Bio-120 Lecture Exam Unit 3

What is the Kingdom Plantae?

Multicellular, eukaryotic, autotrophic, and sessile organisms that perform photosynthesis.

What are plant cells like?

They are eukaryotic, meaning they have a nucleus and organelles.

What is the role of chloroplasts in plants?

Chloroplasts help plants make food through photosynthesis using sunlight, water, and CO₂.

What is the cuticle in plants?

A waxy layer on leaves and stems that prevents water loss.

What do stomata do?

They allow gases (CO₂ in, O₂ out) to move in and out of the plant.

What does the cell wall do?

It gives structure and protection to plant cells.

What are nonvascular plants?

Plants without vascular tissue (xylem and phloem); they are small and must stay close to the ground.

How do vascular plants differ?

Vascular plants have xylem and phloem for water and nutrient transport, allowing them to grow larger.

Examples of nonvascular plants?

Mosses and liverworts.

Examples of vascular plants?

Ferns, pine trees, and flowering plants.

What are vascular plant features?

They have roots, stems, leaves, and vascular tissue (xylem and phloem).

How do vascular plants reproduce?

By spores (in ferns) or seeds (in gymnosperms and angiosperms).

What happens in the gametophyte stage?

It produces gametes (sperm and eggs).

What is the sporophyte stage?

The dominant stage in most plants where spores are produced.

What are gymnosperms?

Cone-bearing plants like pine trees that produce seeds in cones.

What are angiosperms?

Flowering plants that produce seeds enclosed in fruits.

What are monocots?

Plants with one seed leaf, parallel leaf veins, and fibrous roots (e.g., grass, corn).

What are dicots?

Plants with two seed leaves, net-like leaf veins, and taproots (e.g., roses, beans).

What are the parts of a seed?

Seed coat (protective layer), embryo (baby plant), and cotyledons (nutrient storage).

What is the seed coat?

It protects the seed from damage and water loss.

What is the embryo in a seed?

The developing plant, including the root (radicle) and shoot (plumule).

What is the male part of a flower?

The stamen, which includes the anther (produces pollen) and filament (supports the anther).

What is the female part of a flower?

The carpel/pistil, which includes the stigma (catches pollen), style (connects to the ovary), and ovary (contains eggs).

What is fertilization in plants?

When pollen meets the ovule, forming a seed (with a diploid embryo).

What is pollination?

The transfer of pollen from the male to the female part of a flower.

What are the agents of pollination?

Wind, insects, animals, and water.

How are seeds dispersed?

By wind, water, animals, or mechanical methods (e.g., exploding seed pods).

What are nonvascular plants?

Nonvascular plants lack vascular tissue and must live in moist environments for reproduction.

What is a bryophyte?

A bryophyte is a nonvascular plant like mosses, liverworts, and hornworts.

Examples of true mosses (Bryophyta)?

Mnium, Sphagnum, Polytrichum.

What are the key traits of bryophytes?

No roots, stems, or leaves; gametophyte is the dominant generation; water is needed for reproduction.

How do mosses reproduce?

Mosses reproduce using water-dependent sperm and spores that grow from the gametophyte.

What are liverworts (Hepaticophyta)?

Liverworts have flat, leaf-like structures called thalli and reproduce both sexually and asexually.

Examples of liverworts?

Marchantia, Hepatica, Jamesoniella.

What is unique about hornworts (Anthocerophyta)?

Hornworts have a thalloid body and a horn-like sporophyte that grows directly from the gametophyte.

Example of hornworts?

Anthoceros.

What is the life cycle of bryophytes?

Bryophytes have alternation of generations with a gametophyte (n) and sporophyte (2n) stage.

What do antheridia and archegonia do?

Antheridia produce sperm, and archegonia produce eggs in bryophytes.

How do bryophytes reproduce?

Water is essential for sperm to reach the egg, leading to fertilization and spore production.

What are ferns (Pteridophyta)?

Ferns are vascular plants with true roots, stems, and leaves.

What are the key characteristics of ferns?

Ferns have vascular tissue (xylem and phloem) and the sporophyte is the dominant stage.

What are sori in ferns?

Sori are clusters of sporangia on the underside of fern fronds where spores are produced.

What is sporangia in ferns?

Sporangia are structures that produce spores in ferns.

What is annulus in ferns?

Annulus is a ring of cells that helps eject spores from the sporangia.

How do ferns reproduce?

Ferns reproduce by spores, not seeds.

What is the gametophyte stage in ferns?

The gametophyte stage is a small, heart-shaped structure called a prothallus that is photosynthetic.

What does the gametophyte contain?

The gametophyte contains antheridia (male) and archegonia (female).

What happens during fertilization in ferns?

Fertilization leads to the formation of a new sporophyte.

Examples of ferns?

Maidenhair Fern, Bracken Fern.

What are fern allies?

Fern allies are plants closely related to ferns but with unique features.

What are horsetail ferns (Equisetales)?

Horsetail ferns have jointed stems and reproduce by spores.

What are whisk ferns (Psilotales)?

Whisk ferns have simple structures, no true leaves or roots, and reproduce by spores.

What are club mosses and spike mosses (Lycopodiophyta)?

Club mosses and spike mosses are small plants with scale-like leaves and vascular tissue.

Examples of club mosses and spike mosses?

Selaginella, Lycopodium, Isoetes (Quillworts).

What are strobili in club mosses?

Strobili are cone-like structures that bear sporangia and help disperse spores.

What is the significance of lycophyte reproduction?

Lycophyte reproduction marks a transition toward seed plants and set the stage for the evolution of seed-producing plants like gymnosperms and angiosperms.

What is the evolutionary importance of Lycophytes?

Lycophytes helped evolve the structures needed for seed production, leading to the development of groups like Gnetophyta, Cycadophyta, Pinophyta, Ginkgophyta, and Anthophyta (flowering plants).What is a gymnosperm?

Do gymnosperms have flowers?

No, gymnosperms do not have flowers; they reproduce using cones.

What is the dominant generation in gymnosperms?

The dominant generation in gymnosperms is the sporophyte generation.

What is Cycadophyta (Cycads)?

Cycads are gymnosperms that are dioecious (separate male and female plants) and have large cones for reproduction.

What is a common example of a cycad?

Sago "Palm" is a common example, though it is not a true palm.

What do male cones in cycads do?

Male cones produce pollen and are elongated in shape.

What do female cones in cycads do?

Female cones are larger, rounder, and contain ovules for fertilization.

How does fertilization occur in cycads?

Fertilization occurs via motile sperm (sperm can move).

What is Ginkgophyta (Ginkgo Trees)?

Ginkgophyta includes the only living species, Ginkgo biloba, also known as the maidenhair tree.

What is unique about ginkgo trees?

Ginkgo trees are dioecious (separate male and female trees) and female trees produce fleshy seeds with a strong odor.

What is special about the seeds of ginkgo trees?

The seeds are not fruits (they develop from an ovule, not an ovary), and fertilized seeds have a strong odor.

Why are ginkgo trees planted in cities?

They are resistant to pollution, making them a popular urban tree.

What is Pinophyta (Conifers)?

Pinophyta is the largest gymnosperm group, including trees like pine, spruce, fir, cypress, and juniper.

What is the role of male cones in conifers?

Male cones produce pollen grains (male gametophytes) to be carried by wind.

What is the role of female cones in conifers?

Female cones are larger, house ovules, and eventually produce seeds after fertilization.

How do conifers reproduce?

Conifers reproduce via wind pollination.

What are examples of Pinophyta?

Pine, spruce, fir, cypress, juniper are all examples of conifers.

What is unique about the yew tree?

The yew tree produces a fleshy aril (fruit-like structure) but is not a true fruit. It also produces Taxol, used in chemotherapy.

What is unique about junipers?

Junipers have fleshy seed cones that are often called "berries," but they are not true berries.

What is Gnetophyta?

Gnetophyta is a diverse group of gymnosperms with three distinct genera: Gnetum, Welwitschia, and Ephedra.

What is Gnetum?

Gnetum is mostly tropical, with broad leaves and characteristics similar to angiosperms.

What are the key reproductive structures in gymnosperms?

Male cones, female cones, pollen grains, ovules, and seeds.

What is a seed in gymnosperms?

A seed contains the embryo and food supply and develops on the scale of a cone.

What are sepals in a flower?

Sepals are leaf-like structures that protect the flower while it’s still a bud.

What are petals in a flower?

Petals are colorful parts of the flower that attract pollinators like bees and butterflies.

What is the receptacle in a flower?

The base of the flower that holds all parts together.

What is the pedicel in a flower?

The stalk that holds the flower up.

What does the stigma do?

The stigma is the sticky tip where pollen lands.

What does the ovary do?

The ovary contains ovules, which become seeds after fertilization.

What is the process of fertilization in flowers?

Pollen moves from the anther to the stigma, then down the style to the ovary, where it fertilizes the ovule, turning it into a seed.

What is the calyx?

The calyx is the group of sepals together.

What is the corolla?

The corolla is the group of petals together.

What are the three ways the ovary can be positioned in a flower?

Hypogynous (above petals and sepals), epigynous (below petals and sepals), and perigynous (level with other parts).

What are composite flowers?

Composite flowers, like sunflowers, are made of many tiny flowers, including ray flowers (look like petals) and disk flowers (center, where seeds form).

What happens during fertilization in plants?

Once pollen reaches the egg in the ovary, fertilization occurs, and a seed begins to grow.

What is a fruit?

A fruit is a ripened ovary, and the fertilized ovule inside it becomes a seed.

What is the pericarp in fruits?

The pericarp is the wall of the ovary, which becomes the fruit and consists of the exocarp (outer skin), mesocarp (middle layer), and endocarp (inner layer, may be hard like a pit or soft).

What are dry fruits?

Dry fruits are fruits that don’t have a fleshy texture, and can be indehiscent (don’t split open) or dehiscent (split open to release seeds).

What are indehiscent dry fruits?

Indehiscent fruits don’t split open; examples include achene (sunflower), caryopsis (corn), nut (hazelnut), and samara (maple).

What are dehiscent dry fruits?

Dehiscent fruits split open to release seeds; examples include follicle (milkweed), legume (beans), silique, and capsule (poppy).

What is a drupe?

A drupe is a fleshy fruit with one seed and a hard pit (peach, cherry).

What is a berry?

A berry is a fleshy fruit with multiple seeds (tomato, grape).

What is a pepo?

A pepo is a berry with a tough skin (melon, cucumber).

What is a pome?

A pome is a fleshy fruit from fused floral parts (apple, pear).