Leaves Chapter 7 (Week 3 Lecture 4) Flashcards
True or False: All leaves originate as primordia in buds.
True
Leaves of flowering plants associated with ______ ______ and have ______ buds at base.
Leaf gaps, axillary
Stalk of leaf is also known as ______.
Petiole
True or False: Leaves sessile if lacking petiole.
True
______ are at the base of the petiole.
Stipules
The flattened blade is also known as the ______.
Lamina
What are simple leaves?
Leaves with a single blade
Compound leaves ar leaves with their blades divided into ______.
Leaflets
What is the difference between pinnately (bipinnately) compound leaves and palmately compound leaves?
Pinnately leaves - Leaflets in pairs along rachis (petiole)
Palmately compound leaves - All leaflets attached at same point at end of petiole
Trapping and storing of energy in sugar molecules that are constructed from water and carbon dioxide is known as?
Photosynthesis
What are stomata?
Tiny pores on lower surfaces of leaves
What is the function of stomata?
Allow carbon dioxide to enter and oxygen to diffuse out
______ cells control water loss by opening (swell) or closing (contract) pore of ______ apparatus.
Guard, stomatal
Why do leaves fall off?
Wastes from metabolic processes accumulate in leaves and are disposed of when leaves are shed.
______ occurs when water evaporates from leaf surface.
Transpiration
______ is when root pressure forces water out hydathodes at tips of leaf veins in some plants.
Guttation
What is phyllotaxy?
Arrangement of leaves on stem
______ is the arrangement of veins in a leaf or leaflet blade .
Venation
True or False: Palmately veined leaves have a main mid-vein included within enlarged midrib.
False, palmately veined leaves have several primary veins fan out from base of blade
True or False: Monocots have netted or reticulate ventilation
False, dicots have netted or reticulate venation while monocots have parallel venation
______ venation is when veins fork evenly and progressively from base of blade.
Dichotomous
Where does most photosynthesis take place?
Takes place in the mesophyll between the two epidermal layers
Most of the leafs chloroplasts are found in the ______ mesophyll.
Palisade
What is spongy mesophyll?
Loosely arranged parenchyma cells with abundant air spaces
______ consist of xylem and phloem tissues surrounded by bundle sheath of thicker-walled parenchyma
Veins
What do monocots have that dicots do not in there mesophyll and veins?
Bulliform cells
What are bulliform cells?
Causes leaf to fold or roll, reducing transpiration
______ leaves have fewer defined mesophyll layers and fewer chloroplasts and have fewer hairs.
Shade
Leaves of arid region s reduce loss of water by what four characteristics?
Thick, leathery leaves
Fewer stomata or sunken stomata
Succulent, water-retaining leaves, or no leaves
Dense, hairy coverings
True or False: Leaves of aquatic areas have less xylem and phloem.
True
______ are modified leaves that curl around more rigid objects, helping the plant to climb or to support weak stems found in garden peas.
Tendrils
______ are modified leaves that reduce leaf surface and water loss, and protect from herbivory found in cacti.
Spines
______ are modified stems arising in the axils of leaves of woody plants.
Thorns
______ are outgrowths from epidermis or cortex.
Prickles
Storage leaves have ______ cells with large vacuoles.
Parenchyma
What is the function of flower pot leaves?
Leaves develop into urn-like pouches that become home of ant colonies
______ leaves allow light into leaf, while buried leaves keep plant from drying out.
Window
Walking fern and air plant have ______ leaves.
Reproductive
Poinsettia and Clary’s sage are known as ______ leaves or ______.
Floral, bracts
True or False: Insect-trapping leaves grow in swampy areas and bogs where nitrogen and other elements are deficient in soil.
True
Pitcher plants, sundews and venus fly-traps are examples of what type of specialized leaves?
Insect-trapping
What type of insect-trapping leaves can be found in water?
Bladderworts
In fall, ______ break down and other colors are revealed.
chlorophylls
What type of plant drops leaves seasonally?
Deciduous
______ is the process by which leaves are shed
Abscission
How do leaves fall off during abscission (separation layer).
Pectins in middle lamella of cells are broken down by enzymes
