SECRETORY STRUCTURES

TWO TYPES OF SECRETORY STRUCTURES

1. EXTERNAL

2. INTERNAL

EXTERNAL SECRETORY STRUCTURES

1. NECTARIES

 

SECRETE NECTAR TO ATTRACT ANIMALS AND INSECTS

a. FLORAL NECTARIES

1. ASSOCIATED WITH FLOWERS

2. ATTRACT POLLINATORS

b. EXTRAFLORAL NECTARIES

1. OCCUR ON VEGETATIVE PARTS OF PLANTS

2. ATTRACT ANIMALS TO DEFEND PLANT (ie.

ants eat nectar and keep flies from

laying eggs on plant)

2. HYDATHODES

a. SECRETE WATER VIA GUTTATION

b. ARE LOOSE ARRANGEMENTS OF PARENCHYMA CELLS

c. FOUND AT VEIN ENDINGS

d. EXANPLE - "DEW" ON PLANTS IN THE MORNING

3. DIGESTIVE GLANDS

 

a. FOUND ON CARNIVEROUS PLANTS

b. DIGEST INSECTS THAT GET CAUGHT

4. SALT GLANDS

a. REMOVE EXCESS SALT FROM PLANTS

b. FOUND IN PLANTS GROWING IN A SALINE ENVIRONMENT

 

INTERNAL SECRETORY STRUCTURES

1. SECRETORY CELLS

a. LARGE CELLS

b. CONTAIN SUBSSTANCES SUCH AS

1. OILS

2. TANNINS

3. RESINS

4. MUCILAGE

5. CRYSTALS

a. FUNCTION TO PRODUCE AND STORE CHEMICALS TO DETER

FORAGING ANIMALS

b. PRODUCTS USED BY MAN AS FOODS

1. PEANUT OIL

2. PALM OIL

3. CLOVE OIL

4. SAFFLOWER OIL

 

3. CANALS, DUCTS, AND CAVITIES

a. TRANSPORT RESINS AND OILS WITHIN THE PLANT

4. LATICIFERS

a. SECRETORY STRUCTURES CONTAINING LATEX (LATEX

IS CYTOPLASM CONTAINING CARBOHYDRATES, OILS,

ALKALOIDS, ORGANIC ACIDS, ENZYMES, RUBBER)

b. LATEX IS WHITE, OR COLORLESS

c. HAVE ONLY A PRIMARY CELL WALL

d. DETERS GRAZING ANIMALS

e. HUMAN USES

1. OPIUM, MORPHINE AND CODEINE FROM POPPIES

2. RUBBER FROM RUBBER PLANTS