Download PASS Review—Plants Name: All living organisms share the

PASS Review—Plants
Name:
All living organisms share the following characteristics: Obtain and use energy for food:
(autotrophs—make food through photosynthesis; heterotrophs—must find food); energy is released
from food through respiration; Respond to Stimuli: stimulus—change in surroundings that causes
a reaction (“cause”); response—the reaction (“effect”); Reproduce: asexual—one parent, offspring
identical; sexual—two parents—egg and sperm, offspring different; Grow and Develop: growth—
getting larger, development—getting more complex
Scientists name and classify organisms according to similarities in their structures. Taxonomy—the
study of how scientists classify organisms; Scientists use a series of levels to group organisms—the
more levels they share with each other, the more characteristics they have in common. Biggest to
smallest: Kingdom, phylum, class, order, family, genus, species (King Phillip came over for good
spaghetti). Kingdom—biggest group—5/6 kingdoms (Plants, Animals, Fungi, Protists, and
Monera (Bacteria—split into 2 kingdoms recently: Eubacteria and Archaebacteria); organisms placed
into kingdoms based on ability to make food and number of cells they have; Genus—first part of an
organisms scientific name; species—second part of scientific name; consists of organisms that can
breed and produce young of the same kind; Scientific name—made of genus and species; written in
italics or underlined; genus is capitalized and species is lower case. Example: Canis lupus.
Plants are classified according to specific structures. Vascular plants: true roots, stems, and leaves;
tubes to move water and food; xylem carries water, phloem carries food; some have a woody stem,
some have a herbaceous stem (soft and green). Nonvascular plants: no true roots, stems, or
leaves; no tubes to carry water and food—moves it from cell to cell; live in wet areas and are very
short; examples are mosses. Seed-producing plants vs spore producing plants: seeds—made by
cone bearing and flower bearing plants. Seeds have an embryo (baby plant), cotyledon (stored
food) and seed coat. Spores—much smaller than seeds; produced by mosses, ferns, and fungi.
Flowering plants vs. cone-bearing plants: flowering plants—seeds grow inside ovary, inside
flower. Flower becomes fruit containing seeds. Two kinds: monocots (one food storage area in seed;
petals in multiples of 3; parallel veins in leaves; scattered vascular structures in stem. Examples are
grass, corn, rice, lilies, and tulips) Dicots (two food storage areas in seed; petals in multiples of 4 or
5; branching veins; vascular structures arranged around edge of stem. Examples: roses, dandelions,
maple, and oak trees) Cone-bearing plants—most are evergreen with needle-like leaves; conifers
have seeds in cones; examples are pine, spruce, redwood, and cedar trees.
Flowering plants have special structures that function for defense, survival, and reproduction.
Defense: thorns, poisons, thigmotropism (leaves close when touched); Survival: Leaf: site of
photosynthesis, respiration, and transpiration; Stem: holds the plant up and can store food;
xylem and phloem pass through; Roots: anchor the plant and absorb water; root hairs increase
surface area and absorb water; two types of roots—fibrous (branching; ex: grass, corn, trees) and
tap (one main root; ex: carrot, dandelion, radish). Reproduction: Flowers: produce seeds; have
colors and scents to attract insects; stamen (male—anther produces pollen and filament is the
stalk) and pistil (female—stigma (sticky—pollen lands here), style (tube—pollen tube grows through
this after pollination) and ovary (has the ovules where eggs are produced). Ovule becomes the
seed; ovary becomes the fruit and protects the seeds.
All flowering plants have similar life cycles with distinct stages. Germination: the early growth stage
of a seed; roots grow down, stem grows up. Seeds may lay dormant after dispersal from parent, or
may germinate if the conditions are right. Plant development: seed grows into a mature plant;
Fertilization: when pollen transfers from stamen to pistil (pollination) and then enters the ovule in
the ovary, fertilization has occurred. Seed production: Once ovule is fertilized, it develops into seed,
and ovary develops into fruit.
Plants can reproduce sexually and asexually. Sexual reproduction: requires a sperm cell (in
pollen) and an egg cell (in ovule) to combine to produce a new organism; all flowering plants
reproduce sexually; Asexual reproduction: one parent; offspring are identical to parent; many plants
can grow new plants from their plant parts: tubers and bulbs—types of underground stems;
examples: potatoes, onions; runners—types of stems that run along the ground; examples:
strawberries, ivy, lawn grasses; stem cuttings—a new plant grows when a piece of stem is planted;
examples: sugar cane and pineapples; roots—some trees and bushes send up “suckers” or new
shoots from roots; leaves—houseplants like African violets can produce new plants from leaves
placed on top of soil
All plants perform certain processes that are necessary for their survival. Photosynthesis: process
by which plants make their own food, a simple sugar, for survival; chloroplasts, found in the cells of
the leaf, contain chlorophyll, which absorbs light energy; carbon dioxide gas enters stomata
(openings in leaf) and combines with water from roots to make sugar in leaves; oxygen is produced
and enters air through stomata; photosynthesis provides oxygen in the atmosphere. Respiration:
process where plants break down the food made during photosynthesis in order to use the energy
stored in the food; oxygen (from stomata) combines with sugar releasing energy. Carbon dioxide and
water are also formed. (sort of the opposite of photosynthesis.) Transpiration: the process of plants
losing water through their leaves through openings called stomata (“plant sweat”); Guard cells
control the opening and closing of the stomata; when stomata are closed, water cannot escape from
leaf
Plants respond to changes in their environments. Dormancy—a period of time when the growth or
activity of a plant or seed stops due to changes in temperature or water amount. Tropism—when
plants respond to changes in the environment by growing or moving their stems, roots, or leaves.
Phototropism: responding to light; gravitropism: gravity (also called geotropism); hydrotropism:
response to water; thigmotropism: response to touch
Fungi are a kingdom of organisms that do not make their own food. They grow in or on other living
things. They can harm and eventually kill a plant, and cause huge crop losses. Examples are grain
mold, corn smut, and wheat rust.