Transcript 6 Kingdoms of Life Part 2: Plants and Animals

6 Kingdoms of Life Part 2:
Plants and Animals
Asexual vs. Sexual
• Recall that all organisms reproduce either sexually or
asexually
– Sexual- there is a combining of
genes from 2 parents but NOT
always with egg and sperm
(meiosis followed by fertilization)
– Asexual- the offspring are
reproduced by copying the DNA
of one parent (binary fission or budding)
Plant Kingdom
• All plants are multicellular
• Their cells have a cell wall-cellulose
• Autotrophs-make own
carbs for energy through
photosynthesis
• Can reproduce sexually,
asexually, or both
What Plants Need to Survive…
•
•
•
•
Sunlight
Water
Vitamins/Minerals
Gas Exchange
(O2 and CO2)
• A method of transport
to move water and other materials
to all parts of plant.
What Plants Need to Survive…
• Phototropism- a method of homeostasis and response
to a light stimulus in which the direction of growth is
determined by the direction of the light source.
• Can plants move?
General Life Cycle Plants
• Two alternating phases:
1) Diploid Phase—2 copies of all genes (Sporophyte)
-Sporophyte makes spores by meiosis.
-Spores develop into gametophyte form of plant.
2) Haploid Phase– 1 copy of all genes (Gametophyte)
-Gametophyte produces male and female gametes
by mitosis—makes more haploid cells.
-Gametes eventually join to form sporophyte.
Alternating Phases: Plant Life Cycle
Example of a Plant Life Cycle
Evolutionary Trends and Plants…
• Ancestors of 1st plants were multicellular green
algae.
• Plants have evolved specific adaptations to help
them survive in a variety of different climates.
• There are four major groups of plants which are
separated by three distinct features:
1. Water conducting tissue (vascular).
2. Seeds
3. Flowers
Green Algae Ancestor
ANGIOSPERMS
GYMNOSPERMS
PTERIDOPHYTES
BRYOPHYTES
4 Major Groups of Plants
1. Plant groups by vascular tissue
NO
VASCULAR
TISSUE
VASCULAR
TISSUE
1. Bryophytes (Moss)
2. Pteridophytes (Ferns)
3. Gymnosperms (Cone bearing plants)
4. Angiosperms (Flowering plants)
Vascular Plants
•Vascular- internal transportation system
• Xylem – water carrying tubes
• Phloem – sugar carrying tissues
• Enabled plants to evolve into larger specimens.
• Pteridophytes (Ferns), angiosperms and gymnosperms
are all vascular
Nonvascular Plants
• Simplest of all land dwelling
plants
•Bryophytes
•Nonvascular (no “veins”)-lack an
internal means for water
transportation
•Obtain/transfer water by osmosis
•Grow moist, shaded areas
•No true roots, leaves, stems
•Rhizoids anchor plant to ground
2. Plants Groups by Seeding
NO
SEEDS
SEED
PLANTS
1. Bryophytes (Moss)
2. Pteridophytes (Ferns)
3. Gymnosperms (Cone bearing plants)
•
Form seeds in “cones.”
4. Angiosperms (Flowering plants)
•
Form seeds inside of “flowers.”
Seed Plants
• Seed plants do not require water for reproduction like
mosses so can live in most environments
• Seed plants produce “pollen” which is the male gamete
and ovaries (ovules) which are female
• Pollen is extremely small and light and is easily carried
by wind or small animals
Seeds
• Plant gametes: Egg and sperm (pollen) of plant join
together to form seed
• Seeds are embryos of seed plants encased in a
protective coating and surrounded by a food supply.
Bryophytes
• Do not produce seeds, but have egg
and sperm only which must meet to
form a new bryophyte.
•Require water for fertilization to
transport gametes
Pteridophytes (Ferns)
• No seeds—have egg and sperm
join and produce spores
• Contain vascular tissue
• 1st true land plants
• Gymnosperms
– Means “naked seed”
– Oldest vascular, seedproducing plants
Gymnosperms
• Seeds are exposed
• Most common are “conifers”
(spruce, firs, pines, etc.).
• Most have needles instead of
leaves.
• Most conifers are “evergreens”
meaning they keep their
needles (leaves) year round.
• Angiosperms
- Means “enclosed seed”
– Flowering
– Most common of all land
plants
3. Plant groups by flowers
NO
FLOWERS
FLOWERS
1. Bryophytes (Moss)
2. Pteridophytes (Ferns)
3. Gymnosperms (Cone bearing plants)
•
Form seeds in “cones.”
4. Angiosperms (Flowering plants)
•
Form seeds inside of “flowers.”
Flowers
• Angiosperms are the only flowering plants
• Flowers attract animals to support pollination
(very efficient)
• Seeds develop inside ovary within a “flower”
• After “fertilization” seed within flower develops
into “fruit”
• Angiosperms are typically
classified in two groups:
1. Monocots
2. Dicots
Life Spans of Angiosperms
• Annuals- survive one season
• Biennials- take 2 years to
complete life cycle
• Perennials- live many years
•All animals are:
Animalia Kingdom
—Multicellular: cells lacking a cell wall
—Heterotrophs
—Capable of movement at some point
in their lives.
—95% of all animals are invertebrates
Criteria for Animal Classification
• Skeletal Characteristics
– Invertebrates -have a hard external skeleton made of chitin
known as an exoskeleton
– Vertebrates have a hard internal skeleton made of bone or
cartilage
• Kingdom
Phylum
Class
Order
Family
Genus
Species
Major phylums of animals
are…
• Nine major phyla of animals:
M
1. Poriferans (sponges)
o
2. Cnidarians (jellyfish)
r
3. Flatworms (tapeworm)
e
4. Roundworms (heartworm)
c
5. Annelids (earthworm)
o
6. Mollusks (clam)
m
p
7. Arthropod (grasshopper)
l
8. Echinoderm (starfish)
e
x
9. Chordate (human)
Invertebrates
• Porifera
– Sponges
– Invertebrates
– Sponges are filter feeders and depend
on the movement of water to obtain
nutrients/oxygen
– Digestion is intracellular –no stomach
– Reproduce asexually by budding or
sexually through egg and sperm
• Cnidarians
– Jellyfish, corals, and other stingers. . . Their stinger is called a
nematocyst
– Invertebrates
– Belizes coral reef
• Mollusks
– Octopi, squid, clams, oysters, snails, slugs
– Invertebrates
– Reproduce sexually
– Cool Octopus video
• Platyhelminthes (flat worms)
– Tapeworms & Liver Fluke & Planaria
– Hermaphrodites-fertilize their own sex cells internally then
zygotes are released into water to hatch
– Invertebrates
– Sexual or asexual reproduction
Human liver fluke
• Nematodes (roundworms)
– Heartworms, hookworm, pinworms
– One of the most diverse animal phyla
– Many are parasites
– Sexual reproduction
• Annelids (segmented worms)
– Worms & leeches
– Invertebrates
– Worms mating
• Echinoderms
– Starfish, sea urchins, sea cucumbers
– They have a hard exoskeleton under their skin
– Invertebrates
• Arthropods
– Shell fish, arachnids & BUGS!
– Invertebrates—have exoskeleton
– Reproduce sexually
• Chordates
– All other animals that have a backbone of some form
– Vertebrates
Trends in Animal Evolution
• Complex animals tend to have…
1. Specialized cells and organs
2. Bilateral body symmetry
3. A definite head with sensory organs
(cephalization)
4. A body cavity
5. Complex embryonic development
Trend #1: Specialized Cells and Organs
• The more complex the animal, the more
“specialized” its cells become.
• Cells  Tissues  Organs  Organ system.
• Some animals have no organs!
Trend #2: Body Symmetry
• With the exception to sponges, every animal
exhibits one of two types of body symmetry:
1. Radial symmetry
2. Bilateral symmetry
Radial Symmetry
• Imaginary plane can pass through a central axis
in any direction
Bilateral Symmetry
• Single plane can divide the body into two equal
halves
• Animals with bilateral symmetry have a right
and left side and usually have segmented bodies
Trend #3: Cephalization
• Animals with bilateral symmetry have a definite head
• Cephalization is the concentration of sense organs and
nerve cells in the anterior end (front end) of the body
• Animals with this trait tend to respond in more complex
ways to their environment
Trend #4: Body Cavity Formation
• Most animals have a body
cavity in which all major
organs are attached. This
area is called a coelom
• Provides room for organs
to grow and expand
• Less complex animals do
not have this area. They
are called acoelomates
Trend #5 Embryo Development
During gastrulation, cells
begin to differentiate
(specialize).
Worms, mollusks, arthropods, etc. 
Chordates and Echinoderms 
Protostomes vs. Deuterostomes
• In protostomes (worms, mollusks, and
arthropods), blastopore develops into mouth.
• In deuterostomes (echinoderms and chordates),
blastopore develops into anus.
• Three layers of embryonic cells (germ layers):
1. Endoderm – Develops into digestive and respiratory tracts.
2. Mesoderm – Develops into muscles, heart, sex organs, and
kidneys.
3. Ectoderm – Develops into brain, sense organs, and skin.