BIS 2C Lab Practical

rooted phylogenetic tree

tree that has a root node; more rooted trees than unrooted statistically; specify evolutionary relationships with completeness

unrooted phylogenetic tree

tree that lacks root node; helpful because there are less unrooted trees than rooted ones statistically; does not entirely specify evolutionary relationships, but adds constraints

sister group

pair of taxa originating from same lineage split; most closely related; arise at same time

clade

synonym for monophyletic group

homology

Similarity in characteristics resulting from a shared ancestry.

homoplasy

similar characters caused by convergent evolution, not shared ancestry

convergent evolution

Process by which unrelated organisms independently evolve similarities when adapting to similar environments

outgroup

at least one taxa that is as closely related as possible to ingroup species without actually being part of the ingroup; used as a reference and to help tree rooting

congruence

characters support hypothesized tree

conflict

characcters do not support hypothesized tree

polytomy

a branch point from which more than two descendant groups emerge

soft = b/c missing data

hard = fast speciation, have data but unlikely to be resolved

coccus

A spherical bacterium.

bacillus

rod-shaped bacterium

helical

elongate spiral bacterium

lateral gene transfer

unidirectional sharing of small portions of genomes between bacteria that product via binary fission. Can create big effects from small, non-sexual transfers.

LUCA

Last Universal Common Ancestor. The shared ancestor that all life diverged from

microbiome

all of the microorganisms that live in a particular environment, such as a human body

haplontic (n)

describes a life cycle in which the haploid stage is the dominant stage

diplontic (2n)

describes a life cycle in which the diploid stage is the dominant stage

alternation of generations

the alternation between the haploid gametophyte and the diploid sporophyte in a plant's life cycle

gametophyte

Haploid, or gamete-producing, phase of an organism

sporophyte

Diploid, or spore-producing, phase of an organism

archegonia

female gametangia

antheridia

male gametangia

gametangia

A reproductive organ that houses and protects the gametes of a plant

sporangium

spore capsule in which haploid spores are produced by meiosis

spore

A reproductive cell with a hard, protective coating sporopollenin. Haploid

sori

raised spots located on the underside of sporophyte ferns, clusters of sporangia

vascular tissue

Plant tissue consisting of cells joined into tubes that transport water and nutrients throughout the plant body.

xylem

vascular tissue that carries water upward from the roots to every part of a plant. In a tree, makes up wood

pholem

the vascular tissue in plants that conducts sugars and other metabolic products downward from the leaves. Becomes bark in trees

tracheid vessel element

water-conducting cells of the xylem

waxy cuticle

Forms a waterproof layer to stop water loss due to photosynthesis/evaporation

dominance

A characteristic in which an allele that expresses its phenotype even in the presence of a recessive allele. either sporophyte or gametophyte usually mostly expressed

independence

sporophyte and gametophyte do not depend on one another to survive. Seen in ferns

stem

supporting structure that connects roots and leaves and carries water and nutrients between them. indeterminate growth

leaf

the main organ of photosynthesis and transpiration in higher plants. determinate growth, all consistent with one another in a plant

root

An organ in vascular plants that anchors the plant and enables it to absorb water and minerals from the soil.

megaphyll

A leaf with a highly branched vascular system, characteristic of the vast majority of vascular plants. Overtopping, planation (flattening), webbing.

microphyll

A small, usually spine-shaped leaf supported by a single strand of vascular tissue, found only in lycophytes.

nodes

where leaves grow from

determinate growth

some plant organs cease to grow at a certain size

indeterminate growth

A type of growth characteristic of plants, in which the organism continues to grow as long as it lives.

bifacial vascular cambium

A way to produce more vascular tissue and thicker stems; it is a type of meristem that continues to divide and produce new vascular cells and tissues on two sides

turgor pressure

The pressure that water molecules exert against the cell wall

diffusion (osmosis)

Movement of molecules from an area of higher concentration to an area of lower concentration.

evapotranspiration

water evaporates from leaves, causing soil water to be pulled into xylem and carried up to all parts of plant

sporophyll

A modified leaf that bears sporangia and hence is specialized for reproduction.

strobilus

compact cluster of spore-bearing structures in some seedless vascular plant sporophytes. CONE!

homospory

production of a single type of spore

heterospory

production of two different types of spores

nutritive tissue

in seed plants: tissue surrounding egg in archegonia that nouishes seed

endosperm

In angiosperms, a nutrient-rich tissue formed by the union of a sperm with two polar nuclei during double fertilization. Provides nourishment to the developing embryo in angiosperm seeds. TRIPLOID

seed integument

part of ovule. Tissue layers surrounding megasporangium

seed coat

A tough outer covering of a seed, formed from the outer coat of an ovule (integuments)

plant embryo

the early, undeveloped stage of a new plant

cotyledon

first leaf or first pair of leaves produced by the embryo of a seed plant

monosulcate

having one long furrow; typically describes type of pollen

tricolpate

having three pores; typically describes type of pollen

petal

A modified leaf of a flowering plant; petals are the often colorful parts of a flower that advertise it to insects and other pollinators.

stamen

the male reproductive organ of a flower

anther

the part of a stamen that contains the pollen.

filament

Supports the anther

pistill

female reproductive organ of a flower

stigma - plant

sticky portion at the top of the style where pollen grains frequently land

style

The stalk of a flower's carpel, with the ovary at the base and the stigma at the top.

ovary

In flowers, the portion of a carpel in which the egg-containing ovules develop. Ovary usually results in fruit

ovule

A structure that develops within the ovary of a seed plant and contains the female gametophyte.

trichome

hairlike projections that extend from a plant's epidermis; help reduce water evaporation and may provide protection from herbivores

pangaea

The name of the single landmass that broke apart 200 million years ago and gave rise to today's continents

hyphae

The branching, threadlike tubes that make up the bodies of multicellular fungi

mycelium

densely branched network of the hyphae of a fungus

fruiting body

The reproductive structure of a fungus that contains many hyphae and produces spores

dikaryon

hyphae with cells having 2 different nuclei in each cell.

septate

hyphae with cross walls

aseptate

hyphae that have no cross-walls and are multinucleate

ascus

vertical, sac-like strucures containing 8 ascospores. Characteristic of ascomycota

ascocarp

fruiting body of ascomycetes made of several asci

basidium

Club-shaped, reproductive structure in which club fungi produce 4 external basidiospores. Characteristic of basidiomycota

basiocarp

Fruiting body of basidiomycota. Made of a stalk called the stripe and a flattened cap with gills called Basidia underneath.

blastula

hollow ball of cells

gastrula

In animal development, a series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a three-layered embryo, the gastrula.

ectoderm

outermost germ layer; produces sense organs, nerves, and outer layer of skin

endoderm

the inner germ layer that develops into the lining of the digestive and respiratory systems

mesoderm

middle germ layer; develops into muscles, and much of the circulatory, reproductive, skeletal, and excretory systems

blastopore

the opening of the central cavity of an embryo in the early stage of development.

complete gut

two openings, a mouth an and anus. One-way

incomplete gut

gut has a single opening rather than a separate mouth and anus. Blind, two-way gut.

acoelomate

an animal that lacks a coelom, or body cavity

pseudocoelomate

An animal whose body cavity is not completely lined by mesoderm

coelomate

An animal that possesses a true coelom (a body cavity lined by tissue completely derived from mesoderm).

radial symmetry

The quality of having many lines of symmetry that all pass through a central point.

pentaradial symmetry

circular body plan that can be divided into 5 equal parts

bilateral symmetry

Body plan in which only a single, imaginary line can divide the body into two equal halves.

asymmetrical

no symmetry

spicule

a needle of silica or calcium carbonate in the skeleton of some sponges. Morphology can be characteristic of species

choanocytes (collar cells)

a flagellated cell with a collar of protoplasm at the base of the flagellum, numbers of which line the internal chambers of sponges.

cnidocytes

Special stinging structures on cnidarians that look like small harpoons.

nematocysts

specialized organelles within cnidocytes that eject a stinging thread

polyp

The sessile, tubular form of a cnidarian with a mouth and tentacles at one end and a basal disk at the other