zoology intro

Protozoans

unicellular eukaryotes that act like animals

Amoeba, Paramecium

Give 2 protozoans

Amoeba

moves using pseudopodia (false feet)

Paramecium

Uses cilia for movement, has oral groove for feeding

please Porifera

come Cnidarians

play Platyhelminthes

now Nematodes

all annelids

my mollusks

eager echinoderm

children chordates

Major animal groups

Porifera

(sponges)

no tissue or organs, filter feeders

Cnidarians

sea jellies, anemones, corals, hydra

radial symmetry

cnidocytes (stinging cells)

Platyhelminthes

Flatworms, planaria, flukes, tapeworms

First to show bilateral symmetry and simple organs

Nematodes

(roundworms)

Ascaris, schistosoma
Tube-like digestive tract, pseudocoelom

Annelids

Segmented worms, eartworms, leeches

True segmentation (metamerism), coelomates

Mollusks

Snails slugs chitons cephalopod (octopus)

Soft-bodies, often with shells; cephalopods = smart

Echinoderms

Starfish, sea cucumbers, sea urchins

radial as adults, water vascular system, endoskeleton

Chordates

fish amphibians reptiles birds mammals

all have notochord at some point in life

C Ctenophores
U
N Nemerteans

T Tardigrades

Minor groups

Ctenophore

Similar to cnidarians but with 8 rows of cilia

Nemerteans

ribbon worms, long and flat

Tardigrades

Tiny “water bearers,” extremely resilient

Spherical

type of symmetry that has infinite mirrored planes

(mostly unicellular)

ex. ball

Anatomy

the study of the biological form of an organism

Physiology

the study of the biological functions an organism performs

Symmetry

refers to balanced proportions

Symmetry

correspondence in size and shape of parts on opposite sides of a median plane

Spherical Symmetry

any plane passing through the center divides a body into equivalent or mirrored halves

Spherical Symmetry

Found mainly on unicellular forms

Spherical Symmetry

best suited for floating and rolling

Radial symmetry

Body can be divided into similar halves by more than two planes passing through the longitudinal axis

Radial symmetry

Usually sessile, free floating or weakly swimming

sea anemone, Hydra sp., sea star, sea urchin

Examples of species with radial symmetry

Biradial symmetry

only two planes passing through the longitudinal produce axis mirrored halves because of some part that is single or paired

Comb jelly

example of biradial symmetry

Bilateral symmetry

body can be divided along a sagittal plane into mirrored portions – right and left halves

Bilateral Symmetry

better suited for directional (forward movement)

Arthropods, vertebrates

Examples of bilateral symmetry

Fiddler crabs, flounder, snails, sponges

Example of no or loss of symmetry

Segmentation/ Matamerism

serial repetition of similar body segments along the longitudinal axis of the body

metamere/ somite

Other term for segment

True segmentation

segments consist of parts from multiple organ system

False segmentation

nimal’s body looks like it’s divided into segments, but those segments are not true or functional segments.

Tapeworm

example of false segmentation

Segments

units of reproductive system

Regionalization

It’s the division of an animal’s body into specialized regions, each with different functions or structures.

1. head

2. Thorax

3. Abdomen

4. Tail

common body regions

Cephalothorax

Head + thorax

Trunk

Thorax + abdomen

Appendages

body parts that stick out (or extend) from the main body.

Antenna

Sensory appendage of a grasshopper

Legs + wings

Locomotory appendage for grasshoppers

mouthparts

Feeding appendage of the grasshopper

tentacles

Common appendage of cnidarians, mollusks, ctenophore, and some worms

3 pairs ( 6 legs )

How many legs, locomotory appendage of insects

1. Protoplasmic grade of organization

2. Cellular grade

3. Cell-tissue grade

4. Tissue-organ grade

5. organ-system grade

Levels of Organization in Organismal Complexity

Protoplasmic grade of organization

• unicellular orgs (ex. paramecium)

• All life function are combined within the boundaries of a single cell

protoplasmic grade

• Protoplasm is differentiated into organelles

Cellular grade

• aggregation of cells that are functionally differentiated

cellular grade

a division of labor is evident

cell-tissue grade

aggregation of similar cells into definite patterns of layers, thus becoming a tissue

tissue-organ grade

an aggregation of tissues into organs

Organ-system grade of organization

organs work together to perform some function

Organ-system grade of organization

systems are associated with basic functions

Somatic ( epithelial, connective, muscular, nervous) and Reproductive ( sperm and egg)

2 types of cells

same as cells

2 types of tissues

cystology/ cell biology

cell field of study

Histology

Tissue field of study

anatomy

field of study for organs and organ system