Nutrition Flashcards
1
Q
Nutrition
A
The series of processes by which living organisms obtain food substances and use them to provide energy and materials for their growth
2
Q
Food
A
Complex energy-rich organic matter which living organisms feed on to obtain nutrients
3
Q
Green plants
A
The earth’s most important food producers.
4
Q
Photosynthesis and mineral salts
A
Essential nutritional processes for green plants.
5
Q
Photosynthesis
A
The process by which green plants manufacture food.
6
Q
Importance of Photosynthesis
A
Important not only to plants themselves but also to animals
7
Q
Where Photosynthesis takes place
A
In the chloroplasts of plant cells
8
Q
Raw materials of Photosynthesis
A
Low-energy containing inorganic compounds
9
Q
Final products of Photosynthesis
A
High-energy containing sugars (organic compounds).
10
Q
By-product of Photosynthesis
A
Oxygen.
11
Q
Energy needed for Photosynthesis
A
Comes from the sunlight absorbed by chlorophyll
12
Q
Movement of gases
A
Carbon dioxide and oxygen
13
Q
Water
A
Enters the root hairs from the soil by osmosis.
14
Q
Movement of water
A
From the root hairs
15
Q
Sugars
A
Most of the sugars produced are changed into starch in the leaf cells.
16
Q
Starch
A
Sugars are stored in this insoluble form until night-time.
17
Q
Translocation
A
The movement of sugars from starch converted back into sugars (soluble form) to be transported to other parts of the plant where they are needed.
18
Q
Use of sugars in cells
A
Source of energy.
19
Q
Special storage organs
A
Some plants have these where the sugar is converted back to starch to be stored for long periods of time.
20
Q
Storage organs examples
A
May be roots
21
Q
Living things
A
All living things are interrelated through their need for food.
22
Q
Starch test
A
Iodine gives a blue-black coloration.
23
Q
Starch-iodine complex
A
The blue-black coloration is due to this formation (which dissociates when heated).
24
Q
Leaf test
A
A leaf
25
Control experiment
A control experiment is done by plucking a leaf before sunrise and testing it for starch. This leaf does not contain starch
26
Oxygen test
A water plant Elodea is placed in a beaker of water and the apparatus
27
Oxygen test control experiment
A control experiment is set up in a similar way but placed in a dark cupboard.
28
Sunlight experiment
This experiment is performed with a fresh green leaf which is still attached to the parent plant (fig. 3-1C). In this way
29
Carbon dioxide experiment
A leaf attached to a potted plant is used for this experiment. The leaf is enclosed in a flask containing caustic soda (sodium hydroxide) solution (fig. 3-1D). This solution absorbs carbon dioxide. The flask is smeared with vaseline at the neck so that it is air-tight. The experiment is set up early in the morning and exposed to bright sunlight for 4-6 hours. The leaf is then detached and tested for starch. Starch will be found to be absent. At the same time
30
Chlorophyll experiment
Take a variegated leaf (a leaf from Coleus
31
Water experiment
Take a potted plant and get it well watered. Keep the potted plant in a dark cupboard for at least 24 hours or overnight so as to destarch the leaves. A leaf sample is tested for starch. Negative result or yellowish-brown colour of the leaf shows absence of starch
32
Photosynthesis stages
Light stage/Light reaction and Dark stage/Dark reaction.
33
Dark Stage/Dark Reaction
This is called dark reactions because it does not require light energy. Carbon dioxide is reduced by combining with atoms of hydrogen provided by the enzyme $NADP_{2}$ to form sugar. This takes place through a series of small steps. Each step is controlled by specific enzyme. The energy needed for the formation of sugar is provided by the ATP which was formed during the light stage (Reduction of $CO_{2}$ to form sugar).
34
Light Reactions/stages
This is called light reactions because it occurs in the light. In the light reaction 4 major steps are involved. The are: Chlorophyll is Energized: The chlorophyll traps
35
Where reactions take place
All reactions that take place in the light stage occur in the grana in the chloroplast. All reactions that take place in the dark stage occur in the stroma in the chloroplast.
36
Leaf
Although all the green parts of a plant can carry out photosynthesis
37
Leaf structure
As such
38
Table 3-1
The main structural adaptations of a leaf to photosynthesis.
39
Chloroplasts
In bright sunlight
40
Fate of Photosynthetic Products
The energy-rich products of photosynthesis (food) are used by plants: • as a source of energy for their activities
41
Glucose
For example
42
Importance of Photosynthesis to Life
Photosynthesis is very important in food cycles as it is the only process that can tap the sun's enormous energy supply. Animals and other heterotrophs cannot make use of the sun's energy and simple substances to manufacture energy-rich food. Therefore
43
Mineral Nutrition in Plants
Plants can make glucose and other carbohydrates from carbon dioxide and water. In addition
44
Nitrification
The process by which decomposers convert organic nitrogen to ammonia and then to nitrites and nitrates.
45
Nitrifying bacteria
Bacteria that carry out nitrification.
46
Nitosomonas
Convert ammonium compounds to nitrites.
47
Nitrobacter
Convert nitrites to nitrates.
48
Denitrification
The process by which denitrifying bacteria in the soil break down nitrates to obtain oxygen for respiration and release nitrogen gas into the atmosphere.
49
Denitrifying bacteria examples
Pseudomonas fluorescens and Pseudomonas denitrificans
50
Nitrogen cycle importance
The nitrogen cycle is important because it makes nitrogen available to plants. Plants cannot absorb nitrogen gas from the atmosphere
51
Human activities effect on Nitrogen cycle
Human activities such as the use of fertilizers and the burning of fossil fuels have increased the amount of nitrogen in the environment. This can lead to problems such as water pollution and acid rain.
52
Food
Complex energy-rich organic matter which living organisms feed on to obtain nutrients
53
Green plants
The earth's most important food producers.
54
Photosynthesis
The process by which green plants manufacture food.
55
Importance of Photosynthesis
Important not only to plants themselves but also to animals
56
Where Photosynthesis takes place
In the chloroplasts of plant cells
57
Raw materials of Photosynthesis
Low-energy containing inorganic compounds
58
Final products of Photosynthesis
High-energy containing sugars (organic compounds).
59
By-product of Photosynthesis
Oxygen.
60
Energy needed for Photosynthesis
Comes from the sunlight absorbed by chlorophyll
61
Movement of gases
Carbon dioxide and oxygen
62
Water
Enters the root hairs from the soil by osmosis.
63
Movement of water
From the root hairs
64
Sugars
Most of the sugars produced are changed into starch in the leaf cells.
65
Starch
Sugars are stored in this insoluble form until night-time.
66
Translocation
The movement of sugars from starch converted back into sugars (soluble form) to be transported to other parts of the plant where they are needed.
67
Use of sugars in cells
Source of energy.
68
Special storage organs
Some plants have these where the sugar is converted back to starch to be stored for long periods of time.
69
Storage organs examples
May be roots
70
71
Starch test
Iodine gives a blue-black coloration.
72
Starch-iodine complex
The blue-black coloration is due to this formation (which dissociates when heated).
73
Leaf test
A leaf
74
Control experiment
A control experiment is done by plucking a leaf before sunrise and testing it for starch. This leaf does not contain starch
75
Oxygen test
A water plant Elodea is placed in a beaker of water and the apparatus
76
Sunlight experiment
This experiment is performed with a fresh green leaf which is still attached to the parent plant (fig. 3-1C). In this way
77
Carbon dioxide experiment
A leaf attached to a potted plant is used for this experiment. The leaf is enclosed in a flask containing caustic soda (sodium hydroxide) solution (fig. 3-1D). This solution absorbs carbon dioxide. The flask is smeared with vaseline at the neck so that it is air-tight. The experiment is set up early in the morning and exposed to bright sunlight for 4-6 hours. The leaf is then detached and tested for starch. Starch will be found to be absent. At the same time
78
Chlorophyll experiment
Take a variegated leaf (a leaf from Coleus
79
Water experiment
Take a potted plant and get it well watered. Keep the potted plant in a dark cupboard for at least 24 hours or overnight so as to destarch the leaves. A leaf sample is tested for starch. Negative result or yellowish-brown colour of the leaf shows absence of starch
80
Photosynthesis stages
Light stage/Light reaction and Dark stage/Dark reaction.
81
Dark Stage/Dark Reaction
This is called dark reactions because it does not require light energy. Carbon dioxide is reduced by combining with atoms of hydrogen provided by the enzyme $NADP_{2}$ to form sugar. This takes place through a series of small steps. Each step is controlled by specific enzyme. The energy needed for the formation of sugar is provided by the ATP which was formed during the light stage (Reduction of $CO_{2}$ to form sugar).
82
Where reactions take place
All reactions that take place in the light stage occur in the grana in the chloroplast. All reactions that take place in the dark stage occur in the stroma in the chloroplast.
83
Light Reactions/stages
This is called light reactions because it occurs in the light. In the light reaction 4 major steps are involved. The are: Chlorophyll is Energized: The chlorophyll traps
84
Leaf
Although all the green parts of a plant can carry out photosynthesis
85
Leaf structure
As such
86
Leaf stalk
Able to hold leaf blade in the best position to receive maximum amount of sunlight
87
Leaf blade
Large surface area for receiving sunlight; thin structure to ensure that the carbon dioxide that enters the leaf can rapidly reach each leaf cell by diffusion
88
Stomata
Present on leaf surface in large numbers to allow entry and exit of gases and water vapour from leaf
89
Intercellular spaces
Present throughout leaf
90
Transport tissue
Well distributed throughout leaf to bring water to each photosynthetic cell and remove manufactured food from it
91
Mesophyll tissue
Cells
92
Death of plants
The dead remains of plants and animals contain complex organic compounds.
93
Putrefaction
The dead remains of plants and animals are acted upon by decomposers such as bacteria and fungi
94
Ammonification
The conversion of organic nitrogen to ammonia.
95
Nitrification
Ammonium compounds are converted to nitrites and then to nitrates by nitrifying bacteria in the soil.
96
Nitrifying bacteria
Bacteria that convert ammonium compounds to nitrites and then to nitrates.
97
Nitrosomonas
Convert ammonium compounds to nitrites.
98
Nitrobacter
Convert nitrites to nitrates.
99
Assimilation
Nitrates dissolve in soil water and are absorbed by plants to make plant proteins.
100
Consumption
Herbivores feed on plants
101
Excretion
Animals excrete nitrogenous waste products such as urea and uric acid.
102
Denitrification
Denitrifying bacteria in the soil break down nitrates to obtain oxygen for respiration and release nitrogen gas into the atmosphere.
103
Denitrifying bacteria examples
Pseudomonas fluorescens and Pseudomonas denitrificans
104
Nitrogen cycle importance
The nitrogen cycle is important because it makes nitrogen available to plants. Plants cannot absorb nitrogen gas from the atmosphere
105
Human activities effect on Nitrogen cycle
Human activities such as the use of fertilizers and the burning of fossil fuels have increased the amount of nitrogen in the environment. This can lead to problems such as water pollution and acid rain.
