Bio 2 lab practical 1

Chapter 1,2,3

Taxa

Hierarchal class system based on a tier of seven encompassing groups from largest to smallest

Taxa groups

kingdom

Phylum

Class

order

family

genus

species

Species

A group of individuals which are capable of interbreeding and producing fertile offspring (donkey and horse are considered different species)

Genus

Similar species that are closely related but do not interbreed

Family

Similar genre are grouped into families

Systematics

based on degree of similarity between organisms across morphology, physiology, genetics, cytology, biochemistry, behavior, and ecology

Monophyletic Taxon

All members of a taxon evolved from a common ancestor

Cladograms

evolutionary phylogenetic trees based on similar DNA sequences (genomes) of the organism in question

Domaine

A super kingdom (Eukarya, Bacteria, Archea)

Embryophytes

All terrestrial plants that develop a multicellular organism

Angiosperms

Flowering plants. the most varied widespread terrestrial plant form.

Dicotyledonae (dicotes)

contain two cotyledons in their seed (sunflowers, lima beans, buttercup, and basswood)

Monocotyledonae (monocots)

contain one cotyledons in their seeds (corn, tulips, lilies, palms)

Dicot vs monocot

Dicot vs Monocot examples

Stem

A structural support and framework for the plant, distinguished by nodes. The region between the nodes is known as the internode.

Leaves

the main photosynthetic part of the plant, composed of the blade (flattened portion) which is attached to the petiole, the stalk arising from the stem.

Buds

a) axial buds - have the potential to form vegetative branches

b) Terminal buds - develop leaves, nodes, and internodes

Flowers

Reproductive structure resulting from the transformation of a vegetative meristem to a floral meristem, capable of developing male and female gamatesl

Dermal

single layer of tightly packed cells covering the exterior of young plants. protective and absorptive interface with the environment and watertight barrier.

Vascular

A system of two distinct tissues:

a) xylem - a tissue made up of several cells that conduct water and dissolved solutes from the roots to the leaves.

b) Phloem - a tissue that transports the products of photosynthesis to nonphotosynthetic parts of the plant. Can transport up and down. unlike xylem.

Ground

serves as structure for the plant, photosynthesis, and storage of its products.

Epidermis (root)

forms the protective covering of the plant, single cell layer of dermal tissue for water and mineral absorption.

Cortex (root)

large region of ground tissue adjacent to the epidermis. made up of loosely packed parenchyma cells.

parenchyma cells (root)

major site of metabolic activity within the plant contain starch-storing bodies called plastids.

endodermis (root)

actas as a selective barrier that regulates the passage of minerals from cortex into the vascular tissue.

Stele (root)

central core of the dicot root.

Pericycle (root)

a single layer of cells underlying the endodermis with potential meristematic activity, giving rise to lateral roots which connect the vacular tissue of the stele creating a path for the conduction of water and minerals to the aerial body of the plant.

Xylem (root)

Star-shaped bundle of large, hollow cells at the center of the stele. Composed of tracheid and vessel elements cells, which form pipes once they mature and die serving for water conducting.

Phloem (root)

consists of two primary cells

a) sieve-tube members - no organelles. serve as conduits for the biderectional movement of organic material

b) companion cells - do not conduct materials, supoort the activities of the sieve-tube

Pith (root)

Located in the monocot, forming a ring around central mass of parenchyma cells.

root cap (root)

region of zone of loosely packed cells within the extreme tip of the root.

apical meristem (root)

region of zone of tightly packed cells within the zone of cell division.

zone of enlogation (root)

region behind the apical meristem containing cells whose length increase, forcing the root tip forward.

root hairs (root)

epidermal cells stemming from the roots to increase the area of nutrients absorption.

Vascular bundles (stem)

dicots- form a ring within the ground tissue separating the cortex from the pith. Thin-walled parenchyma cells serve to store nutrients, also store water to maintain erection.

Rays

radial rows of parenchyma cells, lie between the bundles in the ring of vascular tissue connecting the pith and cortex.

Vascular cambium

cells of the cambium layer fused with adjacent bundles composing a continuous ring of dividing cells.

Annual rings

xylem cells that form in the spring of the year, and goes dormant in the winter with no growth. primary growth at the farthest point.

Periderm

layers of cork and cambium creating a was-like material increasing resistance and decreasing permability.

bark

cell layers, living and dead, including secondary phloem and layers of periderm outside the vascular cambium.

Upper/lower epidermis

outermost layers on the top and bottom of the leaf. Composed of packed cells that resist damage and disease.

mesophyll

cells between upper/lower epidermis.

Stomata

Small pores on the epidermis, allows for gas exchange between cells of the mesophyll and the external air.

Cuticle

nonliving, waxy layer that retards water loss and covers the outer walls of these cells.

guard cells

modified epidermal cells whose change in shape regulate the size of the stoma opening.

palisade parenchyma

upper layer within the mesophyll of evenly spaced cylindrical cells whose axes are perpendicular to the layer of epidermis above. most photosynthesis occurs in these cells containing more chloroplasts than its lower part.

Spongy parenchyma

more open zone of irregularly spaced cells with relatively large spaces in between. Space allows for fast gas exchange in the leaf.

Veins

vascular bundles of the leaf that cross the mesophyll and are continuous with those of the stem.