Final review Flashcards
Cell walls are made of
cellulose
Cellulose is a polymer of
glucose (sugar)
Define rhizome
rootlike stem, stem which shoots out roots from its nodes
The rhizome (underground stem) is useful for
water absorption
The xylem is
Water-conducting tissue (thick-walled)
Plants hold in water by having a
waxy skin
Stomata are
pores, occuring in plant stems and leaves, used to control water loss and gaseous exchange through the cuticle
The phloem is
Nutrient-conducting tissue (thin-walled)
To grow tall, plants need
lignified tubes (lignin is commonly derived from wood)
Define cutin
a waxy polymer used to protect spores
Water-conducting, soda straw-like tubes
xylem
An early land plant
Rhynia
Body cell division
mitosis
Sex cell division
meiosis
Define gametes
sex cells (e.g. eggs and sperm)
Haploid sperm and eggs unite to produce
diploid zygote
In plants, spores are produced by a process called
meiosis
A sporophyte is a
diploid spore-producing plant
Haploid spores germinate and divide by
mitosis
Germination is
the process by which plants, fungus and bacteria emerge from seeds and spores, and begin growth.
A gametophyte is a
haploid gamete-producing plant
Haploid eggs and sperm are made by a process called
mitosis
A trilete mark is a
“Y”-shaped mark on spores
Gemetophyte is
the portion of the plant life cycle producing sex cells (gametes)
Advantages of life in water
1) . Water provides a supporting protective medium that contains dissolved nutrients ad gases
2) . Water is less subjective to extremes of temperatures than air
3) . Water serves as a medium for motile phases of the life cycle
Disadvantages of life on land
1) . Subjective to lack of water (water stress)
2) . Greater seasonal and diurnal temperature change
3) . Susceptible to fluctuations in UV radiation
Define subaerial
Existing, occurring, or formed in the open air or on the Earth’s surface, not than underwater or undergroud
What does it mean for the xylem to be lignified?
Thickened and strengthened by lignin, a type of organic compound
The sporophyte is
the spore-producing portion of the plant life cycle
What constitutes the woody tissue
xylem
Spores are produced in
sporangia (“spore sacs”)
In higher plants, spores are always produced by
meiosis
Spores are haploid. This means that
they have one-half of the set of chromosomes that occurs in the body cells of the “adult” sporophyte plant
Trilete marks are a result of
spores being produced in groups of four by meiosis.
Haploid spores divide by
mitosis
Haploid spores divide by mitosis to produce
small gamete-producing plants (the gametophytes)
Because higher plant spores are haploid, and because the gametophyte is produced via mitotic growth, the gametophyte generation is
haploid
Fusion of the haploid gametes is called
syngamy
Gametes are units of
sexual reproduction
Spores are units of
asexual reproduction
Syngamy produces a
diploid zygote
The zygote produced via syngamy grows via
mitosis
As the zygote grows, it produces an embryo and, ultimately,
the diploid spore-producing (sporophyte) generation
Unlike Cooksonia (410 Ma), Rhynia (400 Ma) had both
a phloem for movement of nutrients as well as a xylem for water transport and supporting body cells (cortex).
The earliest land plant was
Cooksonia
The first true vascular terrestrial plant was
Rhynia
The earliest land plants (Cooksonia, Rhynia) are classified as
Rhyniophytina
Cooksonia, Aglaophyton and Rhynia did not have any
leaves
Zosterophyllum had leaves in the form of
small scale-like appendages to the stem
Sawdonia is part of the group
Zosterophyllophytina (390 Ma)
Microphylls are
“small” leaves
The Rhyniophytina had a stem that was
naked (no leaves)
The Zosterophyllophytina had a stem that had
spines (no ldaves)
The Lycophytina had a stem that had
microphylls (small leaves with central mid-vein)
The earliest plant with true leaves was the
asteroxylon (earliest lycophyte)
The xylem of asteroxylon was in the shape of
a star (asteroxylon = “star-wood”)
The lycophytina had spore sacs on
the upper surface of leaves
The leaves of Lycophytina were arranged
spirally
The Lepidodendron (320 Ma), grouped as Lycophytina, was a
giant scale tree with spore cones and spirally arranged leaf bases
Give two examples of Rhyniophytina
Cooksonia and Rhynia
Give an example of a Zosterophyllophytina
Sawdonia
Give two examples of Lycophytina
Asteroxylon and Lepidodendron
What are two characteristics of Rhyniophytina?
Naked stems, no leaves
What are two characteristics of Zosterophyllophytina?
Spines on stems but no leaves
What is one characteristic of the Lycophytina?
Microphylls (“small leaves”) with central mid-vein
What is the earliest Lycophyte?
Asteroxylon
Stigmaria are
the roots of Lepidodendrons
Distinguish between nodes and internodes of Horsetails (Equisetum)
Nodes are spirals from which branches protrude, internodes are the spaces between the spirals
Horsetails are part of which group?
Sphenophytina
Give one example of a Sphenophyte
Calamites (ancient horsetail)
Define megaphylls
“Big leaves”
The spore sacs of modern fern leaves are located at
the leaf margin (leaf end)
The earliest seed plants were
seed ferns
The “missing link” between spore and seed plants were
seed ferns, which had leaves like ferns but seeds, not spores.
What is considered to be the link from spore plants (ferns) to all later seed plants?
Seed ferns (regular ferns reproduce using spores)!
Name 2 things that ferns lack
Flowers and seeds (ferns reproduce using spores)
Who first noted the fit of South America and Africa?
Francis Bacon (1620)
Who formally proposed continental drift (movement of Earth’s continents relative to each other)?
Alfred Wegener (1922)
Dicot leaves are those with
branching veins.
Monocot leaves are those with
parallel veins (e.g. corn, palms).
The epidermis of early land plants is their
waxy skin.
Diploid body cells divide by
mitosis (keyword: body cells)
A diploid spore-producing plant is called a
sporophyte.
Haploid eggs and sperm in plants are produced by a process called
mitosis.
Trilete marks are produced on which surface of s spore?
Inner surface
To reproduce, spores require
water.
Arrange the following primitive land plants in order of their successive sequence: Zosterophyllophytina, Lycophytina, Rhyniophytina.
Rhyniophytina -> Zosterophyllophytina -> Lycophytina
The Paleozoic spore plants included
1) . Scale trees
2) . Horsetails
3) . Ferns
Ferns reproduce by spreading
spores.
Megaphylls originated when Rhyniophyte V-branching developed
umbrella-like webbing.
Sporangia are the
spore sacs.
In ferns, where are the spore sacs located?
At the leaf margins
“Naked seed” plants are called
gymnosperms.
Describe the earliest seed plants.
Seed ferns. They had leaves like ferns but seeds, not spores.
Ferns are linked to seed plants through
seed ferns.
The seeds of seed ferns are located at
the leaf mid-veins.
Mesozoic seed plants include
seed ferns, cycads, Ginkgo, and conifers.
“Protected seed” plants are called
angiosperms.
Animals without backbones date from the
Cambrian explosion
When did the Cambrian explosion occur?
570-530 Ma ago.
Summarize the phylogenetic tree
Protists and sponges -> Lower invertebrates (jelly fish, flatworms) => Path divides -> 1). Insects 2). Humans
Describe protists
Unicellular eukaryotes
What are protozoans?
Non-photosynthetic protists
In the phylogenetic tree, sponges are termed
porifera.
In sponges, spicules serve to provide
shape.
In the phylogenetic tree, all animals belong to the class
metazoa.
In the phylogenetic tree, all animals except sponges are termed
eumetazoa.
How many cells layers are in the tissues of coelenterates?
Two (ectoderm, endoderm).
Coelenterates include
corals, jellyfish.
How many cell layers are in the tissues and organs of Bilateria?
Three
Bilateria include
flatworms, arthropods, vertebrates, brachiopods, echinoderms, mollusks.
What are the earliest bilaterians?
Flatworms
latyhelmenthes are the
flatworms.
The primary characteristic of acoelomates is
a body composed of slid tissue (no coelom).
A coelom is
the main body cavity between the body wall and the digestive tract.
Eumetazoans that lack coeloms are called
Acoelomates
The term brachiopod means
“arm-foot” (for anchoring)
A pedicle is a
fleshy “arm-foot”.
A lophophore is a
leaf rake-shaped feeding apparatus.
Bryozoans are
fan-shaped colonies of tiny animals with lophophores for feeding,
The term pelecypod means
“axe-foot” (clams)
Molluscs include which 3 groups?
1) . Pelecypods
2) . Gastropods
3) . Cephalopods
The term gastropod means
“stomach-foot” (snails)
The term cephalopod means
“head-foot” (squids).
Which group has a septum?
Cephalopod
Relations among the many kinds of metazoans include:
1) . rRNA Tree of Life
2) . Embryos, larvae
3) . Adult tissues, form
Name two species of lower invertebrates
Jellyfish, flatworms
Platyhelmenthes are commonly known as
flatworms.
Why do coeloms matter?
Coelomates can burrow = improved feeding.
Name a modern Annelid
1). Earth worm
List 2 characteristics of Annelids
1) . Segmented body
2) . No legs
List 2 characteristics of Arthropods
1) . Segmented body
2) . Legs
What do Arthropods have that Annelids do not have?
Legs
The term arthropod means
“jointed-foot”
What are the index fossils for the Paleozoic era?
Trilobites
Compound eyes are a characteristic of all
Arthropods.
The left branch of the phylogenetic tree includes all
Protostome coelomates
The term protostome means
“first-mouth”.
Define the term “blastopore”
Opening in hollow ball of cells formed early in embryonic development.
Protostomes are
animals in which the blastopore becomes the mouth
List several protostomes
flatworms, brachiopods, annelids, arthropods.
The right branch of the phylogenetic tree includes all
deuterostome coelomates.
The term “deuterostome” means
“second mouth”.
The blastopore in protostomes becomes the
mouth.
The blastopore in deuterostomes becomes the
anus.
Name several deuterostomes
echinoderms, chordates.
The term “echinoderms” means
“spiny-skinned”.
List two characteristics of echinoderms
1) . 5-point radial symmetry
2) . Tube feet
List several echinoderms
sea-stars, sea urchins, sand dollars.
A crinoid is a
sea-lilly
Chordates are deuterostome animals possessing which 3 things?
1) . Gill slits
2) . Notochord
3) . Dorsal nerve chord
What is a notochord?
A lengthwise flexible rod, provides support in vertebrate embryos.
Homologous organs, structures, and biochemistry are those which
have same or similar function, same evolutionary derivation.
List an example of a homologous trait
Bird vs. bat wing (same evolutionary derivation)
Analogous organs, structures, and biochemistry are those which
have same or similar function, but a different evolutionary derivation.
List an example of an analogous trait
Bird wing vs. insect wing (e.g. butterfly wing, which has veins)
List the sequence of vertebrate evolution
Fish -> amphibians -> reptiles -> birds and mammals
List an ectothermic group of animals
fish
Amphibians are considered to be semi-terrestrial because
they rely on water for reproduction.
Like fish, amphibians are
ectotherms.
An amniote egg is a
yolk-bearing hard-shelled egg of reptiles and birds.
Describe reptiles
terrestrial, amniote tetrapods, majority are ectotherms
Name several reptiles
Lizards, snakes, turtles, crocodiles, dinosaurs.
Describe the evolution of birds
Dinosaurs -> Archaeopteryx (feathers = modified reptilian scales) -> Modern birds (fused fingers, teeth lost, short tail)
The earliest fossil bird is the
Archaeopteryx
List the reptilian features of the Archaeopteryx
toothed beak, wing claw, long tail with many vertebrae
List the avian character of the Archaeopteryx
airfoil wing with contour feathers.
List the characteristics of mammals
Terrestrial, aquatic, and flying endotherms; milk; hair (modified scales)
When did mammals arise?
Early in the Mesozoic
Name the meteor which wiped out forests 65 Ma
Yucatan meteorite
When did placental mammals come about?
65 Ma
The Cenozoic is the age of
mammals.
