Biological Foundations 112, Lecture 34


Dicots

Chapter 27
Five Kingdoms-5 12:24-16:33


I.   Class Dicotyledonae

     A.   Characteristics

            1.   Flower parts in 4s or 5s or multiples of 4s or 5s

            2.   Leaves with net veins

            3.   Two cotyledons per seed

            4.   Stems with vascular bundles in a ring

            5.   Roots, in primary growth, contain a vascular cylinder with two to five protoxylem      
                  poles

     B.   The families listed below are some of the more common families of California

II. Dicot Families

     A.   Family Brassicaceae - mustard family

           1.   Grows all over Napa Valley and transforms the valley into a mass of yellow in the      
                  spring

           2.   Four petals and four sepals arranged in the shape of a cross

           3.   Stamens six, four of them long and two of them short

           4.   Many important food plants in this group:

                 a.   Cabbage

                 b.   Radish

                 c.   Turnip

                 d.   Broccoli

           5.  Herbs

     B.   Family Fagaceae - oak family

            1.   Shrubs to trees that are monoecious

            2.   Simple leaves

            3.   Inflorescence always a catkin

            4.   Fruit is either an acorn with a basal cupule or a spiny bur enclosing 3 nutlets

            5.   An important lumber tree:

                  a.   A hardwood tree used for furniture, cabinets, and wine barrels

                  b.   Tannic acid was obtained from the bark of the Tan Oaks for use in the tanning of
                        leather.  Now tannic acid is manufactured synthetically for the same purpose.

     C.   Family Rosaceae - rose family

            1.   Ovary perigynous

            2.   Contains a hypanthium that is either separate from the ovary or that is adnate to the  
                  ovary

            3.   Stamens 10 to many, attached to the hypanthium

            4.   Many food plants and ornamentals in this group

                  a.   Cherries

                  b.   Peaches

                  c.   Apples

                  d.   Pears

                  e.   Apricots

                  f.   Blackberries

            5.   Herbs, shrubs, vines, trees

     D.   Family Fabaceae - pea family

            1.   Second largest dicot family in California

            2.   Herbs, vines, shrubs, trees

            3.   Flowers usually irregular in typical pea fashion with 5 petals

                  a.   Standard or banner - 1 petal

                  b.   Keel - 2 fused petals

                  c.   Wings - 2 separate petals

           4.   Stamens usually 10 and united by their filaments

           5.   Ovary superior

           6.   Fruit a pod or legume

           7.   Many ornamentals and food plants

                 a.   Peas

                 b.   Beans

                 c.   Sweetpeas

                 d.   Lentils

                 e.   Peanuts

     E.   Family Apiaceae - carrot family

           1.   Aromatic herbs

           2.   Compound alternate or basal leaves

           3.   Ovary inferior

           4.   Flower parts in 5s

           5.   Inflorescence an umbel

           6.   The two styles of the ovary are each standing on a stylopodium atop the ovary

           7.   Contains a number of food plants and ornamentals

                 a.   Anise

                 b.   Dill

                 c.   Carrots

     F.   Family Lamiaceae - mint family

           1.   Aromatic herbs and shrubs

           2.   Opposite or whorled leaves

           3.   Square stems

           4.   Flowers borne in the leaf axils or in terminal heads

           5.   Flowers are irregular

                 a.   Petals united into a two-lipped corolla

                 b.   Lower lip has three corolla lobes - the landing platform for pollinators

                 c.   Upper lip has two corolla lobes

           6.   Style arises from the center of a deeply lobed ovary

           7.   Common plants in this group:

                 a.   Sage

                 b.   Peppermint

                 c.   Hoarhound

                 d.   Catnip

     G.   Family Scrophulariaceae - figwort family

            1.   Herbs and shrubs

            2.   Contains snapdragon-like flowers

            3.   Flowers irregular and two-lipped (like the flowers in the mint family)

            4.   Style arises from the center of a non-lobed ovary (the mint flower has a deeply lobed
                  ovary)

            5.   Some of the common wild flowers of California:

                  a.   Monkey flowers

                  b.   Foxgloves

                  c.   Indian paintbrushes

     H.   Family Asteraceae - sunflower family

            1.   Herbs and shrubs

            2.   Typical composite flowers studied earlier in this course

            3.   Largest family in California


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