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What domain does this organism belong to: Prokaryote
No natural selection
The science of biological nomenclature and classification
Describing, naming, and classifying living and extinct organisms and viruses
Hypothesis of the evolutionary history of a species or group of species based on morphological or genetic data
Occurs when selection causes differential survival of a particular phenotype
Form of natural selection directed at traits of sexual species that makes it more likely for individuals to find a mate/successfully mate
Advantage that certain individuals have over others of the same sex & species with respect to reproduction only
Includes a most recent common ancestor and all of its descendants
Also called a clade
Includes a most recent common ancestor and only some of its descendants
Also called a grade
Species change over time
Species are related through descent from a common ancestor
Biological change is driven by observable forces
Homology (Anatomical, Developmental, Molecular)
Observation of evolutionary change
Cell Theory (all living things made of cells, the simplest units of life, come from other cells)
Gene Theory (DNA in genes code for proteins)
Theory of Inheritance (change in DNA produces heritable variation)
Theory of Evolution
Programs and procedures designed to modify traits in domesticated species.
Made possible by genetic variation
Desirable phenotypes are chosen - nature chooses in natural selection, breeders choose in artificial selection.
Chlorophyta - many forms (unicellular, filamentous, colonies, leaves, etc)
Charophyta - aka stoneworts d/t Ca salt often precipitated on surface. Closest to plants (high cellulose in cell wall, reproductive characteristics, similar growth patterns)
Increased cellular organization and specialization
Shift from isogamous (male/female gametes appear the same) to oogamous (male small and motile, female large and stationary) reproduction
Diploid: zygote undergoes mitosis to form sporophyte, which produces sporocyte/sporangium.
Haploid: Sporocyte undergoes meiosis to produce spores, which develop into gametophytes that produce gametes by mitosis, which fuse in fertilization./syngamy
Reproductive: alt of gen, embryos depend on maternal tissue during early development, specialized structures to generate/protect/disperse reproductive cells
3D tissues arise from apical meristems, help prevent water loss
Simplest plants, include liverworts, mosses, hornworts
Gametophyte generation dominant
Sporophytes dependent on gametophyte
Nonvascular (lacking tissues for structural support and conduction)
Seedless vascular plants, include ferns. Leaves are megaphylls
All vascular plants, seedless or seed-producing
Help with water and mineral conduction and structural suport
Sporophyte is conspicuous phase. Fronds appear coiled in fiddlehead, then unroll and expand. Fronds often divided into segments called pinnae, attached to the midrib.
Sporangia on lower leaf, may be in clusters (sori). Annulus catapults them out.
Gametophytes have both female and male parts
Male and female gamete-producing structures are on separate gametophytes
Allow plants to survive adverse conditions
Protect and provide energy for embryos (contain food supply)
Can live for an extended period of time
Contain a multicellular, well-developed young plant w/ embryonic root, stem, and leaves
Sporophyte is dominant stage
Heterospory - megaspores (female) and microspores (male). Microspores pollinated by wind or animals
Woody stems and bark, reduced leaves, waxy cuticle
The ovule/megasporangia consists of megagametophyte & nucellus, enclosed by integument (will become seed coat). Each ovule produces a megaspore mother cell, which forms 4 cells by meiosis. One becomes megaspore, develops into megagametophyte.
Dioecious - male cone (microstrobilus), female cone (megastrobilus)
Nonwoody stems may emerge or be underground
Produce toxins to deter predators
Cones emit odors that attract beetles, which carry pollen to ovules
Dioecious - individual trees produce either ovules and seeds or pollen
Widely planted along city streets (only males d/t stinky seeds)
Nearly extinct in the wild
Simple pollen cones, complex ovule-bearing cones
Cone opens up as it matures and mature pollen is released to the wind
Seed coats may develop wings for wind dispersal or bright, fleshy coatings to attract animals
Flexible branches help shed snow
Scale/Needle-like leaves resist damage from drought
Thick waxy cuticle reduces water loss and protects from attack of disease-causing organisms
Gnetum: tropical vines with broad leaves
Welwitschia: one living species. long taproot and two very long leaves
Ephedra: shrubby plants in arid climates
Angiosperm Defining Features
Fruits with enclosed seeds
Seeds enclosed in carpel that resembles a folded and fused leaf. Pistil composed of a carpel or 2+ united carpels. Seed develops from ovule within the carpel. Ovary becomes a fruit.
petals (attractive, play a role in pollination) and sepals (green and form the outer layer of the flower). both referred to as tepals when they look alike.
In pollination, pollen grains released from anthers find their way to a compatible flower's stigma. Some plants self-pollinate, some cross-pollinate.
Fertilization is the union of sperm and egg.
Archegonia (eggs) clustered under notch, Antheridia (sperm) scattered
Monocots have 1 cotyledon, Dicots have 2
M flower parts in 3s, D in 4s/5s
M have parallel venation, D network of veins
M dont have vascular nor cork cambium, D do
M vascular bundles scattered, D in ring
M pollen has 1 aperture, D has 3
Anchor plant into soil
Absorb water and nutrients
Store food and water
Provide support for leaves and reproductive structures
Conduct water and nutrients
Produces primary and secondary growth
Some produce food, some store water/food
Wastes from metabolic processes accumulate in leaves and are disposed of when leaves are shed
Tiny pores on surface of leaves that allow CO2 to enter and O2/H20 to exit
Mostly on bottom surface of eudicots, only on top of floating plants, both for monocots
Control water loss by opening and closing the pore of the stomatal apparatus
Apical Meristem (Region of cell division)
Region of elongation
Region of maturation (root hairs form here, absorb water and minerals, adhere to soil, increase absorptive surface area of root)
Epidermis: outer layer of cells; protect root
Cortex: ground tissue protecting vasc tissue. Store photosynth products, uptake water/minerals
Endodermis: layer of cortex regulating H2O flow of vasc tissue
Pericycle: in endodermis, 2ndary root prod.
Complex reproductive structure specialized for efficient production of pollen and seeds. Produced at stem tips.Sepals, petals, stamens, carpels
Ovary and its accessory parts that's developed/matured.
Aid in dispersal of enclosed seeds. Dispersal prevents competition, aids in colonization. Adaptations attract animals to eat them, help w/ wind dispersal, catch in animal fur, float in water.
Endocarp: inner boundary around seed(s)
Mesocarp: tissue between exocarp and endocarp
Pericarp: exocarp, endocarp, and mesocarp collectively
Simple fleshy: develop from flower with single carpel or several fused carpels
Dry simple: mesocarp is dry at maturity. may be dehiscent (split at maturity) or indehiscent (doesn't split at maturity)
Develops when many ovaries in an inflorescence fuse together. Attract large animals that have the ability to disperse seeds for long distances
Wind: fruit (samaras, plumes, hairs) or seeds (small, lightweight, wings)
Animals: seeds pass through digestive tract or fruits/seeds adhere to fur or feathers
By forcible discharge
Herbaceous Dicot Stem
Vascular bundles arranged in a cylinder, Vascular cambium arises between primary X & P, creates secondary X & P
Monocot StemVascular bundles scattered, oriented with xylem towards inside and phloem towards outside. No secondary vascular tissues or cork.
Woody Dicot Stem
Annual xylem rings, vascular cambium between primary X & P, cork cambium present, outer layer of cork present
If vascular/cork cambium active all yr, ungrained/uniform wood produced
If wood produced seasonally
Spring: large tracheids & vessels of 2ndary xylem produced.
Summer: smaller vessels compared to tracheids & fibers.
No vessels/fibers in conifers
Tissues outside the vascular cambium, including the secondary phloem
Inner bark: primary and secondary phloem
Outer bark: cork tissue and cork cambium
Bud located in axil. Will become branches or flowers. Bud scales protect the buds
Blade divided into leaflets
Leaflets in pairs along rachis (petiole)
All leaflets attached at same point at end of petiole
One leaf per node
Two leaves per node
Three or more leaves per node
Veins parallel to one another
Main midvein included within enlarged midrib, secondary veins branch from midvein
Several primary veins fan out from the base of the blade
Palisade: compactly stacked, barrel shaped parenchyma cells, commonly in two rows. Near the upper epidermis. Contains most of the leaf's chloroplasts
Spongy: loosely arranged parenchyma cells with abundant air spaces. Also has chloroplasts
Not differentiated into palisade and spongy layers.
Often have bulliform cells on either side of the main central vein. They partly collapse under dry conditions, causing the leaf to fold or roll, reducing transpiration.
Separated into palisade and spongy mesophyll layers
Mesophyll not separated into 2 layers.
Male reproductive part at the end of the stamen that produces pollen
Stele very small, xylem arranged in an X formation with phloem surrounding
Stele large, xylem arranged in a circle with phloem surrounding
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