EXAM I Vocab Flashcards
CAM
C4 plants that open their stomata at night to take up carbon dioxide. // CAM - Crassulacean Acid Metabolism CAM plants - Very well adapted to dry conditions – desert plants and succulents - Open stomata at night, close during day - Store CO 2 as C 4 acids (malate) for release and fixation during the day CAM Plants Fig. 8.19 - Stomata open during cool nights – CO 2 comes in and fixed into C4 acid - C4 acids stored in vacuoles - Stomata close during hot day - C4 acids exported to chloroplast,
3-phosphoglycerate
Carbon Fixation (Phase 1) In carbon fixation, CO 2 becomes incorporated into ribulose bisphosphate (RuBP), a five-carbon sugar. The product of the reaction is a six-carbon intermediate that immediately splits in half to form two molecules of 3-phosphoglycerate (3PG). The enzyme that catalyzes this step is named RuBP carboxylase/oxygenase, or rubisco. It is the most abundant protein in chloroplasts and perhaps the most abundant protein on Earth This observation underscores the massive amount of carbon fixation that happens in the biosphere. Reduction and Carbohydrate Production (Phase 2) In the second phase, ATP is used to convert 3PG to 1,3-bisphosphoglyc- erate. Next, electrons from NADPH reduce 1,3-bisphosphoglycer- ate to glyceraldehyde-3-phosphate (G3P). G3P is a carbohydrate with three carbon atoms. The key difference between 3PG and G3P is that G3P has a C—H bond, whereas the analogous carbon in 3PG forms a C—O bond (Figure 8.15). The C—H bond can occur because the G3P molecule has been reduced by the addi- tion of two electrons from NADPH.
Absorption /Action spectrum
The absorption spectrum plots a pigments ability to absorb light against wavelength; the action spectrum plots photosynthetic rate against wavelength Absorption: A diagram that depicts the wavelengths of electromagnetic radiation that are absorbed by a pigment. Action: The rate of photosynthesis plotted as a function of different wavelengths of light.//
Adventitious roots
A root that is produced on the surfaces of stems (and sometimes leaves) of vascular plants; also, roots that develop at the bases of stem cuttings.
Aggregate fruit
Aggregate fruits - Develop from a cluster of separate carpels - Each flower contains many ovaries - E.g. strawberry, blackberry, magnolia, raspberry // Differences in the shape, color, fragrance, and moisture content of wild fruits reflect evolutionary adaptation for effec- tive seed dispersal. Though many fruits and seeds are dispersed by wind or water or by attaching to animal fur, others are con- sumed by fruit-eating animals that are attracted by fruit color and fragrance. Blackberries provide a good example of fruits adapted for animal dispersal. Blackberry flowers produce many separate pistils, each containing a single ovule (Figure 39.19a). Following pollination and fertilization, the ovary of each pistil develops into a sweet, juicy fruitlet containing a single seed. As the individual fruitlets develop, they fuse together at the sides. Consequently, the many fruitlets produced by a single black- berry flower are dispersed together, in a structure known as an aggregate fruit (Figure 39.19b). Attracted by the color, birds consume the whole aggregate and excrete the seeds, thereby dispersing many at a time. Many other types of fruits occur and these likewise represent adaptations that foster seed dispersal (refer back to Figure 30.21). Although a fruit is usually defined as a mature ovary containing seeds, commercial seedless fruits such as watermelon are produced by genetic modification or treatment with artificial auxin. Strawberries are aggregate fruits, many fruits that all develop from a single flower having multiple pistils
Algae
(singular, alga) A term that applies to about 10 phyla of protists that include both photosynthetic and nonphotosynthetic species; often also includes cyanobacteria.
Alternation of generations
The phenomenon that occurs in plants and some protists in which the life cycle alternates between multicellular diploid organisms, called sporophytes, and multicellular haploid organisms, called gametophytes.
Angiosperm
A flowering plant. The term means enclosed seed, which reflects the presence of seeds within fruits.
Annual
A plant that dies after producing seed during its first year of life.
Anther
The uppermost part of a flower stamen, consisting of a cluster of microsporangia that produce and release pollen.
Antheridia
Round or elongate gametangia that produce sperm in plants.
Apical
- The region of a plant seedling that produces the leaves and flowers.
Apical meristem
In plants, a group of actively dividing cells at a growing tip.
Apomixis
A natural asexual reproductive process in which plant fruits and seeds are produced in the absence of fertilization.
Archegonia
Flask-shaped plant gametangia that enclose an egg cell.
Archegonium
Bryophyte: The sperm-producing gametangium is the antheridium and the egg-producing gametangium is the archegonium.
Asexual reproduction
A reproductive strategy that occurs when offspring are produced from a single parent, without the fusion of gametes from two parents. The offspring are therefore clones of the parent
ATP
A molecule that is a common energy source for all cells.
Axillary
- axillary bud A bud that occurs in the axil, the upper angle where a twig or leaf emerges from a stem. 2. axillary meristem A meristem produced in the axil, the upper angle where a twig or leaf emerges from a stem. Axillary meristems generate axillary buds, which can produce flowers or branches.
Bryophyte
Liverworts, mosses, and hornworts, the modern nonvascular land plants.
C4 metabolism
C4 plant A plant that uses PEP carboxylase to initially fix CO2 into a four-carbon molecule and later uses rubisco to fix CO2 into simple sugars; an adaptation to hot, dry environments.
Calvin (C3) cycle
C3 plant A plant that incorporates CO2 into organic molecules via RuBP to make 3PG, a three-carbon molecule.
Carboniferous
Carboniferous - Dominance of woody lycopods – 350 mya - Extensive coal deposits form from plants growing in the carboniferous (fossils in coal)
Carotenoid
A type of photosynthetic or protective pigment found in plastids that imparts a color that ranges from yellow to orange to red.
Carpel
A flower shoot organ that produces ovules that contain female gametophytes. // Fruits form from the carpel - The carpel is composed of : - the ovary (lower part) - the style (middle part) - the stigma (top part) - The carpel develops into the fruit wall (pericarp) after fertilization
Cell wall
A relatively rigid, porous structure located outside the plasma membrane of prokaryotic, plant, fungal, and certain protist cells; provides support and protection. // Cell walls – primary and secondary, middle lamella // Cell walls Fig. 10.13 - Primary cell wall – flexible, cellulose - Secondary cell wall – cellulose, lignin, other components
Cellulose
The main macromolecule of the primary cell wall of plants and many algae; a polymer made of repeating molecules of glucose attached end to end.
Chara
Characean green algae – ancestors of Land Plants
Chemical energy
The potential energy contained within covalent bonds in molecules. // Chemical energy from the light reactions (ATP, NADPH), are used by the light-independent (dark) reactions to fix CO 2 to organic C (sugar) Calvin Cycle for CO 2 fixation Fig. 8.15
Chlorophyll
chlorophyll A photosynthetic green pigment found in the chloroplasts of plants, algae, and some bacteria. chlorophyll a A type of chlorophyll pigment found in plants, algae, and cyanobacteria. chlorophyll b A type of chlorophyll pigment found in plants, green algae, and some other photosynthetic organisms. // Chlorophyll - light harvesting, action spectra
Chloroplast
A semiautonomous organelle found in plant and algal cells that carries out photosynthesis. // - Typical leaf palisade cell contains 30 – 40 chloroplasts - Cell is 30-40 um diam. = 0.00004 m - Chloroplast is 2-10 um diam = 0.000002 m Green chlorophyll pigment in chloroplasts Light spectrum (wavelength - energy) Fig. 8.4 - Why are leaves Green? - Chloroplasts reflect green, absorb red and blue light (source of light for photosynthesis)
Climate change
GLOBAL CLIMATE CHANGE - Increasing atmospheric CO 2 conc. - useful for photosynthesis? - Increasing temperature – plant stress? - Changing precipitation patterns – water availability for plants? - Availability of other nutrients? - Biological mitigation strategies – all involve photosynthesis
Co-evolution
The process by which two or more species of organisms influence each other’s evolutionary pathway.
Cold stratification
Seed Dormancy (during dispersal) - Dormancy – a period of inactivity during which growth ceases – Breaking dormancy – plant resumes growth if moisture, temperature or day length requirements right – best chance that seeds will germinate at good time - Desert – after rain - Cold climate – in spring (cold stratification)
Collenchyma
collenchyma cells Flexible cells that make up collenchyma tissue. collenchyma tissue A plant ground tissue that provides support to plant organs. // Fig. 35.7 - Thick primary walls Usually grouped in strands or cylinders - Can elongate and expand with stem and leaf growth - Alive at functional maturity - Function – flexible support for herbaceous and young woody plants
Companion cells
Companion cells – alongside each sieve tube member - Plasmodesmata connect sieve tube member to companion cell - Companion cell nucleus serves sieve tube member Phloem – sieve elements and companion cells, sieve plates – solutes from leaves and around the plant
Compound leaf
A compound leaf divided into leaflets.
Cone
Seeds and pollen on separate strobili (cones) of sporophylls // Sporangia located in cones - Heterosporous – male and female gametes develop from separate cones
conifer
conifers A phylum of gymnosperm plants, Coniferophyta.
Cork cambium
A secondary meristem in a plant that produces cork tissue. (BARK)
Corolla
The petals of a flower, which occur in the whorl to the inside of the calyx and the outside of the stamens.
Corolla tube
Flowers pollinated by moths - Open at night - White or pale - Heavy fragrance - Corolla tube (fused petals) as long as tongue of moth
Cotyledons
Seeds - Consist of seed coat, endosperm, embryo - Endosperm (3n) – Rich in nutrients for developing embryo – In many dicots, food reserve of endosperm is restocked in cotyledons, so mature seed will lack endosperm Monocots and Dicots Fig. 39.18. 39.21 Cotyledons – ‘seed leaves’ DICOTS - Two cotyledons e.g. peanut, bean MONOCOTS - One cotyledon e.g. Corn kernel
Crassulacean acid metabolism
CAM - Crassulacean Acid Metabolism CAM plants - Very well adapted to dry conditions – desert plants and succulents - Open stomata at night, close during day - Store CO 2 as C 4 acids (malate) for release and fixation during the day CAM Plants Fig. 8.19 - Stomata open during cool nights – CO 2 comes in and fixed into C4 acid - C4 acids stored in vacuoles - Stomata close during hot day - C4 acids exported to chloroplast,
Cuticle
A coating of wax and cutin that helps to reduce water loss from plant surfaces. Also, a nonliving covering that serves to both support and protect an animal.
cycad
A phylum of gymnosperm plants, Cycadophyta. // Division Cycadophyta – The Cycads Fig. 30.3 Common in fossil record – contemporary with dinosaurs Currently 100 species – tropical and warm temperate Palm-like leaves Seeds and pollen on separate strobili (cones) of sporophylls Male and female strobili on different individuals - dioecious Macrozamia –Australian cycad
Cytoplasm
Cytoplasm: Site of metabolism. Plasmodesmata Fig. 10.14 - cytoplasmic channels that pass through pores in primary and secondary cell walls
Deciduous angiosperms
Cool Temperate forests - Dominated by deciduous angiosperms Perennials common on forest floor - Spring ephemerals - grow and flower rapidly in spring before shaded out by trees - Very few annual species
Dehiscent
Fruit types - Simple – Fleshy e.g. apricot – Dry e.g. oak – Dehiscent – tissues of mature ovary wall break open releasing seeds e.g. birch – Indehiscent – seeds remain in fruit after fruit is shed from parent plant e.g. apple Simple Dehiscent – tissues of mature ovary wall break open releasing seeds e.g. birch
Dendrochronology
Dendrochronology – determine age of wood (art fraud – picture frames, wooden musical instruments) e.g. Lindbergh kidnapping (1932) - wood anatomist matched wood from a floorboard in the home of the accused to a repaired ladder left at the crime scene
Dermal tissue
The covering on various parts of a plant. // Dermal tissue - Epidermis – single layer of tightly packed cells - Cuticle – waxy coating secreted by epidermis of leaves and stems to conserve water - Root hairs – specialized epidermal cells for water and mineral absorption
Desert plants
CAM - Crassulacean Acid Metabolism CAM plants - Very well adapted to dry conditions – desert plants and succulents - Open stomata at night, close during day - Store CO 2 as C 4 acids (malate) for release and fixation during the day CAM Plants
Determinate plant growth
Plant Growth - Determinate – organism stops growing after it reaches a certain size (e.g. humans) Meristems – apical and lateral; indeterminate plant growth
Dicot
Monocots vs Dicots vascular system Dicots – net veination Monocots – parallel veination Flower form: Monocots – 3s, Dicots – 4,5s DICOTS - Two cotyledons e.g. peanut, bean
Dioecious
The term to describe plants that produce staminate and carpellate flowers on separate plants // Dioecious – male and female plants separate (must outcross)
Dioecy
Monoecy and dioecy Monoecious – male and female flowers separate but on the same plant e.g. Zea mays (corn) (encourages outcrossing) Dioecious – male and female plants separate (must outcross)
Diploid
Refers to cells containing two sets of chromosomes; designated as 2n.
Diploid/sporophyte dominant
Species in which the diploid organism is the prevalent organism in the life cycle. Animals are an example.
dominant
dominant A term that describes the displayed trait in a heterozygote. dominant species A species that has a large effect in a community because of its high abundance or high biomass.
Double fertilization
n angiosperms, the process in which two different fertilization events occur, producing both a zygote and the first cell of a nutritive endosperm tissue.
Electron transport
A group of protein complexes and small organic molecules within the inner membranes of mitochondria and chloroplasts and the plasma membrane of prokaryotes. The components accept and donate electrons to each other in a linear manner and produce a H electrochemical gradient.
embryo
The early stages of development in a multicellular organism during which the organization of the organism is largely formed.
Endosperm
A nutritive tissue that increases the efficiency with which food is stored and used in the seeds of flowering plants. // - Endosperm (3n) – Rich in nutrients for developing embryo – In many dicots, food reserve of endosperm is restocked in cotyledons, so mature seed will lack endosperm // Fertilization of two polar nuclei -> endosperm (3n)
Ephedra
Division Gnetophyta Fig. 30.11 - 3 genera – Gnetum, Ephedra and Welwitchsia - Once thought to be a transition between Gymnosperms and Angiosperms - Now believed to be closely related to Conifers (recent molecular data) Characteristics of Gnetophytes - Leaves of Gnetum have net venation - Floral like strobilus - Vessels present in xylem - Double fertilization recently found in Ephedra and Gnetum Welwitschia
Ephemerals
Cool Temperate forests - Dominated by deciduous angiosperms Perennials common on forest floor - Spring ephemerals - grow and flower rapidly in spring before shaded out by trees
Epidermis
A layer of dermal tissue that helps protect a plant from damage. // Dermal tissue - Epidermis – single layer of tightly packed cells
Epiphyte
Epiphytes Depend on other plants for mechanical support – get up higher in canopy Broad-leafed tropical rainforest plants // Tropical rainforest - Greatest diversity of angiosperms - Adapted to low light (forest floor) - Epiphytes and lianas common – adaptation of growth form to compete with trees for light
Evolutionary innovation
Major evolutionary innovations of Angiosperms – Xylem – vessel elements in addition to tracheids found in conifers – Flowers - attract pollinators (Radiation of flower species accompanies by radiation in insect species) – Double fertilization
fern
Ferns - Most common of the seedless vascular plants - 12,000 species - Larger leaves – megaphylls (fronds) - Branching veins - Tip curled in early spring (fiddleheads) - Sporophyte dominant but haploid phase macroscopic - Produce spores in specialized sporangia usually on underside of leaf - Sporangia in clusters called sori (sorus singl.) - Sporangia may have an annulus – spore dispersal // Generalized life cycle – alternation of generation – haploid or diploid dominant. (Key examples mosses, ferns)
Fertilization
The union of two gametes, such as an egg cell with a sperm cell, to form a zygote. // - Fertilization of egg -> zygote -> embryo -> mature plant - Fertilization of two polar nuclei -> endosperm (3n)
Fibres
Fibers - Long slender and tapering in bundles (Rope, flax)
Fibrous roots
Fibrous roots are examples of adventitious roots, structures that are produced on the sur- faces of stems (and sometimes leaves) of both monocots and eudicots. Roots that develop at the bases of stem cuttings are
Fleshy fruit
There are a range of different types of fruits Fruit types - Simple – Fleshy e.g. apricot // Explain how seed dispersal may differ for fleshy fruits (e.g. apple, peach) from dry fruits (e.g. maple)
Floral mimicry
Bee Pollination with floral mimicry - Flower resembles female bee - Can produce female scents (pheromones) - Pseudo-copulation achieves pollen collection
Flower
A reproductive shoot; a short stem that produces reproductive organs instead of leaves.
Forensic plant anatomy
Anatomy – root growth, anatomy can determine disturbance and time of burial; plant cell types in victim stomach contents (sclerids, tracheids, vessel cells, silica bodies from grasses); wood fragments can be traced to furniture or forest locations
Fossil
Plant Fossils - Oldest known land plant fossils are microscopic ~476 mya – Sheets of waxy cuticle (protect against…?) – Spores with sporopollenin walls // Recognizable preserved remains of past life on Earth.
Fruit
A structure that develops from flower organs, encloses seeds, and fosters seed dispersal in the environment. 2. fruiting bodies The visible fungal reproductive structures that are composed of densely packed hyphae that typically grow out of the substrate.
Gametangium
Specialized structures produced by many land plants in which developing gametes are protected by a jacket of tissue.
Gamete
A haploid cell that is involved with sexual reproduction, such as a sperm or egg cell.
