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MODULE 4 WEEK 7 – Evolution and Diversity
Diversity of Animals
I. Features of the Animal Kingdom
●Sperm form is diverse and includes cells with
INTRODUCTION
flagella or amoeboid cells to facilitate motility
ASEXUAL REPRODUCTION
● All animals are:
- eukaryotic, multicellular organisms Asexual reproduction is:
- heterotrophic: ingesting living or dead
● present in those without backbones, some fish,
organic matter
amphibians, and reptiles
● absent in birds and mammals
● Most animals:
- are motile
- reproduce sexually: offspring pass through a ⮚ most common forms: budding and fragmentation
series of developmental stages that ⮚ found in invertebrates and rare vertebrates:
establish a determined body plan parthenogenesis
BODY PLAN CLASSIFICATION FEATURES OF ANIMALS
- refers to the shape of an animal Animals are classified according to morphological and
- symmetrical (except for sponges) developmental characteristics, such as a body plan.
COMPLEX TISSUE STRUCTURE Other characteristics that contribute are:
- no. of tissue layers formed during
There are four main types of animal tissues: development
- presence/absence of internal body cavity
1. NERVOUS TISSUE - features of embryological development
- contains neurons, or nerve cells, which
transmit nerve impulses BODY SYMMETRY
2. MUSCLE TISSUE Animals may be:
- contracts to cause all types of body
movement from locomotion of the organism 1. ASSYMETRICAL
to movements within the body itself - no pattern or symmetry
- Example: sponge
3. CONNECTIVE TISSUE
- provide many functions, including transport 2. RADIAL SYMMETRY
and structural support - multiple planes of symmetry all cross at an
- comprised of cells separated by extracellular axis through the center of the organism
material made of organic and inorganic - Example: sea anemone
materials
- Example: blood & bone 3. BILATERAL SYMMETRY
- there is only one plane of symmetry that
4. EPITHELIAL TISSUE creates two mirror-image sides
- covers the internal and external surfaces of - Head and tail = anterior vs posterior
organs inside the animal body and the - Back and underside = dorsal versus ventral
external surface of the body
LAYERS OF TISSUES
ANIMAL REPRODUCTION AND DEVELOPMENT GERM LAYER
Most animals have diploid body (somatic) cells and a - layering of early tissues during embryonic
small number of haploid reproductive (gamete) cells development
(meiosis) - will give rise to future body tissues and
organs
SEXUAL REPRODUCTION AND EMBRYONIC
DEVELOPMENT II. Sponges and Cnidarians
III. Flatworms, Nematodes, and Arthropods
During sexual reproduction: IV. Mollusks and Annelids
● male and female gametes of a species combine
in a process called fertilization (produce
zygote)
MODULE 4 WEEK 7 – Evolution and Diversity
Diversity of Animals
I. Features of the Animal Kingdom
●Sperm form is diverse and includes cells with
INTRODUCTION
flagella or amoeboid cells to facilitate motility
ASEXUAL REPRODUCTION
● All animals are:
- eukaryotic, multicellular organisms Asexual reproduction is:
- heterotrophic: ingesting living or dead
● present in those without backbones, some fish,
organic matter
amphibians, and reptiles
● absent in birds and mammals
● Most animals:
- are motile
- reproduce sexually: offspring pass through a ⮚ most common forms: budding and fragmentation
series of developmental stages that ⮚ found in invertebrates and rare vertebrates:
establish a determined body plan parthenogenesis
BODY PLAN CLASSIFICATION FEATURES OF ANIMALS
- refers to the shape of an animal Animals are classified according to morphological and
- symmetrical (except for sponges) developmental characteristics, such as a body plan.
COMPLEX TISSUE STRUCTURE Other characteristics that contribute are:
- no. of tissue layers formed during
There are four main types of animal tissues: development
- presence/absence of internal body cavity
1. NERVOUS TISSUE - features of embryological development
- contains neurons, or nerve cells, which
transmit nerve impulses BODY SYMMETRY
2. MUSCLE TISSUE Animals may be:
- contracts to cause all types of body
movement from locomotion of the organism 1. ASSYMETRICAL
to movements within the body itself - no pattern or symmetry
- Example: sponge
3. CONNECTIVE TISSUE
- provide many functions, including transport 2. RADIAL SYMMETRY
and structural support - multiple planes of symmetry all cross at an
- comprised of cells separated by extracellular axis through the center of the organism
material made of organic and inorganic - Example: sea anemone
materials
- Example: blood & bone 3. BILATERAL SYMMETRY
- there is only one plane of symmetry that
4. EPITHELIAL TISSUE creates two mirror-image sides
- covers the internal and external surfaces of - Head and tail = anterior vs posterior
organs inside the animal body and the - Back and underside = dorsal versus ventral
external surface of the body
LAYERS OF TISSUES
ANIMAL REPRODUCTION AND DEVELOPMENT GERM LAYER
Most animals have diploid body (somatic) cells and a - layering of early tissues during embryonic
small number of haploid reproductive (gamete) cells development
(meiosis) - will give rise to future body tissues and
organs
SEXUAL REPRODUCTION AND EMBRYONIC
DEVELOPMENT II. Sponges and Cnidarians
III. Flatworms, Nematodes, and Arthropods
During sexual reproduction: IV. Mollusks and Annelids
● male and female gametes of a species combine
in a process called fertilization (produce
zygote)
