Flower and Seed Structure in Angiosperms and Gymnosperms

These flashcards cover key concepts related to flower and seed structures, comparing gymnosperms and angiosperms, and various plant adaptations.

What is the pistil and what are its parts?

The pistil is the female reproductive structure of a flower made of stigma, style, ovary, and ovules.

What is the function of the stigma in a flower?

The stigma is the sticky tip at the top of the pistil that traps pollen grains during pollination.

What is the role of the style in a flower?

The style is a tube-like structure connecting the stigma to the ovary, acting as a pathway for the pollen tube.

What does the ovary do in a flower?

The ovary is the enlarged base of the pistil that contains ovules and develops into fruit after fertilization.

What is an ovule, and what does it become after fertilization?

An ovule is located inside the ovary, contains the female gamete (egg), and becomes the seed after fertilization.

What is the stamen and its parts?

The stamen is the male reproductive structure made of anther and filament, producing and supporting pollen.

What is the function of the anther in a flower?

The anther is located at the tip of the stamen and produces pollen grains (male gametophytes).

What is the purpose of the filament in a flower?

The filament is a thin stalk that holds the anther up for effective pollen transfer.

What role do petals play in flowering plants?

Petals are brightly colored structures that attract pollinators and help ensure pollination.

What are sepals, and what is their function?

Sepals are green leaf-like structures at the base of the flower that protect the developing bud.

What is the receptacle in a flower?

The receptacle is the thickened base of the flower where all parts attach and supports the flower structure.

What is a pollen tube?

A pollen tube grows from the pollen down the style into the ovule, allowing sperm cells to reach the egg for fertilization.

What is a seed?

A seed is a structure containing a plant embryo, stored food, and protective coat, allowing survival and dispersal.

What is the function of the testa (seed coat)?

The testa is the outer protective layer of the seed that protects the embryo from damage and pathogens.

What is an embryo in a seed?

An embryo is the young developing plant inside the seed that will grow into a new plant.

What are cotyledons, and how do they differ in monocots vs dicots?

Cotyledons are seed leaves that store nutrients; monocots have 1, dicots have 2.

What is the function of endosperm in a seed?

Endosperm is nutrient-rich tissue that feeds the embryo during early development.

What is a radicle?

A radicle is the embryonic root and the first structure to emerge during germination.

What is a plumule?

A plumule is the embryonic shoot that develops into the stem and leaves of a plant.

What is the role of the hypocotyl?

The hypocotyl is the region below cotyledons that helps push the seedling out of the soil during germination.

What is the epicotyl?

The epicotyl is the region above the cotyledons that develops into the upper stem and leaves.

What are the key features of gymnosperms?

Gymnosperms are seed plants with 'naked seeds' that reproduce using cones and are mostly wind-pollinated.

What are the key features of angiosperms?

Angiosperms are flowering plants with seeds enclosed in fruit, using flowers for reproduction.

What is the main difference between gymnosperms and angiosperms?

Gymnosperms have seeds exposed on cones, while angiosperms have seeds enclosed inside ovaries (fruit).

What are characteristics of monocots?

Monocots have 1 cotyledon, parallel veins, flower parts in multiples of 3, and scattered vascular bundles.

What are characteristics of dicots?

Dicots have 2 cotyledons, net-like veins, flower parts in 4s or 5s, and vascular bundles in rings.

What is pollination?

Pollination is the transfer of pollen from anther to stigma through wind, water, or animals.

What happens during fertilization in angiosperms?

During fertilization, the pollen tube delivers sperm; one sperm fertilizes the egg, and one forms endosperm.

Why is seed dispersal important?

Seed dispersal spreads seeds away from parent plants to reduce competition and allow growth in new environments.

What are gymnosperms?

Gymnosperms are seed plants with 'naked seeds' that reproduce using cones and are mostly wind-pollinated.

What are coniferophyta characteristics and examples?

Coniferophyta is the largest gymnosperm group with needle-like leaves, including pine, spruce, fir, and cedar.

What are gnetophyta characteristics?

Gnetophyta is a small, diverse group that includes Ephedra and Welwitschia, and shows an evolutionary link to flowering plants.

Why are conifers successful in cold/dry climates?

Conifers have needle leaves to reduce water loss, thick cuticles to prevent drying, and cones to protect reproductive structures.

What are cycadophyta characteristics and habitat?

Cycadophyta are tropical/subtropical plants with palm-like leaves, slow-growing, and dioecious.

What is unique about cycads' roots?

Cycads have roots that contain symbiotic cyanobacteria that help fix nitrogen.

What is the one living species of ginkgophyta?

The only living species of ginkgophyta is Ginkgo biloba.

What is a special reproductive feature of ginkgo?

Ginkgo produces seeds with a fleshy outer covering, which is not true fruit, having separate male and female trees.

Why are gnetophytes scientifically important?

Gnetophytes share features with angiosperms, suggesting a possible evolutionary connection.

What is the function of a male cone?

The male cone produces pollen (male gametophytes) and is usually small and located higher on the tree.

What is the function of a female cone?

The female cone contains ovules (female gametophytes) and is larger and located lower on the tree.

What is alternation of generations?

Alternation of generations is the life cycle that alternates between sporophyte (2N) and gametophyte (1N) stages.

What is the function of meristematic tissue?

Meristematic tissue is the site of rapid mitosis found in root and shoot tips.

Why are dark rings formed in tree rings?

Dark rings are formed from dense xylem cells during poor growth conditions.

What ploidy is a seed cone?

A seed cone is a diploid (2N) structure producing haploid (1N) gametophytes.

What is transpiration?

Transpiration is the loss of water vapor through stomata in leaves.

What is the function of stomata and guard cells?

Stomata and guard cells regulate gas exchange and water loss by opening and closing pores.

What is the difference between xylem and phloem?

Xylem transports water upwards, while phloem transports sugars in both directions.

What are the key layers in dicot leaf structure?

Key layers in dicot leaf structure include cuticle, epidermis, palisade mesophyll, spongy mesophyll, and vascular tissue.

What are the three key adaptations of land plants?

Key adaptations of land plants include cuticle for water retention, vascular tissue for transport, and lignin for support.