Ch. 23-26 “Introduction to

Plants”

I. Adaptations of PlantsA. Today’s plants probably evolved from green

algae.B. To survive on land, plants had to be able to do

three things:1. Absorb nutrients2. Prevent water loss

a. Cuticle-waxy protective covering of a plantb. Stomata-pores in the leaves that

allow for the exchange of gases.c. Guard cells-specialized cells that

regulate the opening and closing of the stomata.

3. Reproduce on land a. Pollen-contains the sperm and allows it to be carried by wind or animals instead of water.

Cross-section of leaf

II. Characteristics of PlantsA. Cell walls made of celluloseB. Multicellular and eukaryoticC. Autotrophic – produce own food through

photosynthesisD. contain chloroplasts – structure that contain

green pigment chlorophyll

III. Kinds of PlantsA. Nonvascular Plants

1. Do not have a vascular system.2. Need water for sexual reproduction.3. Examples include mosses, liverworts, and

hornworts.

B. Seedless Vascular Plants

1. Have a vascular system - internal system of interconnected tubes and vessels for transporting food and water.

a. phloem-transports food.b. xylem-transports water.

2. Have spores with thick walls to prevent drying out

3. Examples include ferns, club mosses, horsetails

C. Gymnosperms1. Seed plants that produce seeds in cones.2. Have a vascular system.3. Examples include conifers, cycads, and

ginkgos.

D. Angiosperms (flowering plants)

1. Produce flowers -reproductive structure that produces fruits and seeds.

a. Attract birds, animals, and insects to carry pollen.b. Reproductive parts called stamen (male part produces pollen) and pistil (female part produces ovules)

2. Produce seeds enclosed within a structure called a fruit.a. provide food, protect the seed, and help disperse

the seed.b. Seeds contain a supply of stored food called the

endosperm.

3. Classified into two groups:a. Monocots

-Produce seeds with only 1 seed leaf (cotyledon)-Flower parts in multiples of 3’s-leaves have parallel veins-crocus, corn, grass

b. Dicots-produce seeds with 2 seed leaves-flower parts in multiples of 4’s or 5’s-leaves with branching veins-roses, apples, beans

IV. Plants in Our LivesA. All plant parts-roots, stems, leaves, flowers,

and fruit provide food.B. Wood for paper, lumber and fuelC. MedicinesD. Plant fibers make paper, cloth, and rope

The PLANT CellA – Vacuole – holds water

B – Cell wall – protection and support

C – Endoplasmic Reticulum – transport proteins

D – Nucleus – Control cell activities, Hold DNA

E – Mitochondria – Make energy into usable ATP

F – Chloroplasts – Convert CO2 into C6H12O6

G – Golgi Bodies – packages and distributes protein