system from rejecting a new donor organ.
Immunosuppressant drugs are used to stop the patient's immune system from rejecting a new donor organ.
123
Advantages and Disadvantages of Heart Treatments: drugs
Advantages
Cheap
No surgery
Disadvantages
Side effects
Patients need to remember to take
124
Advantages and Disadvantages of Heart Treatments : Mechanical devices
Advantages
Used when donor isn't available
Disadvantages
Power supply
Can wear out and need replacement
125
Advantages and Disadvantages of Heart Treatments : Transplants
Advantages
Don`t wear out
Function as the replaced organ
Disadvantages
Require suitable donor
Immunosuppressants
126
When a stent is inserted, it ______ the fatty deposit and keeps the _____ open. Over time, the stent _______ the artery wall, so the artery can begin to ______ again as scar ______ builds up.
When a stent is inserted, it compresses the fatty deposit and keeps the artery open. Over time, the stent irritates the artery wall, so the artery can begin to narrow again as scar tissue builds up.
127
Cancer is a group of ________, where changes in cells lead to _______ growth and _______ of cells.
Cancer is a group of diseases, where changes in cells lead to uncontrolled growth and division of cells.
128
Which types of cancer have the following characteristics?
Malignant
Spread throughout the body in the blood, leading to the creation of more secondary tumours.
Benign
Stay in a specific part of the body, often within a membrane.
129
The categories of risk factors for cancer are:
lifestyle
genetic
130
What is cancer?
a group of diseases
131
Why should we always wear sun cream on the beach?
Because increased UV exposure (e.g. through lots of sunbathing) has been identified to increase the risk of some cancers.
132
The types of tumour are:
malignant and benign
133
Some cancers have an increased risk of being ______ from your parents. For example, some genes can cause increased susceptibility (vulnerability) to some types of breast cancer
Some cancers have an increased risk of being inherited from your parents. For example, some genes can cause increased susceptibility to some types of breast cancer
134
Examples of plants organs:
1
Stems
2
Leaves
3
Reproductive structures
4
Roots
135
What are the four main components of plant leaves?
epidermal tissue
stomata
strong mesophyll
palisade mesophyll
136
Stomata
Gaps that facilitate (make easier) the diffusion of gases in and out of the leaf, if they are open.
137
Epidermis
Tissue that covers the outer surface of leaves (as well as the rest of the plant).
138
Palisade mesophyll
Row of cells located below the upper epidermis. They are exposed to a lot of sunlight and so have lots of chloroplasts.
139
Spongy mesophyll
Contains many air spaces, which help with gas exchange throughout the leaf.
140
Transpiration transports:
water
minerals
141
Factors increasing the rate of transpiration:
decreased humidity
increased temp, air flow and light intensity
142
A higher temperature will make more water _______. This will increase the rate of _________.
A higher temperature will make more water evaporate. This will increase the rate of transpiration.
143
what is transpiration (Water Transport)?
Transpiration transports water and the minerals dissolved in it through the plant. Water moves in one direction only - from the roots to the leaves.
144
Increased temperature and light ______ makes water evaporate faster, so it increases the rate of transpiration.
Increased temperature and light intensity makes water evaporate faster, so it increases the rate of transpiration.
145
Factors affecting the rate of transpiration:
temp
air flow
humidity
light intensity
146
Measuring the Rate of Transpiration
The set-up for a potometer is shown here. It is used to measure the rate of transpiration.
As water is lost through the plant’s leaves, the air bubble moves.
The speed of the bubble's movement shows the rate of water uptake.
This is only an estimation (guess) as a small amount of the water taken up by the shoot is used in the leaves.
147
When measuring the rate of transpiration with a potometer, why is the calculation only an estimate?
A small amount of the water taken up by the shoot is used in the leaves and is not transpired.
148
When measuring the rate of transpiration, the speed of the bubble's ______ measures the rate of _____ uptake.
When measuring the rate of transpiration, the speed of the bubble's movement measures the rate of water uptake.
149
What apparatus is used to calculate the rate of transpiration?
potometer
150
When water is lost through the plant’s leaves in a transpiration experiment, the air ______ in the ________ moves.
The speed that the bubble moves indicates the rate of water ______ by the plant.
When water is lost through the plant’s leaves in a transpiration experiment, the air bubble in the potometer moves.
The speed that the bubble moves indicates the rate of water uptake by the plant.
151
what is translocation?
Translocation is the process by which food produced in photosynthesis is transported from the leaves to the growing regions of plants and storage organs.
152
Translocation happens through:
phloem tubes
153
How do transpiration and translocation differ?
Unlike water transport (transpiration), translocation is bidirectional (movement is both up and down the plant).
154
Xylem cells have no end walls, meaning that successive cells form a long ____ for ease of transport.
Xylem cells have no end walls, meaning that successive cells form a long tube for ease of transport.
155
How does lignin help xylem cells perform their function?
Lignin in the cell wall strengthens and waterproofs the elongated cells.
156
Root hair cell adaptions:
mitochondria
long projections
157
Adaptations of xylem cells:
dead cells
no end walls
lignin
158
If water is moving via osmosis, in which direction will it flow?
from a dilute solution to a concentrated one
159
Xylem cells are dead, meaning that the tubes are _____ and, therefore, their resistance to water flow is low.
Xylem cells are dead, meaning that the tubes are hollow and, therefore, their resistance to water flow is low.
160
Root hair cells absorb water from the soil using osmosis (the movement of water from a dilute solution to a concentrated solution). Mineral ions are taken up by active _____.
Root hair cells absorb water from the soil using osmosis (the movement of water from a dilute solution to a concentrated solution). Mineral ions are taken up by active transport.
161
When water is _______ (lots available) the plant can afford to lose water, so it opens the ______ to allow gases for photosynthesis to move freely in and out of the leaf.
When water is abundant (lots available) the plant can afford to lose water, so it opens the stomata to allow gases for photosynthesis to move freely in and out of the leaf.
162
The _____ cells can open the stomata by taking up lots of water, causing them to swell.
The guard cells can open the stomata by taking up lots of water, causing them to swell.
163
The state of stomata (open or closed):
balances allowing gases in and conserving water
164
Stomata are gaps in the lower _________ of leaves that facilitate (make easier) the _______ of gases, including evaporated water, in and out of the leaf.
Stomata are gaps in the lower epidermis of leaves that facilitate (make easier) the diffusion of gases, including evaporated water, in and out of the leaf.
165
To _____ the stomata, the guard cells lose water and return to a limp state.
To close the stomata, the guard cells lose water and return to a limp state.
