Plant Tissue Quiz

Questions and Answers

What is the primary function of parenchyma cells in plants?

Storage, photosynthesis, and metabolic functions (correct)

Regulating water loss

Transportation of nutrients

Providing structural support

Which vascular tissue is responsible for the transport of water and minerals from the roots to the rest of the plant?

Xylem (correct)

Pith

Cortex

Phloem

In stem structures, what is the name given to the central vascular cylinder present in angiosperm roots?

Cortex

Stele (correct)

Pericyle

Pith

What characteristic distinguishes collenchyma cells from parenchyma cells?

Collenchyma have thicker and uneven cell walls Signup and view all the answers

What is the role of vascular cambium in the growth of a woody stem?

Enables secondary growth by forming new vascular tissues Signup and view all the answers

Which of the following tissues would be absent in a root that often lacks secondary growth?

Vascular cambium Signup and view all the answers

Which cell type is known for providing rigid support in plants?

Sclerenchyma Signup and view all the answers

What differentiates the epiderma from the periderm in woody stems?

Periderm protects against water loss and pathogens Signup and view all the answers

What distinguishes a taproot system from a fibrous root system?

Taproot systems include a main vertical root and lateral roots branching off. Signup and view all the answers

Which statement correctly describes apical and axillary buds?

Apical buds suppress the growth of axillary buds through apical dominance. Signup and view all the answers

In terms of leaf morphology, how do monocots and eudicots primarily differ?

Eudicots are characterized by branching veins, while monocots are known for parallel veins. Signup and view all the answers

What role do nodes and internodes play in the structure of stems?

Internodes connect nodes and provide structural integrity to the stem. Signup and view all the answers

What is the main function of the cuticle in dermal tissue?

To prevent water loss from the epidermis of nonwoody plants. Signup and view all the answers

Which of the following modified stems is primarily underground?

Rhizomes. Signup and view all the answers

Which type of vascular tissue arrangement is typical for monocots?

Scattered vascular bundles. Signup and view all the answers

How do trichomes benefit plants?

They can help with insect defense. Signup and view all the answers

What role do guard cells play in leaf anatomy?

They regulate the opening and closing of stomatal pores. Signup and view all the answers

Which statement accurately describes the mesophyll in eudicot leaves?

It is composed of two distinct layers: palisade and spongy mesophyll. Signup and view all the answers

What is the primary function of vascular tissue in leaves?

To transport water and nutrients throughout the plant. Signup and view all the answers

Which of the following statements regarding secondary growth is false?

It is common in leaves of gymnosperms. Signup and view all the answers

What distinguishes early wood from late wood in trees?

Early wood has thin cell walls to optimize water delivery. Signup and view all the answers

Which of the following structures is NOT associated with the vascular cambium?

It generates cork tissue for outer bark. Signup and view all the answers

What structural feature is characteristic of veins in leaves?

They are surrounded by a protective bundle sheath. Signup and view all the answers

In terms of growth patterns, which plant group exhibits secondary growth?

Secondary growth is common in gymnosperms and many eudicots. Signup and view all the answers

Which statement correctly describes the role of the basal cell in seed development?

It produces a multicellular suspensor anchoring the embryo. Signup and view all the answers

What is the function of the hypcotyl in a seedling?

To connect the cotyledons and the radicle. Signup and view all the answers

Which embryonic structure emerges first during the germination process?

The radicle. Signup and view all the answers

Which function is NOT associated with the fruit derived from the ovary?

It aids in water absorption for the seeds. Signup and view all the answers

Among eudicots, what is a characteristic feature of seeds such as castor beans?

They have thin cotyledons. Signup and view all the answers

How does the coleoptile function in grass seeds during germination?

It covers the young root as it pushes through the soil. Signup and view all the answers

What initiates the process of germination in seeds?

The uptake of water through imbibition. Signup and view all the answers

What characterizes the cotyledons in monocots such as maize?

They are referred to as scutellum. Signup and view all the answers

What is the main purpose of endosperm development in most monocots?

To store nutrients for the seedling Signup and view all the answers

In the process of double fertilization, what happens to the second sperm cell?

It combines with the polar nuclei to form the endosperm. Signup and view all the answers

Which mechanism does not typically facilitate pollination in angiosperms?

Soil-based pollen movement Signup and view all the answers

What characterizes the development of the female gametophyte in an ovule?

One megaspore survives to become the embryo sac Signup and view all the answers

Which statement accurately describes coevolution in flowering plants and their pollinators?

Both flowering plants and pollinators evolve in response to each other’s changes. Signup and view all the answers

What key feature distinguishes wind-pollinated species from those pollinated by animals?

They generate high volumes of pollen for effective dispersal. Signup and view all the answers

During the formation of a pollen grain, which component directly contributes to the male gametophyte?

The spore wall Signup and view all the answers

What role do the eight nuclei in the developing megaspore serve?

They are precursors to the embryo and endosperm. Signup and view all the answers

What is a distinguishing feature of complete flowers compared to incomplete flowers?

Complete flowers contain all four floral organs. Signup and view all the answers

Which statement accurately describes the process of double fertilization in angiosperms?

One sperm fertilizes the egg cell, and the other joins with two polar nuclei. Signup and view all the answers

What role do pollinators play in angiosperm reproduction?

They help in transferring pollen from one flower to another. Signup and view all the answers

Which statement best describes the male gametophyte development in angiosperms?

Pollen grains are formed from microspores through mitosis and cellular differentiation. Signup and view all the answers

How do dicot and monocot seeds differ in structure?

Dicot seeds have vascular bundles arranged in a ring while monocot seeds do not. Signup and view all the answers

What are the three types of fruit classification in angiosperms?

Simple, aggregate, and multiple fruits. Signup and view all the answers

Which feature characterizes aggregate fruits?

They consist of numerous smaller fruits from a single flower. Signup and view all the answers

What is the primary function of a flower's receptacle?

To support the floral organs. Signup and view all the answers

Study Notes

Vascular Tissues

Vascular tissues are comprised of two types: xylem and phloem.
The combined vascular tissue in stems and roots is known as the stele.
In angiosperms, the stele of roots forms a solid central vascular cylinder.
Vascular bundles, consisting of xylem and phloem, are found in the stele of stems and leaves.

Ground Tissue

Ground tissue is classified as tissues that are neither dermal nor vascular.
Pith refers to the ground tissue located inside the vascular tissue, while cortex is the ground tissue outside the vascular tissue.
The ground tissue system includes cell types specialized for storage, photosynthesis, and support.

Cell Types

Parenchyma Cells

Characterized by thin, flexible primary walls and lack of secondary walls.
They are the least specialized cells and perform various metabolic functions.
Retain the ability to divide and differentiate.

Collenchyma Cells

Grouped in strands, collencchyma cells support young plant shoots.
They possess thicker, uneven cell walls but lack secondary walls, allowing for flexible support.

Sclerenchyma Cells

These cells have thick secondary walls bolstered by lignin, making them rigid.
They are dead at functional maturity and include two types: sclereids and fibers.

Tissue Organization of Leaves

Leaves contain an epidermis with stomata for gas exchange (CO2 and O2).
Each stomatal pore is controlled by two guard cells that regulate its opening and closing.
Ground tissue, called mesophyll, is located between the upper and lower epidermis.
Eudicot mesophyll consists of palisade mesophyll (upper layer) and spongy mesophyll (lower layer) which facilitate gas exchange.
Vascular tissue in leaves is continuous with vascular tissue in stems, forming the leaf's veins, which serve as a skeleton.
Each vein has a protective sheath called a bundle sheath.

Secondary Growth

Occurs in woody plants' stems and roots, rarely in leaves.
Involves tissues produced by vascular cambium and cork cambium.
Typical of gymnosperms and many eudicots, but not found in monocots.

Vascular Cambium

A one-cell-thick cylinder of meristematic cells that develops from undifferentiated parenchyma.
Functions to increase the circumference and produce secondary xylem (wood) and secondary phloem.
Secondary xylem includes tracheids and vessel elements (only in angiosperms).
Early wood formed in spring has thinner walls; late wood formed in summer has thicker, supportive cells.
In temperate regions, vascular cambium becomes inactive during winter.

Root Systems

Most eudicots feature a taproot system: a main vertical root (taproot) and lateral roots branching from it.
Most monocots have a fibrous root system characterized by adventitious roots arising from stems or leaves and lateral roots coming from those.

Stems

Stems contain nodes (attachment points for leaves) and internodes (segments between nodes).
Axillary buds can form lateral shoots, while terminal buds at the shoot tip promote elongation.
Apical dominance inhibits axillary bud growth to maintain dormancy.
Many plants have modified stems, including rhizomes, bulbs, stolons, and tubers.

Leaves

Leaves primarily serve as photosynthetic organs, usually composed of a flattened blade and petiole that connects to the stem.
Monocots typically have parallel veins, whereas eudicots feature branching veins.
Leaf morphology can be used as a taxonomic criterion for angiosperm classification.

Tissue Types

Dermal Tissues

In nonwoody plants, the dermal system includes the epidermis, protected by a waxy cuticle to prevent water loss.
In woody plants, periderm replaces the epidermis in older stems and roots.
Trichomes are outgrowths from the shoot epidermis and can provide defense against pests.

Flower Structure and Function

Flowers are reproductive shoots of angiosperms, attached to the receptacle on the stem.
Comprise four floral organs: sepals, petals, stamens, and carpels; sepals and petals are sterile.
Stamens are made up of a filament and anther, where pollen is produced.
Carpels include a long style topped with a stigma for pollen reception, with an ovary housing ovules at the base.
Pistils are single or fused carpels; complete flowers contain all four organs while incomplete flowers lack one or more.
Clusters of flowers are termed inflorescences.

Male Gametophyte Development

Pollen develops from microspores in the microsporangia (pollen sacs) of anthers.
A microspore undergoes mitosis to produce a generative cell and a tube cell.
Pollen grains are composed of this two-celled male gametophyte and the spore wall.
Successful pollination leads to the formation of a pollen tube, which delivers sperm cells to the embryo sac.

Female Gametophyte Development

The embryo sac, or female gametophyte, develops within the ovule.
Each ovule contains two integuments surrounding the megasporangium.
One cell in the megasporangium undergoes meiosis to produce four megaspores; only one survives.
The surviving megaspore undergoes divisions to form a large cell with eight nuclei.

Pollination

Pollination in angiosperms is the transfer of pollen from an anther to a stigma.
Modes of pollination include wind, water, and animals.
Wind-pollinated species (like grasses and trees) release substantial amounts of pollen.

Flower-Pollinator Coevolution

Coevolution involves evolving interactions between species in response to each other.
Many flowering plants coevolve with specific pollinators, leading to particular flower shapes and sizes suited for certain pollinators.
Example: Darwin predicted a moth with a long tongue based on flower morphology.

Double Fertilization

Double fertilization occurs when two sperm cells discharge from a pollen tube into the embryo sac.
One sperm fertilizes the egg while the other fuses with polar nuclei, forming triploid endosperm for nourishment.

Seed Development, Form, and Function

Endosperm development usually occurs before embryo development, storing nutrients for seedlings or transferring them to cotyledons.
The first mitotic division of a zygote results in a basal cell and a terminal cell; the latter forms most of the embryo.
Seeds have a protective coat, enter dormancy, and typically consist of 5–15% water.
Eudicot embryos feature an embryonic axis and two cotyledons, while monocots have one cotyledon and specialized structures.

Seed Germination

Germination is initiated by imbibition, where seeds take up water.
The radicle (embryonic root) is the first to emerge, followed by the shoot tip breaking through.
In eudicots, a hook forms in the hypocotyl, pushing the cotyledons above ground.
In monocots, the coleoptile pushes through the soil.

Fruit Structure and Function

Fruits develop from the ovary and serve to protect seeds while facilitating dispersal by wind or animals.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on the functions and characteristics of different plant tissues, including parenchyma, collenchyma, and vascular tissues. Explore how these tissues contribute to plant growth and transport essential resources. This quiz will challenge your understanding of plant anatomy.