Question 1

A potato is a type of ________ known as a ________.
A) modified root; pneumatophore
B) root; lateral root
C) modified stem; stolon
D) modified stem; tuber

Accepted Answer

A potato is a modified stem known as a tuber. It is a swollen, underground stem that stores nutrients like starch, rather than a root or a modified root like a pneumatophore. It also differs from a lateral root or a stolon, which are both types of roots.

Question 2

How would you expect the root system of a plant grown by hydroponics to compare to the root system of a plant grown in poor soil? The root system of a plant grown by hydroponics would be ________.
A) more developed
B) less developed
C) about the same
D) absent

Accepted Answer

Hydroponics provides plants with easily accessible nutrients and water, reducing the need for extensive root development compared to plants in poor soil, which must develop larger root systems to search for nutrients and water.

Question 3

Pines have needlelike leaves, with the adaptive advantage of ________.
A) increased surface area, increasing photosynthesis
B) increased surface area, increasing gas exchange
C) decreased surface area, reducing gas exchange
D) decreased surface area, reducing water loss

Accepted Answer

Pines have adapted to reduce water loss in dry environments by reducing their surface area through the evolution of needlelike leaves. This reduces the amount of water lost through transpiration while still allowing for photosynthesis.

Question 4

You find a plant unfamiliar to you and observe that it has vascular bundles scattered throughout the stem cross section. What do you conclude about the plant?
A) It is probably an herbaceous eudicot.
B) It will probably get annual rings of wood.
C) It is probably a monocot.
D) It could be either a young eudicot or a monocot.

Accepted Answer

Monocots typically have vascular bundles scattered throughout the stem cross section, unlike eudicots which usually have them arranged in a ring. This characteristic is a key feature distinguishing monocots from eudicots.

Question 5

Strolling in the Sonoran Desert, you come upon a stately Saguaro cactus. The large central "trunks" of this cactus are covered with numerous smaller spines. The central stalks are modified ________ used for water storage and spines are modified ________ used for protection.
A) stems; leaves
B) leaves; leaves
C) petioles; leaf blades
D) leaf blades; trichomes
E) stems; fruits

Accepted Answer

The central stalks of the Saguaro cactus are modified stems used for water storage, and the numerous smaller spines are modified leaves used for protection.

Question 6

Which part of a plant absorbs most of the water and minerals taken up from the soil?
A) root cap
B) root hairs
C) the thick parts of the roots near the base of the stem
D) storage roots
E) sections of the root that have secondary xylem

Accepted Answer

The root hairs are responsible for most of the water and mineral uptake in plants as they increase the surface area of the roots and greatly enhance their ability to absorb nutrients from the soil.

Question 7

While walking a cornfield, you notice roots emerging from the corn stalks themselves, and you suspect that these roots are helping to hold the plants upright. These roots belong to a category of roots known as ________.
A) taproots
B) fibrous roots
C) adventitious roots
D) root hairs
E) special roots

Accepted Answer

Adventitious roots are roots that arise from an unexpected source, such as from a stem or leaf. In the case of corn, adventitious roots emerge from the lower stem of the plant and help to anchor the plant in the soil, providing additional support to keep the plant upright. This is especially important in windy conditions, where the plants may be at risk of being blown over. Taproots and fibrous roots are types of primary root systems typically found in different types of plants, whereas root hairs are small extensions of roots that increase surface area for absorption of water and nutrients. "Special roots" is not a recognized category of roots.

Question 8

What is a disadvantage of having small, needlelike leaves?
A) increased transpiration rate
B) decreased transpiration rate
C) increased efficiency of light capture
D) decreased efficiency of light capture

Accepted Answer

Small, needlelike leaves have a reduced surface area, which can decrease the efficiency of light capture compared to broader leaves.

Question 9

Loss of water from the aerial parts of plants is called ________.
A) hydration
B) high heat of vaporization
C) respiration
D) gas exchange
E) transpiration

Accepted Answer

Transpiration is the loss of water from the aerial parts of plants, mostly through stomata on leaves. Hydration refers to the uptake of water by plant cells. High heat of vaporization refers to the high amount of heat required to turn water from liquid to gas. Respiration is the process by which organisms convert nutrients into usable energy. Gas exchange refers to the exchange of gases (such as oxygen and carbon dioxide) between an organism and its environment.

Question 10

Carbon dioxide enters the inner spaces of the leaf through the ________.
A) cuticle
B) epidermal trichomes
C) stoma
D) phloem
E) walls of guard cells

Accepted Answer

Carbon dioxide enters the inner spaces of the leaf through the stomata, which are specialized pores on the surface of the leaf.

Question 11

The surface area of a plant's root system is substantially larger than the surface area of its shoot system. The extensive surface area of roots is an adaptation associated with ________.
A) contact with soil particles for mineral and water absorption
B) the internal structure of the vascular tissue in roots
C) the storage of nutrients within the root system
D) the release of carbon dioxide generated by photosynthesis
E) the fact that roots absorb materials while shoots do not

Accepted Answer

The extensive surface area of roots allows for more contact with soil particles, which enhances the plant's ability to absorb minerals and water from the soil. This adaptation is crucial for plant growth and survival.

Question 12

A student examining leaf cross sections under a microscope finds many loosely packed cells with relatively thin cell walls. The cells have numerous chloroplasts. What type of cells are they?
A) parenchyma
B) xylem
C) endodermis
D) collenchyma
E) sclerenchyma

Accepted Answer

Parenchyma cells are loosely packed with thin cell walls and contain chloroplasts. Xylem cells have thick walls and do not contain chloroplasts. Endodermis cells have a specialized function in regulating water and nutrient uptake, but do not typically contain chloroplasts. Collenchyma cells have thicker walls than parenchyma cells and provide support for young stems and leaves. Sclerenchyma cells have thick secondary cell walls and provide structural support to mature tissue.

Question 13

Trichomes ________.
A) absorb sunlight, increasing the temperature of leaves
B) open and close for gas exchange
C) repel or trap insects
D) increase water loss from leaves

Accepted Answer

Trichomes are small hair-like structures found on the surface of leaves, stems, and other plant parts, which can secrete substances that repel or trap insects. They can also be used for defense mechanisms against herbivores.

Question 14

Some botanists argue that the entire plant should be considered as a single unit rather than a composite of many individual cells. Which of the following cellular structures best supports this view?
A) cell wall
B) cell membrane
C) cytosol
D) vacuole
E) plasmodesmata

Accepted Answer

Plasmodesmata are channels between plant cells that allow for communication and transport of molecules between cells. These channels connect the cytoplasm of adjacent cells, creating a network of interconnected cells that function as a single unit. This supports the view that the entire plant should be considered as a single unit, rather than a composite of individual cells.

Question 15

One important difference between the anatomy of roots and the anatomy of leaves is that ________.
A) only leaves have phloem and only roots have xylem
B) root cells have cell walls and leaf cells do not
C) a waxy cuticle covers leaves but is absent from roots
D) vascular tissue is found in roots but is absent from leaves
E) leaves have epidermal tissue but roots do not

Accepted Answer

Leaves have a waxy cuticle that prevents water loss and protects them from environmental stresses, whereas roots do not have a cuticle as they need to absorb water and nutrients from soil. This is an important difference in the anatomy of roots and leaves. The other options provided do not accurately reflect the differences between root and leaf anatomy.

Question 16

Compared to most animals, the growth of most plant structure is best described as ________.
A) perennial
B) weedy
C) indeterminate
D) derivative
E) primary

Accepted Answer

Plant growth is typically indeterminate, meaning it continues throughout the lifespan of the plant, unlike animals, whose growth is mostly determinate, meaning it stops at a certain point in their lifespan.

Question 17

Axillary buds ________.
A) are produced by the cork cambium
B) have dormant meristematic cells
C) are composed of a series of internodes lacking nodes
D) give rise to secondary xylem
E) do not form a vascular connection with the primary shoot

Accepted Answer

Axillary buds contain dormant meristematic cells that can give rise to new shoots under appropriate conditions.

Question 18

Plants that have leaves arranged in a rosette
A) have a circular arrangement of leaves and long internodes.
B) lack stems.
C) have greatly shortened internodes.
D) always have compound leaves.

Accepted Answer

Plants that have leaves arranged in a rosette have greatly shortened internodes, meaning that the stem is very short, if there is one at all. The leaves are arranged in a circular pattern at the base of the plant, but this does not necessarily mean that they are circular in shape or compound.

Question 19

Which type of modified stems grow horizontally belowground and produce new plants at nodes?
A) blades
B) tubers
C) stolons
D) thorns
E) rhizomes

Accepted Answer

Rhizomes are modified stems that grow horizontally underground and have nodes that can produce new plants. Blades are flat leaves, tubers are thickened underground stems, stolons are stems that grow horizontally above ground, and thorns are modified branches or leaves.

Question 20

When comparing root systems of corn plants growing on a square foot in a fertilized and irrigated cornfield with the root systems of natural prairie plants growing in a meadow, what result do you expect to see?
A) The overall mass of roots will be identical in a cornfield and on a meadow.
B) The mass and length of roots in a cornfield will be higher because soil is fertilized.
C) The mass and length of roots on a meadow will be higher because soil is poorer and there is a higher diversity of plants.
D) The overall mass of roots on a meadow will be lower but the length will be higher since roots need to grow deeper to reach nutrients.

Accepted Answer

In a natural meadow, the soil is typically poorer and there is a higher diversity of plants. This leads to a higher competition for resources between the different plant species, which results in longer and more widespread root systems. In a fertilized and irrigated cornfield, the soil is enriched with nutrients and the crop is the only plant species, leading to shorter and less spread-out root systems. Therefore, the mass and length of roots on a meadow will be higher than in a cornfield.

Quiz 34: Plant Form and Function

A potato is a type of known as a .

How would you expect the root system of a plant grown by hydroponics to compare to the root system of a plant grown in poor soil? The root system of a plant grown by hydroponics would be ________.

Pines have needlelike leaves, with the adaptive advantage of ________.

You find a plant unfamiliar to you and observe that it has vascular bundles scattered throughout the stem cross section. What do you conclude about the plant?

Strolling in the Sonoran Desert, you come upon a stately Saguaro cactus. The large central "trunks" of this cactus are covered with numerous smaller spines. The central stalks are modified used for water storage and spines are modified used for protection.

Which part of a plant absorbs most of the water and minerals taken up from the soil?

While walking a cornfield, you notice roots emerging from the corn stalks themselves, and you suspect that these roots are helping to hold the plants upright. These roots belong to a category of roots known as ________.

What is a disadvantage of having small, needlelike leaves?

Loss of water from the aerial parts of plants is called ________.

Carbon dioxide enters the inner spaces of the leaf through the ________.

The surface area of a plant's root system is substantially larger than the surface area of its shoot system. The extensive surface area of roots is an adaptation associated with ________.

A student examining leaf cross sections under a microscope finds many loosely packed cells with relatively thin cell walls. The cells have numerous chloroplasts. What type of cells are they?

Trichomes ________.

Some botanists argue that the entire plant should be considered as a single unit rather than a composite of many individual cells. Which of the following cellular structures best supports this view?

One important difference between the anatomy of roots and the anatomy of leaves is that ________.

Compared to most animals, the growth of most plant structure is best described as ________.

Axillary buds ________.

Plants that have leaves arranged in a rosette

Which type of modified stems grow horizontally belowground and produce new plants at nodes?

When comparing root systems of corn plants growing on a square foot in a fertilized and irrigated cornfield with the root systems of natural prairie plants growing in a meadow, what result do you expect to see?