General Biology for Non-majors
Plants and People: Exam Study Guide
Chapter 1 – Introduction
• What makes something a plant?
o The combination of how it reproduces, its structure, and how it gets its nutrition and energy. Plants
are green because they contain chlorophyll. They make food/energy through the process of
photosynthesis. Plants don’t move; they have very rigid cell walls. Plants have
flowers/seeds/fruits, spores (ferns/mosses), or cones (conifers) as their mode of reproduction.
• Organisms are named according to the binomial system – genus and species.
o Ex. Homo sapiens
• Organisms are classified on the basis of their evolutionary/genetic relatedness.
• The kingdom is the highest (most all-inclusive) grouping of life.
o Kingdom, phylum, class, order, family, genus, species
• The five kingdoms of life are bacteria, animals, fungi, protists, and plants.
• Bacteria were the first organisms to evolve.
• Life first appeared on earth 3.5 billion years ago.
• Photosynthesis evolved 3 billion years ago.
• Multi-cellular organisms evolved 1.5 billion years ago.
• Green plants evolved 1 billion years ago.
• Fungi evolved about 1 billion years ago.
• Animals are more closely related to fungi than they are to plants.
Chapter 2 – The Special Features of Plant Cells
• All living things are composed of cells.
• The cell is the basic unit of life.
o Each cell is surrounded by a cell membrane. (Plant cells also have cell walls.)
o Each cell contains a nucleus and cytoplasm.
• Plant cells have all the components found in animal cells but in addition have a cell wall on the outside of
the cell membrane and chloroplasts in the cytoplasm.
• The chloroplasts are the site of photosynthesis.
• The cell wall provides the plant with structural strength and rigidity. • Photosynthesis is the reaction that makes life possible. It brings carbon into a form that can be used to
make the molecules of our bodies and converts sunlight into an energy form that organisms can use.
o CO 2 H 02---Light---> Sugars + 02(Photosynthesis)
• Animals get their energy by digesting plantmaterials. They break these materials down to CO2 and water
through the process of respiration, aka breathing.
o Sugars + O 2 CO +2H 0 2 Energy (Respiration)
• The carbon cycle
o Carbon enters the atmosphere as carbon dioxide from respiration and combustion (burning).
o Carbon dioxide is absorbed by plants for photosynthesis. The plants produce oxygen that humans
need to breathe and serve as a source of food for animals.
o After animals feed on the plants, they eventually exhale carbon dioxide through the process of
o The animals and plants eventually die, and the carbon that was in their bodies is returned to the
atmosphere as carbon dioxide when they decompose.
o When decomposition is inhibited, the dead plants and animals may eventually turn into fossil
fuels, which, when burned, also release carbon dioxide into the atmosphere.
• Xylem and phloem are the “plumbing” of plants.
o Xylem transports water from the roots to the leaves, and phloem transports sugars from the leaves
to all the parts of the plant that are not photosynthetic – roots, interior parts of the stem, fruits,
• The movement of water from the roots to the leaves and then out to the atmosphere is called transpiration.
• Because plants lose lots of water through transpiration, they must have a way to control the loss.
o Plants restrict water loss by having a waxy layer on the surface of the leaf and allowing CO2
uptake and water release only through special pores in the leaf surface called stomates.
Each stomate is surrounded by two guard cells that can swell or shrink to open the pore.
When the soil by the plant has lots of water, the guard cells swell and open the stomates,
allowing CO2 into the leaf and water to escape. When the soil is dry, the guard cells
shrink, closing the stomate. When this happens, the plant loses much less water, but it
cannot take in CO2, so photosynthesis stops.
• Cellulose is a molecule in the cell wall that provides plants with most of their strength. It is composed of
chains of sugars, assembled into rods, which are highly resistant to degradation. It has the relative strength
of steel on the plant’s scale.
Chapter 3 – How PlantsAre Put Together Know where the shoot, stem, leaf petiole, shoot
tip, lateral bud root, and root tips are.
• Growth in length is due to production of new cells in the shoot and root tips.
• Plants that live more than one year (perennials) grown in width by means of cell divisions in the body
of the stem and root. These perennials grow mainly in width after they have reached a certain height.
• The shoot tip makes the cells of the shoot as well as those of leaves, lateral buds, and flowers.
• A flower is a modified shoot tip. When flowering starts, the shoot tip makes a flower
instead of a lateral bud, and growth stops.
• The stamen is the male part of the plant, and the pistil is the female part.
• The stamen contains the anther and the filament (stalk), while the pistil contains the
ovary, stigma, and style.
o Inside the ovary are one or more ovules, and in each ovule is
• The pollen grains, which contain sperm, form in the anther. Pollen is carried from the anther to the
stigma of the pistil. The pollen grain germinates to form a tube, which grows down the stigma and
style into the ovary and then into the ovule. It then fuses with the egg cell, fertilizing it.
• PLANT REPRODUCTION HAVE TWO PARTS. POLLINATIO N IS THE TRANSFER OF POLLEN
FROM THE ANTHER TO THE STIGMA. FERTILIZATION IS THE FUSION OF THE SPERM
AND EGG TO MAKE THE NEXT PLANT GENERATION.
• FLOWERSARE FOR POLLINATIONAND FERTILIZATION. FRUITS ARE FOR SEED
DISPERSAL. • After fertilization, the ovule grows and develops into the seed, which contains a plant embryo.
Simultaneously, the ovary enlarges and develops into fruit.
• The endosperm provides the embryo with nutrients.
• The cotyledons are modified leaves that also store nutrients for the embryo.
Chapter 4 – Pollination and Seed Dispersal
• The function of the flower is to ensure that pollination occurs.
• Wind-pollinated flowers have small petals or no petals at all, lots of pollen, and large stigmas.
• Animal-pollinated flowers produce attractants (colorful petals and scents) and rewards (sugary nectar and
• Flowers that are pollinated by bees are blue or yellow in color and have sweet odors. They also have broad
open surfaces or petals large enough so that the bee can grab on. Butterfly-pollinated flowers are similar to
those pollinated by bees. Bees and butterflies are generalists, meaning that they visit the flowers of many
• Plants that are pollinated by hummingbirds usually have odorless red flowers, as hummingbirds have a
poor sense of smell and produce lots of nectar.
• Flowers pollinated by bats and nocturnal moths are open at night, are white or dull-colored, and have heavy
musty or fruity odors. Bats feed on both pollen and nectar, but moths only use the nectar.
• Flowers pollinated by flies are reddish brown and release the odor of rotting meat.
• Only orchids are pollinated by wasps. The orchid flower resembles the abdomen of a female wasp, and the
petals emit the same odor that the female wasp uses to attract her mate. The male wasps attempt to copulate
with the flower and pick up pollen in the process.
• Many plants frequently self-pollinate. However, self-pollination results in genetically uniform offspring.
• Flowers are designed to promote cross pollination, which greatly increases genetic variability.
• The function of fruits is to promote seed dispersal. • Fleshy fruits are intended to be eaten by animals so that the seeds will be dispersed with the animal’s feces.
Dry fruits may be adapted for dispersal by animals (clinging to fur or being collected like acorns) or by
wind or water.
Chapter 5 – TheAlgae and Evolution of Land Plants
• Algae are simple, photosynthetic, aquatic organisms.
• Plankton are organisms that live suspended in water.
• Phytoplankton are photosynthetic plankton.
• Phytoplankton are greatly important in the ocean. They are at the bottom of the food chain and therefore the