Biology Flashcards
(110 cards)
1
Q
What was the main conclusion of Van Helmont’s experiment regarding plant mass?
A
The increase in the plant’s mass was not primarily due to the soil
Van Helmont’s experiment showed that a willow tree gained mass while the soil mass decreased only slightly, suggesting that plants do not solely rely on soil for nutrients.
2
Q
What are the raw materials required for photosynthesis?
A
Carbon dioxide and water
3
Q
What are the products formed during photosynthesis?
A
Glucose and oxygen
4
Q
What is the role of light in photosynthesis?
A
Light is needed for photosynthesis to occur
5
Q
Where does photosynthesis take place within a plant cell?
A
In the chloroplasts
6
Q
What is the word equation for photosynthesis?
A
Carbon dioxide + water → glucose + oxygen
7
Q
How does chlorophyll contribute to photosynthesis?
A
Chlorophyll captures light energy for the process
8
Q
What are two factors that can limit the rate of photosynthesis?
A
Light intensity and carbon dioxide concentration
9
Q
Explain why plants only photosynthesize during the day.
A
Because light is required for photosynthesis
10
Q
What is the word equation for aerobic respiration in plants?
A
Glucose + oxygen → carbon dioxide + water (+ energy)
11
Q
What two substances are required for aerobic respiration?
A
Glucose and oxygen
12
Q
Why do all living cells in a plant need to carry out aerobic respiration?
A
To release energy from glucose
13
Q
What happens to the glucose produced during photosynthesis?
A
It can be used for energy in respiration or converted into starch for storage
14
Q
Why do root cells need a constant supply of oxygen?
A
For aerobic respiration to produce energy
15
Q
What happens to a plant if its roots become waterlogged?
A
The plant may die due to a lack of oxygen for respiration
16
Q
What changes occur in oxygen and carbon dioxide concentrations around a pondweed during the day?
A
Oxygen concentration increases, carbon dioxide concentration decreases
17
Q
What changes occur in oxygen and carbon dioxide concentrations around a pondweed during the night?
A
Oxygen concentration decreases, carbon dioxide concentration increases
18
Q
Identify the structures within a leaf cell where photosynthesis primarily occurs.
A
Chloroplasts
19
Q
What are the two main functions of roots?
A
- Hold the plant firmly in the soil
- Absorb water and dissolved mineral salts
20
Q
What is the significance of nitrogen for plants?
A
It is essential for making proteins
21
Q
How do root hairs adapt to enhance water absorption?
A
They are branched and spread out extensively to increase surface area
22
Q
What is the purpose of leaf stomata?
A
To regulate the exchange of gases and water vapour
23
Q
What adaptations do palisade cells have for photosynthesis?
A
They contain many chloroplasts and can move to optimize light absorption
24
Q
Describe how temperature affects the rate of gas diffusion in leaves.
A
Gas diffusion is faster at higher temperatures
25
What adaptation does the Venus Flytrap have for nutrient acquisition?
It captures and digests insects to obtain nutrients
26
How do root hair cells facilitate the absorption of water?
Water enters root hair cells by osmosis
27
What is the trap mechanism of the Venus flytrap?
The trap mechanism involves sensitive trigger hairs on the inner surface of the lobes; when an insect touches these hairs, the two lobes rapidly snap shut.
28
What are root hair cells and their function?
Root hair cells are long, thin extensions of epidermal cells that increase the surface area of the root for absorbing water and mineral salts.
29
How does water enter root hair cells?
Water enters the root hair cells by osmosis, and dissolved mineral salts are absorbed by active transport.
30
What is the role of xylem vessels in plants?
Xylem vessels form a continuous transport network throughout the plant, carrying water and dissolved mineral salts to the leaves.
31
What happens to plant cells if they do not receive enough water?
If the plant does not receive enough water, its cells will lose turgor, causing the plant to wilt.
32
What are stomata and their function?
Stomata are small openings in the leaf that allow gas exchange, controlled by guard cells.
33
How do guard cells control the size of stomatal openings?
The shape and turgidity of guard cells control the size of the stomatal opening, allowing gas exchange.
34
What is the palisade mesophyll layer?
The palisade mesophyll layer contains cells rich in chloroplasts and is located near the upper surface of the leaf.
35
What is the function of the spongy mesophyll layer?
The spongy mesophyll layer has air spaces that facilitate the diffusion of carbon dioxide throughout the leaf tissue.
36
Why do root cells need oxygen?
Root cells require oxygen for aerobic respiration, which releases energy for growth and the active uptake of minerals and water.
37
What is the overall word equation for photosynthesis?
The overall word equation is carbon dioxide + water → glucose + oxygen.
38
What happens to glucose produced during photosynthesis not immediately used for energy?
It is converted into starch for storage or used to make fats, oils, and proteins.
39
How are root hairs adapted for absorption?
Root hairs have a long, hair-like extension that increases the surface area for more efficient absorption of water and minerals.
40
How does the Venus flytrap obtain essential mineral salts?
It traps and digests insects to absorb necessary mineral salts.
41
How are leaves adapted to capture light energy?
Leaves are broad and wide for a large surface area and have palisade cells packed with chloroplasts near the upper surface.
42
What is the role of stomata in gas exchange?
Stomata allow for the intake of carbon dioxide and release of oxygen, regulated by guard cells.
43
What minerals do plants absorb from the soil to make proteins?
Plants absorb nitrates, which contain nitrogen, to make proteins.
44
What is the role of enzymes in seed germination?
Enzymes break down stored starch into glucose, providing energy for the embryo to grow.
45
Why do farmers use fertilizers?
Fertilizers provide essential mineral salts that help plants grow healthily and increase crop yield.
46
What is cross-breeding in plant breeding?
Cross-breeding involves breeding different plant varieties to create new ones with desired traits.
47
What is one benefit of planting different crop varieties?
It increases biodiversity, reducing the risk of losing the entire crop to disease or pests.
48
How can excess use of fertilizers affect water bodies?
It can lead to algal blooms, which deplete oxygen levels in water, harming aquatic life.
49
What is the role of decomposers in the carbon cycle?
Decomposers break down dead organic matter, releasing carbon dioxide back into the atmosphere.
50
Why do some people prefer organically farmed foods?
They believe organically farmed foods are healthier and better for the environment.
51
How does powdery mildew affect photosynthesis?
It blocks sunlight from reaching chloroplasts, reducing the rate of photosynthesis.
52
What is powdery mildew and how does it affect photosynthesis?
Powdery mildew is a fungal growth that blocks sunlight from reaching chloroplasts in leaf cells, reducing the rate of photosynthesis.
53
What are the major organic compounds produced by plants?
The major organic compounds produced by plants are:
* Carbohydrates
* Lipids
* Proteins
54
What is the primary carbohydrate produced by plants during photosynthesis?
Glucose
55
What can glucose molecules be linked together to form?
Starch
56
How is starch used by plants?
Starch is stored for energy and can be broken down into glucose when needed.
57
How are sugars transported in plants?
Sugars are transported in the form of sucrose through the phloem vessels.
58
What indicates the presence of starch in a leaf?
The iodine solution turns from browny-orange to blue-black.
59
What are lipids and their functions in plants?
Lipids are fats and oils that:
* Make plant cuticles waterproof
* Serve as energy stores
* Make cell membranes
60
What do plants need to synthesize all amino acids?
Nitrates absorbed from the soil
61
What is the role of proteins in plants?
Proteins act as enzymes for photosynthesis and respiration, and are essential for growth.
62
What are the main parts of a seed?
The main parts of a seed are:
* Embryo
* Food store
* Seed coat
63
What occurs during germination?
Water enters the seed, activates enzymes, breaks down starch into glucose, and oxygen allows the embryo to respire.
64
What is a key fact about the castor oil plant?
Just five seeds can contain enough ricin to kill a human.
65
What is yield in the context of farming?
Yield is the highest possible amount of useful product obtained from crops and land.
66
What is the purpose of fertilizers in agriculture?
Fertilizers provide essential mineral salts for healthy plant growth.
67
List three key mineral salts found in fertilizers and their functions.
* Nitrates: For healthy leaves
* Phosphates: For healthy roots
* Potassium: For healthy stems and leaves
68
What are pesticides used for?
Pesticides kill organisms that can damage crops.
69
What is the impact of using the same crop variety over large areas?
It creates a monoculture, increasing the risk of disease spread and reducing biodiversity.
70
What environmental problem can arise from excessive fertilizer use?
Eutrophication
71
What happens during eutrophication?
High nutrient levels lead to algal blooms, which block sunlight and deplete oxygen in water.
72
What is the consequence of using neonicotinoid insecticides?
They can harm pollinator populations, such as bees.
73
Fill in the blank: Plants need _______ from the soil to make proteins.
nitrates
74
What is potato blight?
A specific disease that affects potatoes
## Footnote
Potato blight is caused by the fungus-like organism Phytophthora infestans.
75
What happens when a farmer repeatedly plants wheat in the same field?
Lower yields due to nutrient depletion and pest build-up
## Footnote
This practice can lead to reduced soil fertility and increased vulnerability to diseases.
76
Why were neonicotinoid insecticides banned for use on oilseed rape and wheat?
They were found to be harmful to bees and other pollinating insects
## Footnote
Concerns about their impact on pollination and ecosystem health prompted the ban.
77
What is the effect of a selective insecticide on wheat aphids?
It kills the wheat aphids without harming the wheat plants.
78
What is the effect of a general insecticide on wheat aphids?
It kills the wheat aphids but can also harm other insects present.
79
What does a selective herbicide do in a wheat field?
It kills broad-leaved weeds without affecting wheat plants or aphids.
80
List the components of a basic food web for a wheat field.
* Wheat (producer) → Aphids (primary consumer) → Ladybirds (secondary consumer)
* Wheat (producer) → Grasshoppers (primary consumer) → Birds (secondary/tertiary consumer)
* Wheat (producer) → Mice (primary consumer) → Owls (secondary/tertiary consumer)
81
What is crop rotation?
Planting different crops in a sequence on the same land
## Footnote
This method helps maintain soil fertility and reduce pest build-up.
82
How can farmers reduce the use of synthetic pesticides and fertilizers?
By employing integrated pest management and using natural pest control methods.
83
Why do farmers remove hedgerows?
To create larger fields for efficient use of machinery
## Footnote
Larger fields can potentially increase crop yield.
84
Name two essential mineral salts found in fertilizers.
* Nitrates
* Phosphates
85
What is the role of nitrates in plant growth?
Necessary for the production of healthy leaves and overall plant growth.
86
What is the function of phosphates in plants?
Promote the development of healthy roots.
87
How do selective herbicides benefit wheat farmers?
They kill specific weeds without harming the wheat crop.
88
What is one potential environmental consequence of overusing fertilizers?
Eutrophication, leading to harmful algal blooms.
89
Why is monoculture problematic for farmers?
Reduces biodiversity and increases vulnerability to disease.
90
What is cross-breeding in plants?
Breeding two different varieties together to produce offspring with beneficial traits.
91
What are the negative impacts of persistent insecticides?
They can bioaccumulate and harm non-target organisms.
92
List two reasons for growing new crop varieties.
* Higher yields
* Greater resistance to diseases
93
What can excessive use of fertilizers do to aquatic ecosystems?
Lead to eutrophication and the death of aquatic life.
94
What is the carbon cycle?
The movement of carbon through different parts of the Earth's system.
95
What do plants take in during photosynthesis?
Carbon dioxide and water.
96
What are the products of photosynthesis?
Glucose and oxygen.
97
Why is light considered a limiting factor for photosynthesis?
Low light intensity limits the rate of photosynthesis.
98
What happens to glucose produced during photosynthesis?
* Used for energy
* Converted to starch for storage
* Transported as sugars
99
What are the reactants of aerobic respiration in plants?
Glucose and oxygen.
100
What is the main function of root hairs?
Increase surface area for efficient water and nutrient absorption.
101
How do xylem vessels function in plants?
They transport water and dissolved minerals from roots to other plant parts.
102
What is the main function of seeds in plants?
Reproduction and dispersal of new plants.
103
How is starch formed and stored in plants?
Converted from glucose and stored in various parts like chloroplasts and tubers.
104
What is the impact of a lack of nitrates in soil on plants?
Stunted growth and yellowing leaves due to insufficient protein production.
105
What is organic farming?
A farming method that primarily uses natural fertilizers and avoids synthetic pesticides.
106
What is the role of hoverfly larvae in organic farming?
They are used as biological control to manage aphid populations.
107
How do organic farming methods affect biodiversity?
They tend to increase biodiversity compared to conventional farming.
108
What is a potential drawback of organic farming?
Organic foods can be more expensive due to the need for more space.
109
What is the significance of magnesium in plants?
Essential for chlorophyll production.
110
Why is more research needed on organic farming?
To fully understand its benefits and implications for agriculture.
