1
Q
What are the two types of growth in the stem?
A
- Primary
- Secondary
Primary growth occurs at the apical meristem, increasing stem length.
Secondary growth occurs at the lateral meristems, increasing the girth of the stem.
2
Q
What are the different layers of a leaf?
A
- Cuticle layer
- Upper epidermis
- Palisade layer
- Spongy layer
- Lower epidermis
- Stomata
3
Q
Describe the upper epidermis of a leaf.
A
Consists of a thin layer of cells that allow sunlight to pass through and initiate photosynthesis in underlying cells.
4
Q
What is the primary function of the palisade layer?
A
To conduct photosynthesis and convert carbon dioxide into cellular energy.
5
Q
Explain the function of the spongy layer in a leaf.
A
- To facilitate the diffusion of nutrients and gases through the stomata.
- Store products of photosynthesis.
- Contain vascular bundles for transporting nutrients throughout the plant.
6
Q
What do the palisade and spongy layers collectively form in a leaf?
A
Mesophyll
7
Q
What triggers stomata to open or close?
A
- Changes in light
- Hydration
- Temperature
8
Q
What function do roots serve for plants?
A
Storage of food and intake of water.
9
Q
What is the purpose of the root cap?
A
Protect other root tissues as the root grows into the soil.
The root cap also senses gravity and secretes a slimy substance to help roots move through the soil.
10
Q
What is the function of the cortex in roots?
A
food storage
11
Q
What are the roles of the epidermis and cortex in roots?
A
- Epidermis: Provides an outer layer of protection.
- Cortex: Stores products of photosynthesis.
12
Q
What is the main function of the root system?
A
It grows below ground, anchors the plant, and absorbs water and minerals needed for survival.
13
Q
What are the two types of root systems identified by researchers?
A
- Taproot systems
- Fibrous root systems
14
Q
What is the main characteristic of taproot systems?
A
They have a main root that grows vertically and secondary roots that develop as outgrowths.
15
Q
What is the main characteristic of fibrous root systems?
A
They are shallow in depth and consist of roots that are similar in size.
16
Q
What is the main function of the root meristem?
A
It produces columella cells that replace damaged cells of the root cap.
17
Q
What region of the root consists of apical meristem cells contributing to overall growth?
A
Meristematic region
18
Q
Which region of the root is responsible for increased length and growth of plant roots?
A
Region of elongation
19
Q
Where are the first root hairs located in the root system?
A
Region of maturation
20
Q
What grows horizontally from the pericycle and facilitates water and nutrient transport?
A
Lateral roots
21
Q
What is the innermost layer of the cortex of the mature root called?
A
Endodermis
Contains fatty substances in roots and blocks water movement between the cortex and inner layers
22
Q
What is the scientific study of plants called?
A
Botany
Botanists study the structures and functions of plants, their evolutionary relationships, and more.
23
Q
What is the term for pollination by the wind, insects, birds, bats, or water?
A
Cross-pollination
24
Q
What does the anther of a stamen produce?
A
Pollen, the male sex cell.
25
What are the four important elements **contributing to the health** of photosynthetic plants?
* Nutrients
* Sunlight
* Temperature
* Water
26
What is the **Diffusion Pressure Deficit** in plants?
| (DPD)
The difference between the osmotic and turgor pressure of a plant cell.
## Footnote
Turgor: The pressure put on the cell by the cytoplasm against the cell wall.
27
What happens when the calculated Diffusion Pressure Deficit (DPD) **is greater than zero** in plants?
**Plants are in need of water** and the roots will absorb water to reestablish turgor pressure within the plant cells.
28
What is **root pressure** in plants?
**Hydrostatic pressure** created in the roots that allows water to move up into the xylem.
29
How do roots **adapt** to water availability in a plant's environment?
By increasing root **density** and root **depth**.
30
What are the **three methods** through which water **travels** into the cortex of a root?
* Apoplastic pathway
* Symplastic pathway
* Transmembrane pathway
31
What is the **apoplastic pathway** of water movement in roots?
Water movement between the cells and **through the cell walls** of the cortex.
32
What is the **symplastic pathway** of water movement in roots?
Transport from the **cytoplasm of one cell to the cytoplasm of another cell** within the cortex.
33
What is the **transmembrane pathway** of water movement in roots?
Water travels **across the plasma membranes** of cells in the cortex.
34
Where does water **ultimately travel** to within the cortex of a root?
Endodermal cells
## Footnote
They comprise the inner layer of the cortex.
35
What specialized part of the root **contains the xylem and phloem**?
Stele
36
What are **plasmodesmata** in plant cells?
Pores **connecting** adjacent cells to one another.
37
What is the **process by which water is lost** through the stomata of leaves?
Transpiration
## Footnote
Transpiration helps conduct water to different plant parts and makes water available to leaves for carrying out photosynthesis. It also helps balance the amount of water in the plants and keeps them cool.
38
What determines **the amount of water** absorbed by a plant?
Diffusion Pressure Deficit
| (DPD)
39
How does xylem move water **against gravity**?
Through **capillary action**, utilizing the unique properties of water including surface tension.
40
What are the **three unique properties** of water that enable capillary action in xylem?
* Surface tension
* Water adhesion
* Cohesion
41
How does water **enter** the roots of a plant?
osmosis
42
What is the process that **moves water all the way up** through tall plants?
transpirational pull
43
What does **xylem transport**?
water and dissolved minerals
44
What does **phloem transport**?
sugar and nutrients
45
What happens to the **phloem and xylem** during **secondary growth**?
Exterior phloem gets squished and replaced; interior primary xylem **dies** and is **replaced by secondary xylem**.
## Footnote
The dead xylem becomes heartwood, while functional xylem is known as sapwood.
46
What is the most well-supported **theory** explaining how **nutrients in sap** are **transported** throughout the phloem of the plant?
Pressure-flow hypothesis
47
What causes the **movement of sugar** towards sinks in the pressure-flow hypothesis?
**Decrease in hydrostatic pressure** within sieve tube elements near the sinks, resulting in a pressure gradient that drives more nutrients in that direction.
48
What happens to the **nutrients in the sap of roots** when phloem nutrients reach them?
Consumed rapidly by cellular respiration since roots are underground and **cannot perform photosynthesis**.
49
What is the role of **sieve tube elements** in phloem transport?
**Specialize in moving sap** but lack nuclei and other organelles, with their metabolic functions carried out by surrounding companion cells.
50
How does the plant **regulate the hydrostatic pressure** within the phloem?
By **actively transporting nutrients** into sieve tube elements from photosynthetic parts, then from sieve tube elements into sinks.
## Footnote
Sinks are areas in the plant that require a higher level of glucose such as fruit, young or growing leaves, roots and growing stems.
51
What does the **sap** transported by the phloem **contain**?
**High concentrations of sugars** created during photosynthesis and other nutrients.
52
What is the **significance of transpiration** in plants?
* Suction pressure is created, aiding in water conduction from roots.
* Helps maintain water balance in plants.
* Assists in maintaining turgidity of plant cells.
* Causes a cooling effect in plants.
* Plays a crucial role in the cycling of water on Earth.
53
How do **guard cells** affect the opening and closing of stomata?
They **surround** stomata and **control** their opening and closing.
## Footnote
When turgid, stomata opens; when flaccid, stomata closes.
54
What is the **transpiration rate**?
The extent to which **water is released** from plant leaves **into the environment**.
55
What **factors** can affect the **rate of transpiration**?
* **Relative humidity**: decrease in relative humidity increases transpiration rate.
* **Light intensity**: higher light intensity increases transpiration rate.
* **Temperature**: increase in temperature leads to stomatal opening and transpiration.
* **Availability of water**: if sufficient water is available, stomata opens.
56
What are **stomata** in plants?
**Openings in between guard cells** that allow plants to exchange gases, such as carbon dioxide and water vapor, with their outside environment.
57
What are **guard cells**?
A **pair of curved plant cells**, usually found on the underside of the leaf, that can expand and shrink, regulating gas flow.
58
What is the **primary function** of **photosynthesis**?
Convert **light energy** from the sun into **chemical energy**.
59
What are the **reactants** needed for photosynthesis?
* water
* sunlight
* carbon dioxide
60
Why is photosynthesis **important** to plants?
It **allows plants to make complex molecules like glucose** from simple molecules for energy, growth, cell development, and as a source of food for germinating seeds.
61
Where does the process of photosynthesis take **place** in plants?
chloroplast
## Footnote
The light-dependent reaction occurs in the thylakoids and the light-independent reaction in the stroma.
62
What are the **products** of the light-dependent reaction in photosynthesis?
* ATP
* NADPH
* Oxygen
63
What is the **alternation of generations** in plants?
It describes the unique nature of plant life cycles where they **alternate between two different stages** of life in each generation.
64
What are the **two main stages** in the **alternation** of generations in plants?
* **Sporophyte** (diploid stage)
* **Gametophyte** (haploid stage)
65
Where is the **sporangium** located in ferns?
Millions of sporangia are located on the **underside of the leaves**.
66
What is the **function** of the **endosperm** in plants?
Develops after fertilization as a **source of energy and nutrition** for the growing embryo.
67
# Define:
spores
Reproductive units or cells that **germinate or develop into new individuals** without fusion with other reproductive cells.
68
What is the **purpose** of bacteria producing spores?
Mainly for **survival** as opposed to reproduction.
69
What is **sporogenesis**?
The process by which the diploid sporophyte generation **produces spores** in plants.
## Footnote
These spores are initially haploid and are formed through meiosis. Subsequently, the formed spores undergo mitosis to give rise to a haploid gametophyte generation responsible for producing gametes.
70
What is **vegetative propagation**?
The process of **making new plants from a part** of the parent plant.
71
What is **grafting** in vegetative propagation?
**Attaching a scion, bud, stem, or branch** from one plant to the stem and roots of a **different plant**.
## Footnote
Plants typically grown through grafting are apples, pears, and plums.
72
What is **layering** in vegetative propagation?
When a part of the plant, usually the stem, is **covered with soil to develop its own root system**.
## Footnote
Examples of plants that are reproduced through layering include forsythia, rhododendron, and climbing vines.
73
What is **stolon propagation**?
Propagation that occurs **above ground through stems that grow horizontally** and develop into individual plants.
## Footnote
Plants commonly produced through stolons are strawberries, spider plants and some grasses.
74
What is a **stolon**?
A **horizontally growing stem** above ground that can become individual offspring.
75
What is a **sucker**?
A **shoot that arises from the existing root structure** of an established plant.
## Footnote
Plants that commonly reproduce through suckering include lilacs, roses, fruit trees.
76
How can **suckers** be propagated?
By **separating them from the parent root system** once they have their own root system.
77
What are **tubers**?
Special thickened underground stem sections that grow horizontally below the surface of the soil.
## Footnote
Tubers like potatoes and yam grow underground.
78
What is **cutting** in the context of plant propagation?
A plant segment **separated from the parent plant** and placed in a growing medium to develop roots and grow into an individual offspring.
## Footnote
Plants commonly propagated using cuttings include softwood trees, various shrubs.
79
What is the **final stage** of germination?
The **division of cells within the seed**, leading to the growth of the **seedling**.
80
What does **tropism** refer to in plants?
The ability of an organism to respond to a stimulus by **turning from one direction to another**.
## Footnote
'Tropism' comes from the Greek word tropos which means turning.
81
What are the **two types** of tropism based on the movement response of an organism?
* **Positive tropism**: movement or growth response toward the stimulus.
* **Negative tropism**: movement or growth response away from the stimulus.
82
How are **fast movements** in plants regulated?
Usually driven by **quick changes in water transport** supported by mechanical instabilities in the structure of the plants.
83
What regulates the relatively **slower movements** in plants?
These are created by the differential growth of the live tissues.
84
What determines the **direction** of tropism in plants?
The direction of the **stimulus** influencing the plant.
85
What is **chemotaxis**?
The **movement in the direction of a chemical stimulus** in the environment by an organism or a living motile cell.
86
What is **chemokinesis**?
A response of a cell in terms of its behavior toward a soluble chemical, which results in a **random movement**.
87
What is **phototropism**?
The growth or movement of a cell or an organism or part of an organism **toward the light**.
88
What does **positive gravitropism** represent?
The **growth of roots** toward the ground.
89
What is **gravitropism**?
The growth response of a plant **towards the gravitational field**, with roots growing towards the ground and stems growing away from it.
| Also known as geotropism.
90
What is **thigmotropism**?
A type of tropism where an organism **responds to touch stimuli**.
## Footnote
Positive thigmotropism moving towards the stimulus and negative moving away.
91
What is **hydrotropism**?
A form of tropism where an organism shows growth or movement **in response to water or moisture**.
92
What is **heliotropism**?
A type of tropism where the response of the organism is directed **towards sunlight**.
93
What is **thermotropism**?
A type of tropism where a part of an organism shows movement response to **temperature changes**.
94
What is **electrotropism**?
A type of tropism exhibited by an organism as a **response to the electric field**, with different cell types showing electrotropism.
95
What are some plant defenses against herbivores?
* Physical defenses - trichomes and thorns.
* Chemical compounds - substances that make the plant distasteful to herbivores.
96
What is the **hypersensitive response** in plants?
A defense mechanism that causes cells and tissues around the infection site to die off to prevent the spread of a pathogen.
97
What is **systemic acquired resistance?**
Before the hypersensitive response cells die, they release methylsalicylic acid, which activates signaling pathways that force distant cells to produce molecules that protect the plant against pathogens.
98
Explain the **relationship** between the hypersensitive response and systemic acquired resistance.
The **hypersensitive** response causes cells to die off, releasing a signal that triggers distant cells to produce protective molecules in systemic acquired resistance.
99
What is the primary function of **ethylene** in plants?
* promotes aging in plants
* ripens fruit
* causes mature leaves and flowers to age, fade, and drop
## Footnote
Ethylene is a growth inhibitor.
100
What is the main responsibility of **abscisic acid** (ABA) in plants?
* Induces dormancy in different plant organs.
* Causes leaf drop.
* Promotes seed dormancy.
* Closes stomata during drought conditions.
| Growth inhibitor.
101
What is a **node** in plant anatomy?
A structure that **attaches the petiole to the stem**.
## Footnote
Nodes help promote the growth of leaves, secondary stems, and flowers.
102
What is the **role** of a petiole?
Links a leaf with its associated node.
## Footnote
Petioles can be short, long, or absent (sessile leaves).
103
Describe the **arrangement of xylem and phloem** in dicot plants.
Form concentric **tubes** or **rings**.
## Footnote
The xylem is the inner ring and phloem is the outer ring.
104
# Fill in the blank:
The \_\_\_\_\_\_\_ is the distance between two nodes on a plant stem.
internode
## Footnote
Internodes can be affected by seasonal changes.
105
Where are **meristems** primarily located in plants?
At the **tips** of roots, stems, and leaves.
## Footnote
Meristems are responsible for controlling plant growth.
106
What are the **three main types** of meristems?
* Apical meristems
* Lateral meristems
* Intercalary meristems
## Footnote
Each type has a specific role in plant growth.
107
What is the role of **apical meristems**?
They allow for the **lengthening of roots and stems**.
## Footnote
Apical meristems are crucial for primary growth.
NYSTCE Biology
flashcards
Decks in class (21)
# Cards
-
Cell Types & Organelles160
-
Membrane Transport & Homeostasis (Cell Level)102
-
Structure & Function of Biomolecules101
-
Enzyme Function & Catalysis68
-
Cell Division & Differentiation97
-
Plant Structure & Function107
-
Animal Structure & Function186
-
Homeostasis & Immune Response (Organism Level)60
-
Photosynthesis & Respiration100
-
Metabolism of Biomolecules39
-
Ecosystems: Energy Flow & Cycling of Matter125
-
Population Dynamics & Biodiversity173
-
Evolutionary Mechanisms72
-
Genetic Diversity & Variation36
-
Unity & Diversity of Life85
-
Biological Organization Across Kingdoms83
-
Molecular Basis of Heredity97
-
Mutations & Genetic Consequences75
-
Patterns of Inheritance135
-
Genetic Technology & Applications104
-
Pedagogy for Biology Teaching40
