BIO 214 : Seed plants Chap 26

anther

sac-like structure at the tip of the stamen in which pollen grains are produced

Anthophyta

Phylum to which angiosperms belong

Barcoding

Molecular biology technique in which one or more short gene sequences taken from a well characterized portion of the genome is used to identify a species

Basal angiosperms

A group of plants that probably branched off before the separation of monocots and eudicots

Calyx

Whorl of sepals

Carpel

Single unit of pistils

Conifer

Dominant phylum of gymnosperms with the greatest variety of trees

Corolla

Collection of petals

Cotyledon

Primitive leaf that develops in the zygote; monocots have one cotyledon, and dicots have two cotyledons

Crop

Cultivated plant

Cycads

Gymnosperm that grows in tropical climates and resembles a palm tree; member of the phylum Cycadophyta

Dicot

(Also eudicot) related group of angiosperms whose embryos possess two cotyledons

Dioecious

Describes a species in which the male and the female reproductive organs are carried on separate specimens

Filament

Thin stalk that links the anther to the base of the flower

Flower

Branches specialized for reproduction found in some seed-bearing plants, containing either specialized male or female organs or both male and female organs

Fruit

Thickened tissue derived from ovary wall that protects the embryo after fertilization and facilitates seed dispersal

Ginkgophyte

Gymnosperm with one extant species, the Ginko bilbao: a tree with fan-shaped leaves

Gnetophyte

Gymnosperm shrub with varied morphological feathers that produce vessel elements in its woody tissues; the phylum includes the genera Ephedra, Gnetum, and Welwitschia

Gymnosperm

Seed plant with naked seeds (seeds exposed on modified leaves or in cones)

Gynoecium

(Also, carpl) structure that constitutes the female reproductive organ

Heirloom seed

Seed from a plant that was grown historically, but has not been used in modern agriculture on a large scale

Herbaceous

Grass-like plant noticeable by the absence of woody tissue

Herbivory

Consumption of plants by insects and other animals

Integument

Layer of sporophyte tissue that surrounds that megasporangium, and later, the embryo

Megasporocyte

Megaspore mother cell; larger spore that germinates into a female gametophyte in a heterosporous plant

Microsporocyte

Smaller spore that produces a male gametophyte in a heterosporous plant

Monocots

Related group of angiosperms that produce embryos with one cotyledon and pollen with a single ridge

Monoecious

Describes a species in which the male and female reproductive organs are on the same plant

Nectar

Liquid rich in sugars produced b flowers to attract animal pollinators

Ovary

Chamber that contains and protects the ovule or female megasporangium

Ovulate cone

Cone containing two ovules per scale

Ovule

Female gametophyte

Paraphyletic group

Not all descendents of a single common ancestor are included in the group

Perianth

Part of the plant consisting of the calyx (sepals) and corolla (petals)

Petal

Modified leaves interior to the sepals; colorful petals attract animal pollinators

Pistil

Fused group of carpels

Pollen grain

Structure containing the male gametophyte of the plant

Pollen tube

Extension from the pollen grain that delivers sperm to the egg cell

Pollination

Transfer of pollen from the anther to the stigma

Progymnosperm

Transitional group of plants that resembled conifers because they produced wood, yet still reproduced like ferns

Sepal

Modified leaf that encloses the bud; outermost structure of a flower

Spermatophyte

Seed plant

Stamen

Structure that contains the male reproductive organs

Stigma

Uppermost structure of the carpel where pollen is deposited

Strobilus

Plant structure with a tight arrangement of sporophylls around a central stalk, as seen in cones or flowers; the male strobilus produces pollen, and the female strobilus produces the eggs

Style

Long, thin structure that links the stigma to the ovary

At what stage does the diploid Zygote form?

At fertilization

If a flower lacked a megasporangium, what type of gamete would not form? If the flower lacked a microsporangium, what type of gamete would not form?

f a flower lacked a megasporangium, it would not produce egg cells (female gametes). If it lacked a microsporangium, it would not produce sperm cells (male gametes).

Seed plants are

All heterosporous

Besides the seed, what other major structure diminishes a plant’s reliance on water for reproduction?

Pollen

In which of the following geological periods would gymnosperms dominate the landscape?

Permian

Which of the following structures widens the geographic range of a species and is an agent of dispersal?

Seed

Which of the following traits characterizes gymnosperms?

The plants carry exposed seeds on modified leaves

Megasporocytes will eventually produce which of the following?

Female gametophytes

What is the policy of the following structures: gametophyte, seed, spore, sporocyte?

1n, 2n, 1n, 2n

In the northern forests of Siberia, a tall tree is most likely a:

Conifer

Which of the following structures in a flower is not directly involved in reproduction?

The sepals

Pollen grains develop in which structure?

The anther

In the course of double fertilization, one sperm cell fuses with the egg and the second one fuses with _________.

The polar nuclei of the center cell

Corn develops from a seedling with a single cotyledon, displays parallel veins on its leaves, and produces monosulcate pollen. It is most likely a:

A monocot

Which of the following plant structures is not a defense against herbivory?

Nectar

White and sweet-smelling flowers with abundant nectar are probably pollinated by:

Bees and butterflies

Abundant and powdery pollen produces by small, indistinct flowers is probably transported by:

Wind

Plants are a source of ________.

a food

b fuel

c medicine

d all of the above

d all of the above

Because insects pollinated flowers and flowers provided food, both benefited—leading to mutual adaptations like flower shapes and insect feeding structures.

What role did seed and pollen adaptations play in seed plant expansion?

Seeds protect embryos and allow dormancy; pollen allows fertilization without water, enabling reproduction in diverse environments.

What adaptation makes conifers suited to Mediterranean climates?

Their needle-like leaves reduce water loss, making them drought-resistant—ideal for dry, hot summers.

What are the four modern phyla of gymnosperms?

Coniferophyta, Cycadophyta, Ginkgophyta, and Gnetophyta.

How can a botanist tell cycads from palm trees?

Cycads have cone-bearing structures and unbranched trunks with stiff leaves; palms have flowers and fruits, not cones.

What two structures help angiosperms dominate land ecosystems?

Flowers (for pollination) and fruits (for seed protection and dispersal).

Why do plants invest so much energy in attracting pollinators?

Animal pollination increases efficiency, genetic diversity, and chances of successful fertilization over long distances.

What is biodiversity and why is it important?

Biodiversity is the variety of life in an ecosystem; it boosts resilience, stability, and productivity by supporting complex food webs and adaptation.