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organisms with one tinsel flagellum, and one whiplash flagellum; includes oomycetes, chrysophytes, diatoms, brown algae, and certain other groups


comprised of yellow-green algae, golden-brown algae, and diatoms

golden algae

A biflagellated, photosynthetic protist named for its color, which results from its yellow and brown carotenoids.

yellow-green algae

A rare chromist that derives its color from a yellow pigment that masks chlorophyll and is found mostly in freshwater


A unicellular photosynthetic alga with a unique, glassy cell wall containing silica.


chemical compound that is an oxide of silicon with the chemical formula SiO2. found in the cell walls of diatoms

brown algae

One of a group of marine, multicellular, autotrophic protists, the most common type of seaweed. Brown algae include the kelps.


water molds, mildews: lack chloroplasts, decomposers

water mold

funguslike protist composed of branching filaments of cells


green algae; live in fresh water, although many are marine, have complex life cycles


Type of living green algae that on the basis of nucleotide sequencing and cellular features is most closely related to land plants.

red algae

most of the world's seaweeds. contain chlorophyll and red pigment. live in tropical waters. multicellular. grow less than 1 meter in length. can grow 260 m below the surface.

downy mildew

major plant pathogens that include the species responsoblf fo rthe mid 1800s Irish potato famine


polysaccharide consisting of glucose monomers that reinforces plant-cell walls


Type of tissue that transports food and water


A temporary, foot-like extension of a cell, used for locomotion or engulfing food


mutualistic arrangements between fungi and photosynthetic organisms


A richly diverse group of heterotrophs that may be either saprobes or parasites


organism that obtains food from decaying organic matter


the filaments in mycelium. Each consists of cells of interconnecting cytoplasm and chitin-reinforced walls


complex carbohydrate that makes up the cell walls of fungi; also found in the external skeletons of arthropods


the vegetative part of a fungus consisting of a mass of branching threadlike hyphae

extracellular digestion and absorption

the process in which fungal cells take in nutrients

Seedless Vascular

contain vascular tissue, produce lignin, have true: roots, stems, and leaves


A flowering plant, which forms seeds inside a protective chamber called an ovary.


a woody, vascular seed plant whose seeds are not enclosed by an ovary or fruit


A mutualistic association between plant roots and fungi.


Asymmetrical animals in which a sheet of flattened, nonflagellated cells is attached to the sharp spikes of a single cell's extracellular matrix. The extracellular matrix is made up of a single cells secretions


group of plants that have specialized reproductive organs but lack vascular tissue; includes mosses and their relatives


Free living, sexually immature stage in the development of many kinds of animals, one that precedes the adult form


one of the simplest animals known, asymmetrical, lacks true tissue, has only 4 different types of cells, and is the closest animal relative of choanoflagellates


first appeared around 600 million years ago and flourished until the cusp of the Cambrian 542 million years ago. Are believed to be animals, but some say they are not. Resemble discs, tubes, mud-filled bags or quilted mattresses. Some paleontologists have suggested that these represent completely extinct lineages that do not resemble any living organism.

Cambrian Period

from 544 million to about 500 million years ago. when the extreme diversification of life forms occured. Changes in land mass, sea level, and climate change.


Bilateral, soft-bodied animals with a reduced coelom.


Skirtlike extension of the body mass that drapes back upon itself


In gastropods, a developmental process in which the visceral mass rotates up to 180°, causing the animal's anus and mantle cavity to be positioned above its head.


a soft-bellied ocean dwelling mollusk whose foot is adapted to form tentacles around its mouth. Supreme predators of the sea during the Cambrian period. All but one do not have a shell. Move by jet propulsion


a tube running from the inside of an animal to the outside so that atmospheric pressure forces the liquid through the tube. Used by cephalopods to move.


invertebrate having jointed limbs and a segmented body with an exoskeleton made of chitin. Have a complete gut, a greatly reduced coelom, an open circulatory system, and are bilateral animals.


the exterior protective or supporting structure or shell of many animals (especially invertebrates) including bony or horny parts such as nails or scales or hoofs. Restricts water loss and helps support the weight of a body removed from the buoyancy of water


periodic shedding of a too-small body covering in arthropods.under normal hormonal control


a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's form or structure through cell growth and differentiation.


a class of small arthropod animals that has three separate sections to their bodies: head, thorax, abdomen.


insects, Compact cluster of spore-bearing structures found in seedless vascular plants

Malphigian Tubules

excretory system for insects, allows wastes to be excreted and H₂0 to be reabsorbed


Single-celled, but have a nucleus. Most have mitochondria, golgi bodies, and endoplasmic reticulum. Have more than one chromosome. Many have chloroplasts. Divide by way of mitosis, meiosis, or both.


Seven, a horizontal, underground stem that produces new leaves, shoots, and roots


Pertaining to a taxon derived from a single ancestral species that gave rise to no species in any other taxa.


pertaining to a group of taxa derived from two or more different ancestors


Multicelled heterotrophs that ingest other organisms or some portion of them


The sibling taxon of animals and fungi. Is a model for the origin of animals

What type of tissue do all types of animals contain?



Start of the outer part of epidermis and the nervous system. In the embryo.


Start of the gut's inner lining and the organs derived from it. In the embryo


Gives rise to many internal organs. In the embryo. It played a big role in the evolution of large, internally complex animals


Filament-like absorptive structures that increase the surface area of cells


The body has a front to back axis, with an anchor/ leading end and a posterior/ trailing end.


Concentration of sensory receptors at the anterior end of an animal. Evolved into a distinct head and a brain.

Radial Symmetry

Body parts are organized around the main axis. Found mostly in water animals


Organisms in which the mouth develops before the anus. Examples: Arthropods, Mollusks


Undergoes radial cleavage and the anus forms before the mouth.


a body cavity completely lined with mesoderm. Between the gut and body wall


A body cavity that's not fully lined with tissue derived from mesoderm. Incomplete coelom


radially symmetrical animals having saclike bodies with only one opening and tentacles with stinging structures


in cnidarians, a stinging cell that is used to inject a toxin into prey


science dealing with the functions of living things

Surface-to-volume ratio

A relationship in which the volume of an object increases with the cube of the diameter, but the surface area increases with the square.


the vascular tissue through which food moves in some plants


the type of environment in which an organism or group normally lives or occurs

Passive Transport

transport of a substance across a cell membrane by diffusion

Active Transport

energy-requiring process that moves material across a cell membrane against a concentration difference

concentration gradient

the difference in the concentration of molecules across a distance

Interstitial Fluid

liquid found between the cells of the body that provides much of the liquid environment of the body


fluid portion of blood

Sensory Receptor

Cells or cell parts that detect stimuli. They then send signals to the brain


control center; determines the set point at which the variable is maintained; receives input from receptor; determines appropriate response


an organ (a gland or muscle) that becomes active in response to nerve impulses

Positive Feedback Mechanism

homeostatic control mechanism that increases the stimulus to push the variable farther from its originial value

Negative Feedback Mechanism

homeostatic control mechanism that reduces the output of the stimulus


a part of an organism consisting of an aggregate of cells having a similar structure and function


group of tissues that work together to perform closely related functions

Organ System

group of organs that work together to perform a specific function


Increase in number, size, and volume of a measured quantity


Series of stages in which specialized tissue organs, and organ systems form. Measured qualitatively


First layer of cells to form in the embryos of nearly all animals


Layers of cells covering internal or external surfaces. Arises from the ectoderm

Simple Epithelium

Epithelium that has cells that form a layer that is only one cell thick

Stratified Epithelium

Epithelium that has cells that form two or more layers

Pollen Grain

structure consisting of a few haploid cells surrounded by a thick protective wall that contains a male gametophyte of a seed plant


a functionally specialized substance (especially one that is not a waste) released from a gland or cell


the bodily process of discharging waste matter


organs in the body that secrete and manufacture materials for the body


Organ that removes urea, excess water, and other waste products from the blood and passes them to the ureter

Exocrine Gland

gland that releases its secretions through tubelike structures called ducts

Endocrine Gland

Gland that releases its secretions directly into the bloodstream

Adhering Junction

Cell junction composed of adhesion proteins anchors cells to each other or to extracellular matrix.

Tight Junction

a type of intercellular junction in animal cells that prevents the leakage of material between cells

Gap Junction

A type of intercellular junction in animal cells that allows the passage of material or current between cells.

Connective Tissue

tissue that holds organs in place and binds different parts of the body together


A generic connective tissue cell that produces fibers; the progenitor of all other connective tissue cell types.

Loose Connective Tissue

The most widespread connective tissue in the vertebrate body. It binds epithelia to underlying tissues and functions as packing material, holding organs in place.

Fibrous Irregular Connective Tissue

Strong, but flexible enough to allow movement
Reinforced by ligaments

Fibrous Regular Connective Tissue

bundles of collagen fibers with fibroblasts crowded between fibers forming tendons and ligaments, used for tensile strength


connects bone to bone


strong connective tissue that attaches muscle to bone


strong connective tissue that supports the body and is softer and more flexible than bone

Bone Tissue

Most rigid connective tissue, Internally supports body structures, very active tissue, heals much more rapidly than cartilage

Adipose Tissue

a kind of body tissue containing stored fat that serves as a source of energy

White Blood Cells

blood cells that rid the body of foreign microorganisms such as bacteria and viruses

Red Blood Cells

blood cells containing hemoglobin that carry oxygen through the bloodstream


tiny, disk-shaped bodies in the blood, important in blood clot formation

What three types of tissue do all vertebrates have?

skeletal, cardiac, and smooth muscle

Muscle Tissue

made up of many cells arranges in parallel with one another, in tight or loose arrays. coordinated contractions of layers or rings of muscles move the whole body or it's component parts

Skeletal Muscle Tissue

Striated, voluntary , more than one nucleus so lots of DNA to code for protein synthesis, functional partner of bone or cartilage

Cardiac Muscle Tissue

occurs only in the heart, where it constitutes the bulk of the heart walls; striated; not voluntary; contains sarcomeres


the basic contractile unit of striated muscle; the segment of a myofibril between two adjacent z-lines

Smooth Muscle Tissue

no striations and involuntary, found in walls of hollow visceral organs such as the stomach urinary bladder and respiratory packages, forces food and other substances through internal body channels

Nervous Tissue

tissue that receives messages from the body's external and internal environment, analyzes the data, and directs the response


a nerve cell; the basic building block of the nervous system


Chemical used by a neuron to transmit an impulse across a synapse to another cell


the junction between two neurons (axon-to-dendrite) or between a neuron and a muscle

sensory neuron

picks up stimuli from the internal or external environment and converts each stimulus into a nerve impulse to be delivered to the central nervous system


a nerve cell that relays messages between nerve cells, especially in the brain and spinal cord

Motor Neuron

nerve cell that carries signals from the central nervous system (brain/spinal cord) to muscle or gland cells

Central Nervous System

the portion of the vertebrate nervous system consisting of the brain and spinal cord

peripheral nervous system

the section of the nervous system lying outside the brain and spinal cord


bone forming cell


Mature bone cell


cell that functions in the breakdown and resorption of bone tissue

Red marrow

makes red blood cells. located in bones

Yellow marrow

gradually replaces red bone marrow in adult bones; functions as storage for fat tissue and is inactive in the formation of blood cells

What is the first skeleton to form in vertebrates made of?



Areas, of contact / near contact, between bones.


a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates

Intervertebral Disks

made of cartilage, separate and cushion the vertebrae from each other. Part of the spinal cord

Herniated Disk

the breaking apart of an intervertebral disk that results in pressure on spinal nerve roots


26 small bones that make up your backbone


the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body.


the extension of a neuron, long fiber that carries impulses away from the cell body of a neuron

trigger zone

where a nerve impulse is started

output zone

The part of a neuron, usually corresponding to the axon terminals, at which the cell sends information to another cell.


substance that triggers an immune response

Innate Immunity

immunity to disease that occurs as part of an individual's natural biologic makeup

Adaptive Immunity

(specific immunity) aquired ability to recognize and destroy a pathogen or its products. Requires exposure of the immune system to the pathogen


Large white blood cell that removes bacteria, foreign particles, and dead cells


White blood cell that releases enzymes


defend against bacterial/fungal infections, their activity and death in large numbers cause pus


any of various proteins secreted by cells of the immune system that serve to regulate the immune system


Type of white blood cell that produces antibodies that help destroy pathogens

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