Unit 1 Zoology Flashcards
How many phyla were present at the end of the Cambrian Explosion?
100+
How many major phyla of living multicellular animals exist today?
32
What brought about the major body plans?
Extensive selection
Protozoan
Single cell organism, member of Protista
Metazoan
Multicellular, animals.
Protoplasmic
Single cell creature that can perform all the same functions of a more complex animal.
Example of protoplasmic
Paramecium
Cellular
Cells become specialized to work as a whole organism. These cells are incapable of living alone and show division of labor.
Tissue
Cells work closely together as a unit to perform a common function.
Example of tissue
Heart tissue, a jellyfish.
Organ
Many tissues work together in one organ. Usually one type of tissue carries the burden of the organs chief functions while the other tissues perform supportive roles.
Examples of organs
Heart, lung, liver
What level do most metazoans operate on?
Organs
System/organ system
More than one organ works together to achieve a goal or set of goals. Usually operates basic bodily functions.
Example of system/organ system
Human, fish, reproductive system
What level do most animals work on?
System/organ system
How many organ systems can metazoans exhibit?
11
Integumentary
Covers and protects the body from external pathogens
Components of integumentary system
Skin, hair, fur, feathers, exoskeleton, horns, nails, claws, talons.
Skeletal
Support, movement, makes red blood cells, protection
Components of skeletal system
Bones, cartilage, ligaments
Muscular
Movement of skeleton, movement of internal organs, movement of blood
Components of muscular system
Smooth, skeletal, and cardiac muscle
Digestive
Breaks down and absorbs food
Digestive components
Mouth, esophagus, stomach, intestines, liver, pancreas
Respiratory
Exchange oxygen for carbon dioxide.
Respiratory component
Lungs, trachea
Circulatory
Transports oxygen, nutrients, CO2, nitrogen, hormones, minerals, waste, etc.
Circulatory components
Heart, blood vessels, red blood cells, platelets, plasma, lymph
Urinary
Filters out waste, collects waste in bladder
Components of urinary
Kidney, urinary bladder, associates ducts (ureter, urethra, etc)
Nervous
Receives and interprets stimuli, conducts liquid impulses throughout the body
Nervous components
Brain, nerves, neurons, spinal chord
Endocrine
Regular bodily functions, blood chemistry, chemical communications
Endocrine components
Pituitary, adrenal, thyroid
Reproductive
Continuation of the species, makes babies.
Reproductive components
Testes, ovaries, associates structures
Immune
Defend the body against internal pathogens
Immune components
Lymph nodes, lymphatic vessels
What is the advantage of more complex grades of Metazoan organization?
They get bigger.
What are the four benefits larger organism have?
1) less energy spent per gram of mass used
2) easier to maintain body temperature
3) less energy needed to maintain homeostasis
4) protection
What are the flaws of larger organisms?
1) a large animal has less surface area compared to its volume than a smaller animal
What are two solutions to being a larger organism that needs gas exchange?
Folding/flattening of organism, circulatory + respiratory system
Copes Law of Phyletic Increase
Lineages began with small individuals and eventually evolved into larger forms.
Intercellular
Inside the cell
Extracellular
Outside the cell
Interstitial fluid
Tissue fluid surrounding the cells.
Architectural Extracellular structural elements function
Provide structure
What are examples of architectural Extracellular structural elements?
Collagen fibers and calcium matrix
Histology
Study of tissues
What are the three germ layers?
Ectoderm, endoderm, mesoderm
Ectoderm
Becomes skin, hair, brain, nerves, spinal chord, exoskeleton, horn, nail, (integumentary and nervous system)
Endoderm
Becomes the tube (gastrointestinal)
Mesoderm
Becomes lung, heart, everything in middle EXCEPT tube
Epithelial tissue location
It lines everything.
How does one identify epithelial tissue?
Look for space
What does epithelial tissue do?
It provides protection and internal lining, often modified into glands.
All have an underlying basement membrane (condensation of the ground substance of connective tissue)
What is the significance of the basement membrane?
This is where the epithelial divides/is born.
How does epithelial tissue receive O2 and nutrients and why?
It receives it through diffusion, because blood vessels do not penetrate it.
Simple epithelial
Single layered, found in all Metazoa
Stratified epithelial
Multi layered, restricted to vertebrates
Epithelial tissue
A thin sheet of cells.
Connective tissue
Serves in binding and supportive functions
Where is connective tissue located?
Everywhere in the body.
What is connective tissue made up of?
Few cells, many Extracellular fibers, ground substance of matrix that the fibers are embedded in.
Loose connective tissue
Has fibers and both fixed and wandering cells in a syrupy matrix. Few nuclei.
Examples of loose connective tissue.
Mesentary, adipose
Dense connective tissue
Characterized by densely packed fibers. Several nuclei.
Examples of sense connective tissue
Ligaments, tendons.
What protein is connective tissue made of?
Collagen
What is the most abundant tissue in the animal kingdom?
Collagen
What are three of the connective tissue/vascular tissue?
Blood, lymph, and tissue fluid.
What kind of tissue is cartilage?
Connective tissue.
What kind of tissue is bone?
Calcified connective tissue
Muscular tissue
Most abundant tissue in most animals.
What germ layer does muscular tissue originate from?
Mesoderm
What is the muscle fiber cell specialized for?
Movement.
Skeletal muscle
Voluntary, striated, fibers are really long, more than one nuclei per cell that are pushed to the side.
Smooth muscle
Involuntary, NOT striated, single nuclei in the middle of the cell.
Cardiac muscle
Involuntary, striated, separated by intercalary disks, single nucleus per cell.
Where is cardiac muscle found?
Only in the heart.
Myofibrils
Contractile elements
Sarcoplasm
Unspecialized cytoplasm of muscles.
Nervous tissue
Receives, conducts, and interprets stimuli
Neuron
Basic functional unit, conducts impulses
Neuroglia
Non nervous cells that insulate neuron membranes and serve various supportive functions that support the neurons.
Spherical symmetry
Any plane that passes through the central point divides the body into mirrored halves.
Radial symmetry
Any plane passing through the longitudinal axis divides the body into mirrored halves.
What two body types usually appear in sessile animals?
Radial and spherical.
What is an advantage of radial symmetry for sessile organisms?
They can attack from all sides.
Biradial symmetry
When an animal is radial except for some paired feature that allows only two mirrored halves.
Animals with radial symmetry
Sea stars, sea urchins
Animals with biradial symmetry
Sea walnuts
Bilateral symmetry
When an organism can be cut down the sagittal plane into two mirrored halves.
Which body symmetry usually allows for cephalization?
Bilateral symmetry
What is cephalization?
An animal has all its sensory organs in one central area, and had a head.
Animal with bilateral symmetry
Humans, most four legged animals.
What is the advantage of cephalization?
Since all the organs are gathered in one area, usually moving in front of the body, an animal can sense what’s coming before its body gets there.
What is advantage of being bilateral?
Speedy movement
Asymmetry
No symmetry.
Example of asymmetry
Sponges
Anterior
Head end
Posterior
Opposite, tail end
Dorsal
Back side
Ventral
Front or belly side
Medial
Midline of the body
Lateral
To the side
Distal
Part that’s far from the body
Proximal
Parts near to the body
Frontal plane
Divides the body into dorsal and ventral halves
Transverse plane
Separates anterior and posterior
Pectoral
Chest region or area supported by forelegs
Pelvic
Hip region, supported by forelegs.
Coelom
Tube within a tube
What is the major evolutionary innovation of bilateria?
Coelom
What is the coelom?
Fluid filled space around the tube.
What are the three ways a coelom helps an organism?
1) increased flexibility
2) protects organs and gives them space
3) allows for transportation of molecules and increased surface area by making places to observe
Hydrostatic skeleton
The movement of worms that aid in burrowing and movement
Acoelomate bilateria
No body cavity, like flatworms.
What do acoelomate creatures have instead?
They have a mass of spongey parenchyma cells.
Pseudocoelomate bilateria
Fake coelom
What is pseudocoelomate bilateria missing?
An interior lining of mesoderm.
What is an example of a pseudocoelomate animal?
Nematode
Eucoelomate bilateria
True coelem
What does a eucoelomate have that makes it that?
A layer of mesoderm.
Schizoceolus
Formation involves splitting of mesoderm bands that originate from cells in the blastophore region.
What is another word for schizoceolus?
Protosomes
Enterocoelus
Formation comes from pouches of the archenteron or primitive gut.
What is another word for Enterocoelus?
Deuterosomes
Metamerism
Segmentation of a body.
What is each segment called?
Somites or metameres.
What are the three goals of taxonomy set forth by systematic zoologist?
1) discover all animals
2) discover all past animals and figure out evolution
3) classify animals according to evolutionary relationships.
Taxonomy
Formal system for naming and classifying species.
Systematics
Broader science of classifying organisms based on similarity, biogeography, etc.
Character
Any feature a taxonomists uses to study variation within and among species.
Homology
Similar characteristics that suggest common ancestry.
No homologous or homoplasy
Characters that are similar but not related.
Phylogeny
Based on the study of characters among various species. Relate all living and extinct species.
Adaptive zone
Created by George Gaylord Simpson. A branch in a family tree represents a distinct adaptive zone, or a distinct way of life. Cause animals from the same area to evolve differently.
Cladistics
A series of species that share derived characteristics from a clade.
Cladogram
Nested hierarchy of clades.
Synapomorphy
Derived characters shared by members of a clade.
Derived character states
Characters that arose later, not in the ancestral form.
Outgroup
Shows if a character occurred both within and outside a common ancestor.
What animal works on the protoplasmic level?
Paramecium
What animal works on the cellular level?
Sponge
What animal works on the tissue level?
Jellyfish
What animal works on the organ level?
Planarian
What animal works on the system level?
Humans
What is the advantage of more complex grades of Metazoan organization?
They get bigger.
