Plant Form and Function
Plant Form and Function
Tissue is a group of cells with a common function, structure, or both
Organ consists of several types of tissues that together carry out particular functions
HIERARCHY OF CELLS, TISSUES, AND ORGANS IN PLANTS
Root is an organ that anchor a vascular plant (usually in the soil) absorbs minerals and water, and often stores organic nutrients
Dicots and gymnosperms have taproot system consisting of one main vertical root (tap root)
THREE BASIC PLANT ORGANSROOTS, STEM, AND LEAVES
Tap roots give rise to lateral roots also called branch roots Root crops such as carrots, turnips are harvested before they flower Fibrous root system a mat of generally thin roots spreading out below the soil surface, with no root standing out ax the main one
THREE BASIC PLANT ORGANSROOTS
Adventitious is the root arising from the stem (adventicus, extraneous)
any plant part that grows in an unusual location
fibrous root system is usually shallower than tap root
root hair is an extension of a root epidermal (protective cell on a plant surface)
Some modified roots provide more support and anchorage while others store water and nutrients.
ROOT
is an organ consisting of nodes, the points at which leaves are attached
internodes are the stem segments between nodes
axillary bud a structure that has a potential to form a lateral shoot commonly called a branch
STEMS
main photosynthetic organ of most vascular plants consist of the following
flattened blade and a stalk petiole which joins the leaf to a
node of the stem Monocot and dicot differ in the
arrangement of veins in the first one it has a parallel major veins unlike the previous one which has a multibranched network of major veins
LEAVES
Dermal tissue
Vascular tissue
Ground tissue
THREE TISSUE SYSTEM
outer protective covering in nonwoody plants, the dermal tissue usually consists of a single layer of tightly packed cells called the epidermis
in woody plants, protective tissues known as periderm replace the epidermis in the epidermis of leaves and most of stems a waxy coating called cuticle helps to prevent water loss
DERMAL TISSUE SYSTEM
carries out long-distance transport of materials between roots and shoots two vascular tissues are xylem and phloem Xylem conveys water and dissolved minerals upward from roots into the shoots Phloem transports organic nutrients such as sugars from where they are made to where they are needed
VASCULAR TISSUE SYSTEM
ground tissue that is internal to the vascular tissue is called pith
ground tissue that is external to the vascular tissue is called cortex
more than just filler includes various cells specialized for functions such as storage, photosynthesis and support.
GROUND TISSUE SYSTEM
Animal Form and Function
“weave”are group of cells with a common structure and function classified into 4 different categories
Muscle tissue Nervous tissue Connective tissue Epithelial
TISSUE STRUCTURE AND FUNCTION
occurring in sheets of tightly packed cells.
covers the outside of the body and lines organs and cavities within the body
this tight packing enables the epithelium to function as barrier against mechanical injury, microbes, and fluid loss
EPITHELIAL TISSUE
simple epithelium has a single layer of cells
stratified epithelium has multiple tiers of cells pseudostratified epithelium is a single- leayered but appears stratified because the cells vary in in length
EPITHELIAL TISSUEAS TO NUMBER OF CELLS
cuboidal like dice
Columnar like bricks standing on end
squamous like floor tiles
EPITHELIAL TISSUEAS TO NUMBER OF CELLS
it functions are to mainly bind and support other tissues
Connective tissue fiber, which are made of protein are of three kinds
Collagenous fiber Elastic fiber reticular fiber
CONNECTIVE TISSUE
are made of collagen most abundant protein in animal kingdom
nonelastic and do not tear easliy when pulled lengthwise
example: skin at the back of you hand
COLLAGENOUS FIBERS
are long threads made of a protein called elastin
it provides a rubbery quality that complements the nonelastic strength of collagenous fibers
ex, when you release the skin on the back of your hand
ELASTIC FIBERS
is composed of long cells called muscle fibers that are capable of contracting, usually when stimulated by nerve signals
Most abundant tissue in most animals, and muscle contraction accounts for much of the energy-consuming cellula work in active animal
MUSCLE TISSUE
senses stimuli and transmits signals in the form of nerve impulses from one part of the animals to another
functional state of nervous is neuron or nerve cell, which is uniquely specialized to transmit nerve impulses
NERVOUS TISSUE
moderate changes in internal environment any homeostatic control system has three functional components
receptor detects a change in some variable such as change in body temperature control center processes information it receives directs an appropriate response by the effector
MECHANISM OF HOMEOSTASIS
a process by which animal maintains an internal temperature with tolerable range
this ability to change is critical to survival because most biochemical and physiological processes are vey sensitive to changes in body temperature
THERMOREGULATION