Biology Essay, Research Paper


1. The virus is made up of five parts and is in the size range of 10

nm-300 nm in diameter. The first is the coat made up of protein that protects

the virus to a point. Next is the head that contains the genetic material for

the virus. The genetic material for a virus is DNA. The two other parts are

the tail sheath and the tail fibers that are used for odd jobs. I believe that a

virus is not considered to be a living creature due to the fact it is a

parasitic reproducer. To me it is just like ripping up a piece of paper because

it is still the same thing and it isn’t carrying out any other function besides

reproduction. Since the virus cannot continue to do its functions without

taking from a host and being a parasite it is considered an obligated parasite.

2. The adult fern plant in its dominate generation (sporophyte)

develops sporangium on one side of its leaf. When meiosis is finished inside

the sporangia and the spores are completed the annulus dries out releasing the

spores. The spore germinates and grows into a prothallus which is the

gametophyte generation. The antheridia and the archegonia are developed on the

bottom of the prothallus. The archegonia are at the notch of the prothallus and

the antheridia are located near the tip. Fertilization occurs when outside

moisture is present and the sperm from the antheridia swim to the eggs of the

archegonia. A zygote is formed on the prothallus and a new sporophyte grows.

4. Flowering plants have unique characteristics that help them survive.

One is the flower itself that contains the reproductive structures. The color

of the flower helps because it may attract birds and insects that spread the

plants pollen which diversify the later generation of plants. Flowers also

produce fruits that protect their seeds and disperses them with the help of

fruit eating animals.

5. Fungi, Animalia, and, Plantae are all believed to be evolved from

Protista. All 3 of these kingdoms are eukaryotic and their cells have a nucleus

and all the other organelles. Fungi live on organic material they digest,

Plants produce their own organic material, and Animals go out and find their

food. Animalia are heterotrophic whereas Plantae are photosynthetic. Fungi who

digest their own food on the outside are different from animals who digest their

food on the inside. Plants and animals both have organs systems but animals

have organized muscle fibers and plants do not.

8. The Gasreopoda , Pelecypoda, and the Cephalapoda all have three of

the same characteristics. The first one is the visceral mass that includes

internal organs like a highly specialized digestive tract, paired kidneys, and

reproductive organs. The mantle is the second one. It is a covering that

doesn’t completely cover the visceral mass. The last one is the foot that can

be used for movement, attachment, food capture, or a combination of these. The

Gastropods are the snails and slugs. They use their foot for crawling and their

mantle (shell) to protect their visceral mass. The class Pelecypoda consists of

clams, oysters, scallops, and mussels. These animals have two shells that are

hinged together by a strong muscle and these shells protect the visceral mass.

They use their foot for making threads so they can attach to things. Cephalopods

consist of octopuses, squids, and nautiluses. These guys use their mantle

cavity to squeeze water out and causes locomotion. The foot has evolved into

tentacles around the head that are used to catch prey. Nautiluses have an

external shells, squids have smaller but internal shell and octopuses lack

shells entirely.

9. The word Arthropod means jointed foot which come to some of the

features of an arthropod that are the jointed appendages, compound eyes, an

exoskeleton, and a brain with a ventral solid nerve cord. The class Crustacea

has compound eyes and five pairs of appendages two of which are sensory antenni.

Some examples are shrimp, cray, lobsters, and crabs. Insecta has 900,000

species in its class. For example in a grasshopper they have compound eyes with

five pair of appendages, three that are legs, one of which is for hopping, and

two pairs of wings. Spiders that belong to the class Arachnidia have six pair

of appendages. The first pair of appendage are modified fangs and the second

pair are used for chewing. The other four are walking legs ending in claws.

Spiders don’t have compound eyes, instead, they have simple eyes. More examples

are scorpions, ticks, mites, and chiggers. To similar classes are Diplopoda and

Chilopoda because they are segmented in the same way and each segment has a pair

of walking legs but in the Diplopoda some segments fuse together and seem to

have two pair of legs to one segment.

10.The Phylum Chordata contains creatures that would have bilateral symmetry,

well developed coelom, and segmentation. In order to be placed in this phylum

they must have had a dorsal hollow nerve cord, a dorsal supporting rod called a

notochord, and gill slits or pharyngeal pouches sometime in their life history.

In the subphylum Urochordata the only one of the three traits they carry on into

adulthood is the gill slits. In their tadpole form of their life they contained

all three of these characteristics. Subphylum Cephalochordata retain all three

qualifications into adult form and have segmented bodies. In subphylum

Vertebrata it has all three traits as usual but its notochord is replaced by a

vertebral column.

11. In these fish the sac-like lungs were placed at the end of the

fishes digestive tract. In their case when the oxygen level in the water they

were in was low they could still collect oxygen by breathing. After time these

sac-like lungs became swim bladders that control the up and down motion of a


12. The reptiles most helpful advancement in reproduction that helped

them live on land was the use of internal fertilization and the ability to lay

eggs that are protected by shells. The shells got rid of the swimming larva

stage and the eggs did everything inside of the shell. The eggs has

extraembryonic membranes that protect the embryo , get rid of wastes, and give

the embryo oxygen, food, and water. Inside the shell there is a membrane called

the amnion and is filled with fluid and is used as a pond where the embryo

develops and keeps the embryo from drying out.

13. The three subclasses of mammalia all have hair and mammary glands

that produce milk. Each of these classes also have well developed sense organs,

limbs for movement, and an enlarged brain. In the subclass Prototheria the

animals lay their eggs in a burrow and incubate. When the young hatch they

receive milk by licking it off the modified sweat glands that are seeping milk.

Subclass Metatheria the young begin developing inside the female but are born at

a very immature age. The newborn crawl into their mothers pouch and begin

nursing. While they are nursing they continue to develop. With the subclass

Eutheria the organisms contain a placenta that exchanges maternal blood with

fetal blood. The young develops inside the mothers uterus and exchanges

nutrients and wastes until it is read to be born.

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