BISC 208 Exam 2 Study Guide

These flashcards cover key vocabulary from BISC 208 Exam 2 topics including plant structure, animal development, tissues, and the nervous system.

Photoautotrophs

Organisms that produce their own food using light energy.

Indeterminate growth

Growth that continues throughout the organism's life.

Cell migration

The movement of cells from one location to another during development.

Hormones

Chemical messengers that regulate physiological processes.

Cell lineage

The developmental history of a cell as it divides and differentiates.

Shoot apical meristem

Region in plants where growth occurs at the tip of the shoot.

Root apical meristem

Region in plants where growth occurs at the tip of the root.

Dermal tissue

The outer protective layer of plant organs.

Vascular tissue

Tissue responsible for the transport of water and nutrients in plants.

Ground tissue

Tissue that makes up the bulk of a plant, involved in photosynthesis and storage.

Polarity

The orientation of the plant axis being unequally divided during development.

Radial symmetry

Symmetry around a central axis, as seen in many flowers.

Bilateral symmetry

Symmetry where only one plane divides the organism into two equal halves.

Surface area:volume ratio

A measure that affects the rate of exchange of materials with the environment.

Phenotypic plasticity

The ability of an organism to change its phenotype in response to environmental changes.

Chloroplast

An organelle in plant cells that conducts photosynthesis.

Vacuole

A storage organelle in plant cells that maintains turgor pressure.

Plasmodesmata

Microscopic channels that allow for transport and communication between plant cells.

Xylem

The vascular tissue responsible for water transport in plants.

Phloem

The vascular tissue responsible for the transport of sugars and nutrients in plants.

Tracheids

Long water-conducting cells found in the xylem of vascular plants.

Vessel elements

Shorter, wider water-conducting cells in the xylem that facilitate flow.

Pits

Regions in the cell walls of tracheids allowing water movement between cells.

Apoptosis

Programmed cell death, a normal part of development.

Transpiration

The process of water vapor loss from the plant to the atmosphere.

Sieve-tube element

A type of phloem cell that transports sugars.

Companion cell

A specialized phloem cell that assists sieve-tube elements.

Sap

The fluid that flows through the xylem and phloem of plants.

Metazoa

A major group that includes all animals.

Monophyletic

An ancestor and all its descendants in a clade.

Colonial flagellated protist

An early descendant of protists thought to be ancestral to animals.

Phyla

The plural of phylum, a taxonomic ranking.

Choanoflagellate

Single-celled organisms that are the closest living relatives of animals.

Heterotroph

Organisms that obtain organic food molecules by eating other organisms.

Gap junctions

Specialized intercellular connections that facilitate cell communication.

Sexual reproduction

Reproduction involving the fusion of male and female gametes.

Body symmetry

The arrangement of body structures in the organism.

Embryonic cell layers (germ layers)

The three layers (endoderm, mesoderm, ectoderm) that form during embryonic development.

Body cavity

A fluid-filled space within the organism that contains organs.

Embryonic development

The process by which the embryo forms and develops.

Parazoa

Animals lacking true tissues, such as sponges.

Eumetazoa

Animals with true tissues.

Radially symmetrical

Organisms that can be divided into similar halves by multiple planes.

Bilaterally symmetrical

Organisms that can be divided into similar halves by only one plane.

Diploblastic

Organisms with two embryonic germ layers.

Endoderm

The innermost germ layer that develops into internal organs.

Ectoderm

The outermost germ layer that forms the skin and nervous system.

Triploblastic

Organisms with three germ layers: ectoderm, mesoderm, and endoderm.

Gastrulation

The process during embryonic development that forms the three germ layers.

Coelom

A body cavity lined with mesoderm.

Bilaterians

Animals with bilateral symmetry.

Acoelomate

Animals lacking a coelom.

Pseudocoelomates

Animals with a body cavity that is not completely lined with mesoderm.

Coelomates

Animals with a true coelom lined with mesoderm.

Spiral cleavage

A type of embryonic development seen in some protostomes.

Protostomes

Animals in which the mouth forms before the anus during development.

Determinate cleavage

Embryonic development where the fate of each cell is determined early.

Radial cleavage

Embryonic development in which cells are arranged radially.

Indeterminate cleavage

Development where cells can develop into complete embryos.

Pluripotent

Cells that can give rise to multiple cell types.

Blastopore

The opening that forms during early embryonic development.

Anus

The opening at the opposite end of the blastopore in deuterostomes.

Exoskeleton

A hard external structure that provides support and protection.

Notochord

A flexible rod that provides support in the embryonic stage of chordates.

Vertebral column

The backbone of vertebrates.

Segmentation

The division of the body into repeated segments.

Porifera

The phylum of sponges.

Cnidaria

The phylum that includes jellyfish, corals, and sea anemones.

Ctenophora

The phylum of comb jellies.

Radiata

Animals that exhibit radial symmetry.

Bilateria

Animals that exhibit bilateral symmetry.

Protostomia

The group of animals that includes protostomes.

Deuterostomia

The group of animals that includes deuterostomes.

Lophotrochozoans

A group of protostomes that includes molluscs and annelids.

Ecdysozoans

A group of protostomes known for molting.

Flatworms

Acoelomate worms that belong to the phylum Platyhelminthes.

Rotifers

Microscopic animals with a crown of cilia.

Lophophorates

Aquatic animals with a lophophore.

Molluscs

A diverse group of animals that includes snails and octopuses.

Annelids

Segmented worms.

Nematodes

Roundworms.

Arthropods

Invertebrates with jointed legs, including insects and crustaceans.

Echinoderms

Marine animals with radial symmetry, such as starfish.

Chordates

Animals with a notochord at some stage of development.

Sessile

Organisms that are anchored in place and do not move.

Gastrovascular cavity

A digestive cavity with a single opening.

Lophophore

A feeding structure found in some lophophorates.

Trochophore

A larval form common to certain groups of animals.

Open circulatory system

A system where blood is not always contained within vessels.

Ecdysis

The process of shedding exoskeletons.

Parasitic

Living on or in another organism and deriving nutrients at its expense.

Neurons

Specialized cells that transmit nerve impulses.

Nervous system

The organ system that coordinates responses to internal and external stimuli.

Dendrites

Extensions of neurons that receive signals.

Cell body

Contains the nucleus and organelles of a neuron.

Axon

The long projection that transmits impulses away from the cell body.

Axon terminus/termini

The end of the axon where neurotransmitters are released.

Phospholipid bilayers

Layers of phospholipid molecules that form cell membranes.

Resting potential

The electrical potential of a neuron at rest.

Electrochemical gradient

The difference in charge and concentration across a membrane.