Plants Lab Practical 2

Simple fruit

Formed from a single pistil

Dry fruit

Pericarp is dry, tough, or thick

Indehiscent

Not opening at maturity

Achene

Seed attached at one point inside the pericarp; examples: sunflower, strawberry

Caryopsis (grain)

Seed fused to the pericarp; examples: wheat, corn, rice

Samara

A winged pericarp; examples: ash and elm

Nut

Very hard stony pericarp; examples: acorn (oak), chestnut

Schizocarp

Split fruit with ovaries in pairs; examples: carrot, dill, parsley, maple

Dehiscent

Fruit splitting open at maturity

Follicle

Splits open along one suture; examples: magnolia, milkweed

Legume

Splits open along one suture; examples: bean, pea, redbud tree

Capsule

Splits open along more than two sutures; examples: tulip, iris, okra, poppy

Silique

Seeds formed on a partition between halves of an ovary; examples: mustard, radish

Fleshy fruit

Pericarp usually thick and juicy

Berry

One to many seeds formed in a superior ovary that is fleshy throughout; examples: grape, tomato, avocado, kiwi, eggplant

Hesperidium

Outer layer covered with leathery skin containing oils, inside fleshy fruit with juice sacs; examples: orange, lime, grapefruit

Pepo

Many seeds formed in an inferior ovary, thick rind, no oils; examples: cucumber, squash, watermelon, pumpkin

Drupe

One-seeded fruit with fleshy outer pericarp and hard stony endocarp; examples: cherry, peach, walnut, pecan, coconut

Pome

Inferior ovary with fleshy part derived from the receptacle; examples: quince, apple, pear

Aggregate fruit

Derived from several pistils on the same flower

Multiple fruit

Develops from many flowers whose fruits fuse into one structure; examples: hedge apples, pineapple, mulberries

Hydrophytes

Lacking a cuticle or stomata, adapted to water

Xerophytes

Plants with thick cuticle, adapted to arid climates

Tendrils

Modified leaves that increase plant stability; example: pea plant

Sensitive plants

Plants that respond to electrical and chemical signals; example: mimosa

Carnivorous plant

Plant modified to attract and digest insects; example: Venus flytrap

Other modified leaves

Modified leaves such as thorns, spines, prickles, onion bulbs

Cotyledon

Embryonic leaves that emerge from a seed

Apex

Tip of the leaf

Margin

Edge of the leaf

Veins

Network of vascular tissues in a leaf

Midrib

Main vascular tissue running through the center of a leaf

Base

Portion of a leaf attaching to the petiole/stem

Petiole

The stalk that joins a leaf to a stem

Stipule

Small appendage at the base of a petiole

Opposite

Two leaves per node

Alternate

One leaf per node

Whorled

Rings of three or more leaflets

Rosette

Leaflets in tight circular rings

Simple leaf

A leaf with an undivided blade; example: maple

Compound leaf

A leaf whose blade is divided forming leaflets

Leaflet

Leaf-like part of a compound leaf

Rachis

Extension of the petiole in a compound leaf that bears individual leaflets

Petiolule

Stalk attaching leaflets to the rachis

Palmately compound leaf

A compound leaf with leaflets radiating outward from the end of the petiole; example: buckeye

Pinnately compound leaf

A compound leaf with leaflets arranged along the middle vein; example: black locust

Bipinnately compound leaf

Twice divided leaf with secondary and tertiary leaflets; example: mimosa

Parallel venation

Veins run in straight lines across the leaf without converging; typical of monocots

Reticulate venation

Net-like veins extending along the midrib; typical of dicots

Palmate venation

Veins radiate along the leaf from the petiole

Pinnate venation

Veins extend from the midrib to the leaf edges

Dichotomous venation

Veins fork into two equal branches toward the margin; example: ginkgo

Epidermis

Outer covering of roots, stems, and leaves; provides protection and allows transpiration

Cuticle

Protective waxy layer covering the leaf epidermis that prevents water loss

Stomata

Opening that allows a plant to take up carbon dioxide and release oxygen and water vapor

Guard cells

Paired cells flanking a stoma that regulate its opening and closing

Dicot guard cells

Kidney bean shaped guard cells

Monocot guard cells

Dumbbell shaped guard cells

Dicot leaf mesophyll

Made up of palisade and spongy mesophyll

Monocot leaf mesophyll

Contains only spongy mesophyll

Pistil

Contains the female parts of a flower

Stamen

Contains the male parts of a flower

Complete flower

Flower with sepals, petals, stamens, and pistil

Incomplete flower

Flower with no sepals

Staminate flower

Flower with male structures only

Pistillate flower

Flower with female structures only

Monocots

Plant group whose flower parts occur in 3s

Dicots

Plant group whose flower parts occur in 4s or 5s

Epigynous

Inferior ovary

Perigynous

Superior ovary

Hypogynous

Superior ovary

Fruit

The mature ovary or ovaries of one or more flowers

Seed

A fertilized (mature) ovule containing the plant embryo

Pericarp

Part of a fruit formed from the wall of the ripened ovary

Endosperm

Nutritive tissue for the developing embryo

Aggregate fruit

Fruit developing from several pistils on the same flower

Multiple fruit

Fruit developing from multiple flowers whose fruits fuse into one structure

Inferior ovary

Ovary located below or inside floral parts

Superior ovary

Ovary located above or on the same level as floral parts

Ovule

Eventually develops into seeds

Calyx

Sepals collectively referred to as the calyx

Corolla

Petals collectively referred to as the corolla

Micropyle

Small opening by which the pollen tube reaches the ovule

Mitosis

Cell division process going from haploid to diploid

Meiosis

Cell division process going from diploid to haploid

Stipule function

Helps protect young, new growth

Double fertilization

When two sperm are involved in fertilization