Objectives:Students are able to: Distinguish growth and development Explain factors that influence growth and development in plants Explain factors that influence growth and development in animals Compare metamorphosis and metagenesis
Growth and development areprocess in which the bothsimultaneously.Growth and development areinseparable
Growth is the process of size increasewhich is irreversible (cannot back tothe origin).It is caused by number of cellsincrement and cells size incrementGrowth has quantitative property (canbe measured)Example: Height, weight.
Development is process of becoming matureDevelopment has qualitative property(cannot be measured)Example:• production of flowers in plant• The change of seed to a sprout• Hen lay eggs
Growth and development in plantsGrowth in plants happen in meristematicregion, that is in the tip of stem, the tip ofroot and cambium.Growth in the plant can be measured byusing AUKSANOMETER
There are two kinds of growth in plants,primary growth and secondary growth.Primary growth is the increment of lengthsize in the part of plant’s stem.The Primary growth is caused by thepresence of activity of primary meristemtissue (apical meristem) that found in theedge of stem and the edge of root.The Primary growth makes stem and roothigher and longer
Secondary growth is the increment of size orthickness of a plant body.It is caused by the activity of secondarymeristem tissue, that is fellogen in stemcambium and root.The Secondary growth causes theenlargement of stem diameter.
Factors that influence growth and development in plantsGrowth and development in plants are influencedby internal factors and external factors.1. Internal factors Internal factors are factors that come frominside of the body of organisms themselves.They are gene and hormone. a. Gene Gene is a carrier of genetic factors that will be derived to its descendant. It doesn’t appear from outside.
b. Hormone Plant hormone is an organic compound which is made in a part of plant, then bring to other part of plant. Plant hormone is called phytohormone. For example: Auxin (IAA)Auxin causes the increases the number and size of thecells and causes the tree to become taller Giberelin Giberelin race growth of sprout. Sitokinin Absisat acid Etilen
2. External factors External factors are factors that come fromoutside of the body of organisms. Some external factors are: Food (nutrition) Food is main factor for growth and development o the organisms. Foods change to be energy for growth and development Water The body of organisms consists mostly ofwater. Water is the solvent (the substance thatdissolves various other substances). Water is raw material for photosynthesis.
Light Green plants need sunlight to support photosynthesis process. Light also stimulate the chlorophyl formation. Temperature All organisms need certain temperature for their life. The temperature change can influences growth, photosynthesis, reproduction, respiration, and transpiration in plants. Oxygen Oxygen need for respiration in plants Humidity The humidity influences vaporization process in plants
Growth and development in animalsThe growth and development of animalshappens in all parts of its body.The growth and development of animalcommonly begun from fertilizationprocess.Growth and development of animal can beseen from three phases, those are: Fission (cleavage) Gastrulation Organogenesis
Fission is a fission process of zygote to be celldescendant which happens by mitosis.The first fission begun from one to be two, two to befour, four to be eight, eight to be sixteen, sixteen to bethirty-two, and so on. Then cells fission continueforming morula and blastula. Cleavage in frog and human
Gastrulation is the process of arranging andregulating of cells into different layers.In gastrulation, it happens the formation ofgastrosol (arkenteron) then which will beform intestine.In gastrulation phase formed three layer,ectoderm (external layer), mesoderm(middle layer), and endoderm (inner layer).Organogenesis is the process of formationof organs and organs system.
Ectoderm layer forms nerves system,skin, eyes, nose, ears, hair, nail, andmedula adrenal.Mesoderm layer forms muscle, bone,blood vessel, kidney, connective tissue,ureter, testis, ovarium, uterus and limfesystem.Endoderm layer forms faring,esophagus, stomach, intestine, lever,pancreas, trachea, and lung.
Factors that influence growth anddevelopment in animalsGrowth and development in animals are alsoinfluenced by internal factors and external factors.1. Internal factors a. Gene Gene is a carrier of genetic factors that will be derived to its descendant. It doesn’t appear from outside. b. Hormone Hormones are made in endocrine glands. Some hormones which influence growth and development are somatotrophin, tiroxin, and gonadotrophin, testosterone, and estrogen.
2. External factors Some external factors are: Food (nutrition) Water Light Temperature Oxygen.
Imperfect metamorphosis in grasshopperThe size of grasshopper nymphs is smaller than adult grasshoppersand they are wingless; but on the whole they are the same as adultgrasshoppers in shape
The phases of perfect metamorphosis are:egg larva pupa imagoSome animals that experience perfectmetamorphosis are:butterfly, bee, house fly, ant, beetle.egg At a certain moment a larva becomes inactive and changes into a pupa. In this phase there appears a soft skin that forms a completely wrapping tissue. Then, the pupa hanges into an adult butterfly, in a completely different shape.
b. Metamorphosis in frogA frog starts its life cycle as a zygote in a fertilized egg. Theegg then hatches and a tadpole comes out. A tadpole isable to swim to small plants to find food. It continues togrow and then change in shape. The growth starts withlimbs (or legs), lungs, and teeth that grow inside the mouth.Changes that will support the tadpole’s life on land beginat this time. After a few months the body of the youngfrog has completed its metamorphosis process.
Metamorphosis is the change in an organism in one life cycle. When themetamorphosis is completed, the animal gains its adult shape. The pattern of change is complete and the cycle may occur in any new individual of the species.
METAGENESISMetagenesis is rotating descendant (life cycle)between sexual phase and asexual phase.In one life cycle of organisms which experiencemetagenesis, there are two different phases.In plants, one phase, spores are produced. Inthe other phase, sexual cells or gametes areproduced. The spore-producing phase iscalled the sporophyte phase, and the gamete-producing phase is called the gametophytephase.Some organism that experience metagenesisare Moss, Fern and Jelly fish (Aurelia).
Metagenesis in Moss Spore Protonema Moss plant Gametophyte generation Antheridium Arkegonium Zygote Sporangium Sporophyte generationThe moss plants you are observingare members of a gamethophyte generation.Sporangium is members of a sporophyte generation
When you observe fern plants, you will seethat there are groups of sporangia on thelower surface of the leaves. It means that theplant is in the sporophyte stage. The fernplants you are observing are members of asporophyte generation. If the spores in thesporangia fall on a moist place, each willgrow and flatten into a heart-shapedstructure with ribbon-like roots calledprothallium, which will produce male andfemale gametes. Prothallium are membersof a gamethophyte generation.
Jelly fish is one of invertebrate which is live inthe sea. In their life, cycle jelly fish experiencedescendant rotation, polyp phase when theylive in the ground sea and medusa phasewhen they swim.Polyp is member of a vegetative generation,which reproduce by budding.Medusa is member of generative generation,which reproduce by produce gametes.