Midterm 2 Flashcards
Syntrophy
When one organisms by-product is a food source for another organism. (Non-oxygen phototrophs)
Endocytosis
The process by which cells take in substances from outside of the cell by engulfing them in a vesicle
Phagocytosis
The ingestion of bacteria or other material by phagocytes and amoeboid protozoans
Gram-
Has peptidoglycan and a membrane
Primary endosymbiosis
Occurs when a prokaryote is merged with a eukaryote
Secondary/tertiary endosymbiosis
Occur when a eukaryote engulfs another eukaryote
Rhyzaria
Unicellular, aquatic, have long thin pseudopodia
Plasmodesmata
A narrow thread of cytoplasm that passes through the cell walls of adjacent plant cells and allows communication between them
Glaucophytes
Freshwater, unicellular algae that have a layer of peptidoglycan in their chloroplast
Diploid
2n
Haploid
n
Diplontic life cycle
Multicellular, diploid adult stage. All animals.
Gametes (male/female n)-> fertilization (2n)-> Zygote (2n) -> Mature organism (2n) -> Meiosis -> Gametes (n)
Haplontic life cycle
Lacks a multicellular diploid (2n) stage. Most algae have a haplontic life cycle.
Poikilohydry
The capacity to tolerate dehydration and to recover from it without physiological damage
Bryophytes
Small non-vascular plants that live in cool, moist environments. They lack true leaves, roots and xylem and phloem. Carry water by diffusion (high to low concentrations)
Mycorrhizae
Fungi that have a symbiosis with land plants; they increase surface area and allow for greater water absorption.
Archegonia
Produces eggs
Antheridia
Produces sperm
Sporophyte
Produces airborne spores; they are resistant to desiccation because of sporopollenin. Sporopollenin coats the outside of spores to reduce water loss
Homospory
The production of asexual spores of only one kind
Heterospory
The production of two types of spores differing in size and sex
A modification of the plant life cycle where there are two sizes of spores. Each size of spore develops into a different gametophyte.
Liverwort
Short, stalked gametophyte with a very small sporophyte
Hornworts
Persistently green sporophyte with indeterminate growth
Tracheid
Tissue that conducts water. A type of xylem tissue
Vessel elements
Evolved later, are larger and more efficient. They are connected end-to-end
Sieve tube elements
Specialized cells important for the function of phloem
Lycophytes
Vascular plants that have microphylls and strobili. They do not produce seeds
Microphylls
Small structures that have a single vein of vascular tissue
Sporangia
Clusters of spore-producing structures. A linear cluster of sporangia is called a strobilus (cone)
Euphyllophytes
All vascular plants that have large, vascularized leaves (megaphylls). All share inversions of the order of chloroplast DNA
Sorii
Clusters of sporangia that produce and “fling” spores
Seed plants
They all have secondary growth and make seeds. All seed plants are heterosporous. Share four important innovations: seeds, pollen, secondary growth, heterospory
Seed
Seeds contain embryos which germinate under favorable conditions. A seed contains an embryo and nutritive tissue, protected by a seed coat.
They share three things: embryo (2n), seed coat (2n), and nutritive tissue (n or 3n)
Gymnosperms
Include cycads, ginkgo, gmetophyte, and conifers. Their seeds lack ovaries and are not enclosed by fruit.
Gymnosperm = naked seed
Two types of cones. Woody cones = megasporangia. Leafy cones = microsporangia
Unlike non-seed plants, spores develop into gametophytes in place and never leave the parent plant
Pollen transfers a perm to the egg using a pollen tube
Cycads
Characterized by having large, compound leaves and separate make and female plants (dioecious)
Reproduction involves swimming a perm which exits the pollen tube and swim a short distance.
Only gymnosperm pollinated by insects. All others are pollinated by wind
Gnetophytes
Only have three genera (Welwistchia, Ephedra, Gnetum). They are characterized by having paired, opposite leaves, vessel elements, and double fertilization.
Serotiny
An adaptation in plants where seeds are only released when there is an environmental trigger; the most famous is fire.
Nitrogen deficiency
Stunts growth. Results in a yellow plant.
Phosphorous deficiency
Stunts growth. Red/purple tint
Angiosperms
Have flowers, double fertilization (3n endosperm) and vessel elements
Reproduction involves flowers and other pollination strategies.
Have both tracheids and vessel elements
Perfect flower
Has both stamens and carpels
Monoecious
If one plant has both sexes
Dioecious
Two plants (one per sex)
Simple fruit
A fruit that has many seeds but develops from a single carpel.
Aggregate fruit
Result from several independent carpels on a single flower
Multiple fruits
The result of the fusion of multiple flowers (carpels)
Accessory fruits
Have some of their flesh derived from outside the ovary.
