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Natural sciences

Ecosystems and the environmental balance

Educator section







Leaner section


Activity: to understand how animals and insects differ with regard to reproduction/life cycle [lo 2.3]

(i) Animals also differ with regard to their reproduction

Some young look just like the adults when they are born, while others first need to undergo a metamorphosis (change) before they look like the adults. Some animals undergo an incomplete metamorphosis, while others undergo a complete metamorphosis. A complete metamorphosis consists of the following stages: eggs are laid; larvae hatch; then they develop into pupae from which the adults finally develop.

Insects: fruit flies

Fruit flies belong to the Drosophila family and are used extensively as laboratory flies with which experiments are done. In nature, these flies sometimes cause extensive damage in fruit orchards if they are not combated early enough.

Adult fruit flies lay their eggs in the skin of the fruit, which then rot quickly and fall from the trees. The rotting fruit pulp is the source of food for the larvae that hatch. After a few days, the larvae crawl into the ground and change into a pupae. The mature fly appears from the pupa after about two to three weeks.

In order to combat the fruit fly, it is necessary to treat both the adult fly that contaminates the fruit in the trees as well as the soil under the trees, in which the pupae are, with pesticides.

Each female can lay 15 to 50 eggs per day and up to 900 eggs in a lifetime. The entire life cycle of the fruit fly lasts about two weeks. Before mating takes place, the male fly first needs to court the female. The female will accept him only if he is an adult and from the same species that she is. The female recognises a male from the same species by means of her senses of sight, hearing and smell.

Assignment 9

The following sketch represents the life cycle of the fruit fly, but in the incorrect sequence. Place it in the correct sequence and then draw your own sketch of the complete metamorphosis of the fruit fly.

Group assessment

CRITERIA 1 2 3 4
Correct sequence ______ ______ ______ ______
Creative representation ______ ______ ______ ______
Sketches/illustrations in proportion ______ ______ ______ ______
Captions ______ ______ ______ ______


Learning Outcome 2: The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

Assessment Standard 2.3: We know this when the learner interprets information.

Questions & Answers

what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
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Source:  OpenStax, Natural sciences grade 6. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11079/1.1
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