Cicada

Phylum: Arthropoda
Class: Insecta

Body Structure: Cicadas go through a incomplete metamorphosis. Therefore, its nymph stage and adult stage does not differ drastically. On its adult stage, the cicada have 4 wings attached to their stout bodies. The wings when fully spanned, rages about 2.5cm to 15cm. When cicada is not using it, it rests at its back along side of the body. The wings colourless, and are supported with thin and firm veins that strengthens it. Adult cicadas all have 3 pairs, or 6 legs, just like all "insecta"s. They also have large compound eyes along with three small eyes called ocelli, that are mainly used for detecting predators from above. Adult cicada's antennae are small and setae-like, and is located just under the ocelli. For the mouth part of the adult cicada, it is enclosed in a long, thin, beak-like sheath. The sheath is called labium, and it consists of 4 fine, needle-like stylets that are used for feeding.

Respiration: The air enters through the spiracle, and from there, The tracheal tubes supply oxygen by diffusion to all body tissues.

Excretion: They use malpighian tubules to remove nitrogen-containing wastes from blood, concentrate them, and then add them to undigested food before it leaves through its anus. Also, in arthropods, and in cicadas, undigested food becomes solid waste that leaves through the anus.

Feeding: Cicadas are plant eaters. They eat by piercing the surface of plants with their mouth stylets. Then, they proceed onto sucking up the sap through a tube formed by the concave surfaces of two of the stylets.
However, because of this, Cicadas may prevent the growth of trees with the amounts of sap they drink.

Movement: The Cicada has wings that span 2.5 cm - 15 cm, as I mentioned above. They are EXTREMELY bad pilots though.


Circulatory System: Cicadas have an open circulatory system. This contributes to the fact that overtime, Cicada gets darker and darker in colour. It is known that not much blood flows to Cicada's legs as they remain hollow. This is the reason why Cicada stays so long in its upside down position.

Reproduction/ Life cycle: Usually, a young Cicada takes about 1~6 years of nymph form before becoming a full grown adult form. They hatch from its egg usually underground and spend their 6 years there. Afterwards, they come outside and grows wings to officially enter its adult stage. Contrary to their 1 to 6 years of nymph stage, they can only live up to few weeks in their adult form. While an adult, all male Cicada make sound in the operculum; which attracts females.The male and female adult cicadas mate and have fertilization internally. The male dies instantly, and the female dies shortly after laying its eggs.

Other Facts: CICADAS HAVE BILATERAL SYMMETRY, JUST LIKE ANY OTHER ARTHROPODS AND COMPLICATED ORGANISMS. They have 3 germ layers: ectoderm, endoderm, and mesoderm.

Cicadas are protosomes because during their 8-cell developement stage, they are spiral and determinate, their celom formation is schizocoelous, in other words, the ceoloms are solid mass of mesoderm split to form coelom, and their moouth develops from blastopore.

Interesting Facts - Singing of Cicadas Why&How?:

Singing:
The organs that cicadas use to make sound is called the tymbal. These are pair of membranes located in the abdomen, and the Cicada contracts and reliefs the muscle in order to make sound. When they contract the muscle, the membranes come inward, producing a sound. Note that Cicadas are the loudest and the only distinct sound makers, and scientists do not know how this process makes such a loud noise.

When Cicada sing, it is usually in the hot summer afternoon; they also stand still while singing. As I mentioned before, this singing attracts female Cicadas, and females are known to not sing.

Ecological Significance: Cicadas are part of a basic food chain

Squid DIEsection

           On this Thursday, I had fun dissecting a rather familiar invertebrate; the squid. Personally, I thought I knew a lot about squids. I eat them, cook them, roast them, and even eat them raw like sushi. As it turns out, all the squids that my family was buying all had been handled; I had never seen all those inside parts in my 10 years of squid handling experience. In otherwords, I was able to meet the objectives of this lab; locating and understanding the different functions of the squid.

Through this lab, I got to examine the external and internal organs of a squid. When I first learned about the phylum Mollusca, I was shocked to see a squid as one of them – I always thought the squid had soft, slimy bodies. However, when I was dissecting the internal of the squid, I was successfully able to figure out why even “cephalopods” are considered in the phylum Mollusca and why they are coined “head-foot”. Two of the biggest traits of the phylum Mollusca are that they have shells and a muscular foot. Internally, I was able to see a squid’s pen, a hard shell like structure that helps attach the squid’s organs. Externally, I was able to spot out that the muscular foot evolved to tentacles and arms to fit more suitably to their environment. Also, I was able to clearly see the squid’s eyes that are specially developed for hunting down prey.(My grandmother always used to eat it… yuck)

This lab was really helpful to me in two major ways. First, it obviously educated me to a new level of biological experience. However, secondly, through this lab I realized that even a tasty and weird looking creature like a squid has fascinating, and an organized structure. I personally think “dissection” labs are one of the best types of lab that I have ever had. I really hope to do more in future.       

1. A squid has 2 arms, and 8 tentacles

(Credits to Alan Zhong)
2. A squid's arm and tentacles function differ.
A squid's tentacle has suckers attached to it which
captures prey, and a squid's arm makes sure the prey
cannot escape

3. The energy force of the squid is called "jet propulsion"
The squid will move away from the force. Hence "water
goes this way" and "squid goes this way"

4. There are two external features that are adaptations for squid's
predatory life. These are the Eyes of the squid and the Tentacles
and Arms of the squid. The eyes of a squid is highly developed
for spotting and for hunting prey, and the arms&tentacles of a
squid are essential for a squid as both parts are extremely
well-suited for hunting prey.

5. The two general traits of molluscs were the
Visceral Mass, and the Feet that evolved from
the normal foot of a mollusc.

1. A squid has 1 pair of gills, a total number
of two.

2. The ink sac empties into the water, which
is primarily used for disrupting, and surprising
a prey or a predator.

3. The function of a squid's pen is to hold together
the muscles of a squid. 

4. I think that the wastes exit the squid through
the squid's anus. 

Earthworm DIEsection Lab

I consider myself as a "man". However, when we were dissecting earthworms on this Friday, I was hesitant to state myself that. Before I get into details about the dissection of the worm, I'd like to say that this lab was simply amazing. Through this lab, I could vividly see, almost touch the worm parts and their organs, and this helped me understand the whole Phylum Annelida to a whole new level. For example, now I have a clear idea what a true coelom is. Before, I had to just had to nod my head with the vague description given: "body cavity which allow them to have true organ systems and muscular layers". Now I know that earthworms have true coelom, just like humans. Another great thing about this lab was, I got to see not only the outside parts of the worm, but see all the inside and guts of the worms. The digestive tube of the worm looked like a long trail of black ink. The digestive system of the worm was interesting to look at because not only the tube connects the mouth and the anus, it also was very dirt-like. The hearts, however, looked completely different and, out of the ordinary. In fact, there were five of them. The heart, otherwise known as the aortic arches, pump blood through the worm's body.

In retrospect, I understand why this lab was done - to observe how an earthworm's structures of earthworm anatomy. At that time, I was busy freaking out and having a great time by observing a worm's internal organs. In the lab, I followed the instructions on the hand-out carefully, and proceeded to dissect the whole worm. However, I was pretty messy with the surgery; I am pretty sure I squished an organ here and there. Overall, I think this lab has really stepped up my knowledge in the Phylum Annelida. I'd give it 10/10.

Responses

1. The name of the pumping organs of an earthworm is
called the "Aortic Arches" or, the hearts

2. The food passes through the Mouth, pharynx, esophagus,
crop, gizzard, and intestine. (in order)

3. The parts that serve as an earthworm's brain are the ventral nerve cord,
because its brain and the cords are attached together, and travels
throughout the length of the worm.

4. The parts of the worm's body that were included in the
excretory system, that I got to observe was the Nephridia
and the anus (not labelled on photo). The anus is located at the opposite end of the head of the worm. 

5. One can conclude that a particular earthworm eats soil
by observing the black intestine of the worm.

CREDIT: http://www.angelfire.com/ny4/sci7/Setae.jpg
6. An earthworm's seatae make it well adapted to its habitat by  helping
earthworms anchor into the soil while burrowing, digging, and moving
around in the dirt. Without this adaptation, the worms will have much
harder time trying to squiggle. (LOCOMOTION)

CREDIT: #2 OF MY QUESTION
7. The earthworm's digestive system is adapted for extracting relatively small
amounts of food from large amounts of ingested soil by digesting the dirt
through its long intestine. Also, the gizzard breaks the food down, completing
an unending "digestive cycle"

8. The reason that our dissection did not go beyond segment 32 is because
it is disgusting, and all the juicy stuff is located at the anterior part of the worm.
As we dissect down, we will possibly able to spot the liquid substances that 
the worm ate.

Earthworms fertilize by sexually mating. During this process,  two
worms line up opposite to one another, and exchange sperm. The Citellium
forms a slime tube. As the worm moves through it, it will pick up female pore,
eggs. The tube will continue to move down the earthworm and pass over
the male pore called the spermatheca which has the stored sperm
called the spermatozoa. Finally, the slime tube will close out, and forms an
egg cocoon that will be placed in the soil.