Seed Plants, Fungi, and Animal Diversity: Key Concepts and Phyla

What is a seed?

A plant embryo with stored food and a protective coat.

What is pollen?

Male gametophyte that delivers sperm without water.

What is a flower?

Reproductive structure of angiosperms that attracts pollinators and produces gametes.

What is a fruit?

Mature ovary containing seeds; aids seed dispersal.

What are secondary metabolites?

Chemicals not required for basic survival but used for defense, attraction, and survival.

What is pollination?

Transfer of pollen from anther to stigma (in flowering plants).

What is fertilization in plants?

Fusion of sperm and egg inside the ovule → forms zygote.

What is a pollination syndrome?

Traits of flowers adapted to specific pollinators.

What is coevolution?

Reciprocal evolutionary changes between interacting species (e.g., flowers & pollinators).

What major evolutionary change separates seed plants from seedless plants?

Seeds and pollen replace dependence on water for reproduction.

What is cross-pollination?

Pollen from one flower fertilizes a flower on another plant.

Why are flowering plants the most successful plant group on land?

Flowers attract pollinators; fruits enhance seed dispersal; coevolution increases diversity.

How are seed plants important for humans?

Provide food, medicine, building materials, oxygen, and ecosystem services.

Define gymnosperm.

Seed plants whose seeds are not enclosed in a fruit; often in cones.

What are the characteristics of Phylum Cycadophyta?

Palm-like, large cones; ancient group.

What is an example of Phylum Ginkgophyta and its trait?

Ginkgo biloba; fan-shaped leaves; pollution tolerant.

What are the traits of Phylum Coniferophyta?

Cone-bearing, needle leaves; examples: pines, firs, redwoods.

What is Phylum Anthophyta?

Flowering plants; produce flowers and fruits.

What unique trait do angiosperms have?

Double fertilization (produces embryo + endosperm).

What is a hypha?

Filament of fungal cells.

What is mycelium?

Network of hyphae that absorbs nutrients.

What is a fruiting body?

Spore-producing reproductive structure (e.g., mushroom).

How do fungi reproduce asexually?

By budding or producing spores via mitosis.

How do fungi reproduce sexually?

Fusion of hyphae (plasmogamy), then nuclei fuse (karyogamy), producing spores.

What is chytridiomycosis?

Fungal disease killing amphibians.

Why is Kingdom Fungi called the 'invisible kingdom'?

Most fungal biomass is underground and unseen.

How do fungi differ from animals?

Fungi absorb food externally; animals ingest food.

Name examples of fungi.

Mushrooms, yeasts, molds, Penicillium.

Describe a mutualistic fungus-plant relationship.

Mycorrhizae: fungi help plants absorb nutrients; plants give sugars.

Describe a mutualistic fungus-animal relationship.

Leafcutter ants grow fungi for food.

What are animals?

Multicellular, heterotrophic, eukaryotic organisms that ingest food.

What is the Cambrian explosion?

Rapid diversification of animal body plans ~540 million years ago.

What is a tissue?

Groups of specialized cells performing specific functions.

What is radial symmetry?

Body arranged around a central axis (e.g., jellyfish).

What is bilateral symmetry?

Two-sided symmetry; associated with movement and cephalization.

Define coelom.

Body cavity lined with mesoderm.

What is a zygote?

Fertilized egg.

What is cleavage?

Rapid cell division after fertilization.

What is the difference between spiral and radial cleavage?

Spiral (protostomes), radial (deuterostomes).

What is the difference between determinate and indeterminate cleavage?

Determinate: cell fate fixed early; indeterminate: cells can form whole organism (twins).

What is a blastula?

Hollow ball of cells.

What is gastrulation?

Formation of germ layers.

What is a gastrula?

Stage with ectoderm, mesoderm, endoderm.

What are embryonic stem cells?

Undifferentiated cells able to become any cell type.

What is cloning?

Producing a genetically identical organism.

What is de-extinction?

Attempt to revive extinct species using genetic technology.

What is biomimicry?

Designing solutions inspired by nature.

What are invertebrates?

Animals that lack a backbone.

What are the characteristics of Phylum Porifera?

No true tissues; filter feeders. Example: sponges.

What are the characteristics of Phylum Cnidaria?

Radial symmetry, stinging cells. Examples: jellyfish, corals, hydras.

What are the characteristics of Phylum Platyhelminthes?

Flatworms; bilateral; acoelomate. Examples: planarians, tapeworms.

What are the characteristics of Phylum Syndermata?

Rotifers; pseudocoelomate; crown of cilia. Examples: rotifers.

What are the characteristics of Phylum Mollusca?

Soft-bodied, often shelled; foot, mantle. Examples: snails, clams, squid.

What are the characteristics of Phylum Annelida?

Segmented worms; closed circulatory system. Examples: earthworms, leeches.

What are the characteristics of Phylum Nematoda?

Roundworms; tough cuticle. Examples: C. elegans, parasitic worms.

What are the characteristics of Phylum Arthropoda?

Exoskeleton, jointed limbs, segmented body. Examples: insects, spiders, crustaceans.

What are the characteristics of Phylum Echinodermata?

Radial (adult), water vascular system. Examples: starfish, sea urchins.

Invertebrate chordates belong to what phylum?

Phylum Chordata (tunicates & lancelets).