APBIO5.StudyGuideCheckList - Biodiversity
The following checklists provide main concepts to review. Question types on the exam
for these topics can test knowledge and comprehension, synthesis and evaluation, and
scenario analysis.
Plant Diversity
Chapter 29 – How Plants Colonized Land
Chapter 30 – The Evolution of Seed Plants
Chapter 38 – Angiosperm Reproduction
Plants are thought to have evolved from green algae more than 500 million years
ago.
Plants drive/fuel the biodiversity of other lifeforms on land, in part because they are
primary producers and also because they contribute to gas exchange (oxygen and
carbon dioxide)
Evidence for the evolution of land plants from the green algae group charophytes:
They produce cellulose for cell walls
The peroxisomes of both groups have enzymes that reduce the effects of
photorespiration
The structure of their sperm is similar
They produce cell plates during cell division
Genetic evidence including analysis of nuclear and chloroplast genes show the
close relation
Phragmoplasts are directly involved with construction of the cell plate
Mosses and other nonvascular plants have life cycles dominated by gametophytes
Bryophytes include mosses, liverworts, and hornworts
Bryophytes are nonvascular, meaning they lack xylem and phloem
Instead of true roots, bryophytes have rhizoids
The life cycle of mosses includes antheridia and archegonia that are produced by
gametophytes
Meiosis produces spores in sporophytes, mitosis produces gametes in gametophytes
Factors that permitted early plants to colonize land include:
The relative number of potential predators
The relative number of competitors
The relative availability of symbiotic partners
Characteristics of ferns include:
Flagellated sperm
Xylem with tracheids
Separate gametophyte and sporophyte generations with the sporophyte
dominant and independence of one generation from the other
No seeds
Seed-producing plants include pollen. This is a key distinction between
gymnosperms and ferns
A pollen grain is a male gametophyte that has a waterproof coating, allowing for
transfer by the wind.
APBIO5.StudyGuideCheckList - Biodiversity
Double fertilization means that one sperm is needed to fertilize the egg, and a second
sperm is needed to fertilize the polar nuclei
Key adaptations for life on land that are unique to seed plants include:
Reduced gametophytes that are microscopic and dependent on the
sporophyte for food and protection
Heterospory, or the production of two types of spores (megaspores, or
female gametophytes/eggs and microspores, or male gametophytes/sperm)
Ovules and the production of eggs
Pollen and the production of sperm
Seeds. Seeds have advantages over spores – multicellular; several layers of
protective tissue to safeguard the embryo; a supply of stored energy
Gymnosperms include conifers such as pines, spruces, firs, and redwoods
Angiosperms have reproductive structures called flowers and fruits
Angiosperms account for approx. 90% of all plant species today
Fruits contribute to success of angiosperms by facilitating seed dispersal
Ovules develop into seeds, and mature ovaries develop into fruits
Key Questions and Concepts to Review
Alternation of generations
Review life cycle diagrams for mosses, ferns, pines, and angiosperms
Be able to identify floral structures and their functions: sepal, petal, stamen, carpel,
filament, anther, stigma, style, ovary, ovule
Distinguish between monocots and dicots
Describe the threat that human population growth poses to plant diversity
What are advantages for having vascular tissue? Roots and leaves? Seeds?
Study the multiple choice samples at the end of each chapter (review answers in
appendix A)
APBIO5.StudyGuideCheckList - Biodiversity
Animal Diversity
Chapter 32 – An Overview of Animal Diversity
Chapter 40 – Basic Principles of Animal Form and Function
Animals have the following characteristics:
They are multicellular heterotrophs
They ingest food
Most have muscle and nervous tissue
Most reproduce sexually, with a flagellated sperm and a large egg uniting to
form a diploid zygote
Development – some have a larval stage, distinct from the adult stage, and the need
to undergo metamorphosis
Animals share Hox genes
Body plans –
Sponges have no symmetry
Radial symmetry vs bilateral symmetry
Cephalization – the concentration of sensory equipment at one end (the
anterior, or head end) of the organism
Acoelomates, such as flatworms, have no cavities between alimentary canal
and the outer wall of their bodies
Pseudocoelomates, triploblastic animals (with three tissue layers) have a
cavity formed from the mesoderm and endoderm
Coelomates possess a true coelom, or body cavity filled with fluid that
separates digestive tract from the outer body wall. The body cavity forms
from the mesoderm only
Functions of the body cavity:
It cushions suspended organs
It acts as a hydrostatic skeleton
It enables internal organs to grow and move independently
The last common ancestor of all animals was probably a flagellated protest
(choanoflagellates)
Differences between Protostomes and Deuterostomes (refer to 32.3)
Cleavage (at eight-cell stage, spiral or radial)
Coelom formation
Fate of the blastopore (mouth or anus)
The Cambrian explosion is a prime example of adaptive radiation
Evolutionary history, supported by fossil evidence, places the following from
earliest to most recent events:
Cambrian explosion occurs
Vertebrates become top predators in the seas
Protostomes invade terrestrial environments
Deuterostomes invade terrestrial environments
Organization of cell types, from tissues to organs to organ systems
Systems that specialize in control and coordination: endocrine system and nervous
system. Roles of hormones and neurons, and how signals are sent.
APBIO5.StudyGuideCheckList - Biodiversity
Homeostasis – animals maintain a relatively constant internal environment
Control systems function by having a set point, sensors to detect stimulus above or
below that point, and a physiological response that helps return the body to its set
point
Negative vs. positive feedback systems
Thermoregulation – changes including panting, sweating, shivering, or behaviors
such as burrowing or sunning
Endotherms vs ectotherms
Means for heat transfer
Metabolic rate, the total amount of energy an animal uses in a unit of time, and how
it relates to body size
Torpor involves a decrease in metabolic rate, conserving energy during
environmental extremes.
Key Questions and Concepts to Review
Characteristics of animals
Stages of animal development
How to sort animal phyla based on symmetry, development of body cavity, and the
blastopore
How can one distinguish between a diploblastic embryo and a triploblastic embryo
based on gastrulation?
Study the multiple choice samples at the end of each chapter (review answers in
appendix A)