unit 2
Prokaryote – An organism made of a single cell with no nucleus (Bacteria and Archaea).
Protist – A eukaryotic organism that is not a plant, animal, or fungus; very diverse group.
Bacteria – Single-celled prokaryotes; one of the three domains of life.
Eukaryote – An organism whose cells contain a nucleus and membrane-bound organelles.
Fungus – Eukaryotes that absorb nutrients from their environment; includes mushrooms and molds.
Hyphae – Threadlike filaments in fungi that absorb nutrients.
Fruiting Body – The reproductive structure of fungi (like a mushroom) that makes spores.
Seedless vascular plants – Plants like ferns; have vascular tissue but do not produce seeds.
Seed – A plant embryo with a food supply and protective coat.
Gymnosperm – A seed plant (like pine trees) that produces “naked” seeds, not in fruits.
Angiosperm – A flowering plant that produces seeds enclosed inside a fruit.
Root system – Underground organs that anchor the plant and absorb water and minerals.
Shoot system – Stems and leaves that support the plant and perform photosynthesis.
Dermal tissue – The plant’s outer protective covering.
Vascular tissue – Xylem and phloem that transport water, nutrients, and sugars.
Ground tissue – Tissue for photosynthesis, storage, and support.
Stomata – Pores on leaves that allow gases to enter and exit the plant.
Sporophyte – The diploid plant stage that makes spores.
Gametophyte – The haploid plant stage that makes gametes (egg and sperm).
Spores – Haploid cells that grow into gametophytes.
Gametes – Egg or sperm cells.
Zygote – The fertilized egg formed when sperm and egg unite.
Pollen – The male gametophyte of seed plants.
Pollination – Transfer of pollen to the female reproductive part of a plant.
Flower – The reproductive structure of angiosperms.
Fruit – The mature ovary of a flower that protects seeds and helps disperse them.
🍃LECTURE: BACTERIAWhat characteristics do all living things share?
All living things are made of cells, reproduce, grow, use energy, maintain homeostasis, respond to their environment, and contain DNA.
What is a microbe? What is a prokaryote? What is Bacteria?
A microbe is any microscopic organism.
A prokaryote is a cell with no nucleus.
Bacteria are a domain of prokaryotes that live everywhere and are extremely diverse.
Why is microbial diversity important to humans?
Microbes help us digest food, protect us from harmful bacteria, make foods like yogurt and cheese, cycle nutrients in the environment, and are used to make medicines and biotechnology products.
What are the three domains of life?
Bacteria, Archaea, and Eukarya.
Two features that help bacteria evolve quickly:
Bacteria evolve quickly because they reproduce extremely fast and because they experience frequent mutations. They can also share DNA using plasmids.
🍄LECTURE: FUNGI & PROTISTSWhat are the four kingdoms in Eukaryota?
Protists, Fungi, Plants, and Animals.
What is a Protist?
Protists are eukaryotes that are NOT plants, animals, or fungi. They do not all share one unifying feature — they are simply grouped because they don’t fit into the other kingdoms.
How do fungi obtain energy?
Fungi digest food by secreting enzymes outside their bodies and then absorbing the nutrients.
Plants get energy through photosynthesis.
Animals get energy by ingesting food internally.
What are hyphae and fruiting bodies?
Hyphae are long, thin filaments that fungi use to absorb nutrients.
The fruiting body is the reproductive structure (like a mushroom) that makes spores.
🌱LECTURE: SEEDLESS PLANTS (Plant Diversity I)Where did the ancestors of land plants live? What adaptations were needed for land?
They lived in water (green algae).
To move to land, they needed a waxy cuticle to avoid drying out, stomata for gas exchange, structures for support, and (later) vascular tissue for water transport.
General plant life cycle:
The sporophyte makes spores → spores grow into gametophytes → gametophytes make gametes → fertilization makes a zygote → the zygote grows into the sporophyte.
Why do non-vascular plants need moisture? (Two reasons)
They need water because their sperm must swim to the egg, and they lack vascular tissue, so they rely on water on the plant surface to move materials.
What is vascular tissue for, and who has it?
Vascular tissue transports water (xylem) and sugars (phloem). Ferns, gymnosperms, and angiosperms have vascular tissue.
Why do seedless vascular plants need moisture? (One reason)
Their sperm still must swim to the egg.
How does a fern’s life cycle differ from moss?
In mosses, the gametophyte is the dominant, larger stage.
In ferns, the sporophyte is the dominant, larger stage.
🌲LECTURE: SEED PLANTS (Plant Diversity II)Two major adaptations that gymnosperms have over ferns:
Gymnosperms produce pollen and seeds.
These allow them to live in dry environments because fertilization does NOT require water, and seeds protect embryos from drying out.
What is an angiosperm?
Angiosperms are flowering plants. They have flowers and fruits, which distinguish them from gymnosperms.
Monocots vs. dicots:
Monocots have one seed leaf, parallel veins, and flower parts in multiples of 3.
Dicots have two seed leaves, branching veins, and flower parts in multiples of 4 or 5.
What is pollination, and how do animals help?
Pollination is the transfer of pollen to the female part of a plant.
Animals carry pollen from flower to flower while collecting nectar.
Why use animal pollination?
It is more accurate and more efficient than wind pollination, requiring fewer pollen grains and increasing reproductive success.
What part becomes the fruit?
The ovary of the flower matures into the fruit.
Why do plants produce fruits?
Fruits protect the seeds and help disperse them — often by animals eating the fruit and carrying the seeds elsewhere.
Place major adaptations on a plant evolutionary tree:
Waxy cuticle – earliest land plants (prevents drying).
Vascular tissue – seedless vascular plants and beyond.
Pollen – gymnosperms and angiosperms.
Seeds – gymnosperms and angiosperms.
Fruit – only angiosperms.
🌼LECTURE: PLANT ANATOMYTwo organ systems and three organs in plants:
Organ systems: root system and shoot system.
Organs: root, stem, leaf.
Roots absorb water/minerals and anchor the plant.
Stems support the plant and transport materials.
Leaves perform photosynthesis.
Three types of tissue in each organ:
Dermal tissue: protection.
Vascular tissue: transport.
Ground tissue: photosynthesis, storage, support.
What are stomata? What do they do?
Stomata are tiny pores on leaves that open and close to allow gas exchange (CO₂ in, O₂ out) and help regulate water loss.