Zoology Exam II

Fertilization: joining of sperm and egg cells

Cleavage: process of nucleus & cell divison in zygote

Parthenogensis: no sperm is involved, ONLY the egg multiplies/divides & becomes an organism

Morula: ball of cells, a solid mass e.g. baseball

Blastula: hollow ball of cells

Gastrula: hollow ball that begins to invaginate.

1. Spiral: first 2 planes are vertical = blastomere of equal sizes, 3rd plane is horizontal = blastomere are unequal e.g. mollusk, annelids



2. Radial: first 2 planes are horizontal = blastomere of equal sizes, 3rd plane is horizontal = blatomere are unequal e.g. starfish, frog

• 3. Rotational: one pair of blastomere comes to lie at right angles to others e.g. human
• 

4. Discodial: the cleavage is restricted to a small disc at one end of embryo e.g. birds



5. Superficial: Yolk is at the center & cleavage is in the outer surface e.g. anthropods

Protostomes develop a mouth first from the invagination and deuterostomes develop an anus first and the mouth after.

Isolecithal: equal amount of yolk to cleavage e.g. starfish & human

Mesolecithal: mocerate amount of yolk e.g. frog

Telolecithal: good/large amount of yolk e.g. birds

Centrolecithal: yolk in the center e.g. insects

Ectoderm: body surface, epithelial cells, nervous system

Endodermis: epithelial cells of G.I. tract

Mesodermis: muscles, reproductive, peritoneum

Diploblastic only have ectoderm and endodermis.

Triploblastic have all 3 germ layers.

Schizocoelous is when the coelom forms from cells that split off from the ectodermis.

Enterocoelous is when the coelom forms from cells that were pocketing out from the ectodermis.

Holoblastic animals have cleavage that completely divides whereas meroblastic animals' cleavages do not divide, only halfway because too much yolk

Sharp changes in embryonic development e.g. butterfly

Both are cells that are seperated from a blastula though a dissecting microscope. Regulative cells when cut and seperates function normally and the organism can still result e.g. sea urchin. Mosaic animals when the cells are sepearted, the animals that result will de defective e.g. mollusks.

Totipotent: one cell can become entire organism

1. There are two lambs, one with a black head and the other with a white head.

2. An egg cell is taken from the black head and the nucleus is removed.

3. A somatic cell from the white head is obtained and its nucelus is removed and put into the black head egg cell.

4. The cells are fused with a jolt of electricity and grown in petri dish.

5. The egg is implanted into the uterus of surrogate mother sheep.

6. "Dolly" the lamb is born with 95% genetic material as white headed lamb, 5% comes from black head because keeps the mother's mitochondria.

Multipotent: stem cells that can be driven to reproduce into many different cell types

Stem cells are taken from either embryo blastula cells or adult bones marrow cells. These cells are then cultured in petri dishes and can be grown into different organs e.g. liver, nerve cells

b

• Blastula -->
• Gastrula -->

• 1. Ectoderm:
• a. epidermis & associate strcutures e.g. hair, nails
• b. brain & nervous sytems

• 2. Endoderm:
• a. inner lining of GI tract
• b. glands e.g. liver & pancreas
• c. inner lining of respiratory tract

• 3. Mesoderm:
• a. notochord
• b. somites: - outer covering of internal organs
• - muscles
• - execretory system
• c. mesenchyme (loose migratory cells):
• - dermis (inner skin layer)
• - bones & cartilage
• - circulatory systems e.g. heart, blood vessel, etc.

3 --> 5 --> 10

• - Prosencephalon: 1. Telencephalon:
• a. basal ganglions
• b. olfactory
• c. cerebrum
• 2. Diencephalon:
• a. pineal gland
• b. thalamus
• c. hypothalamus

- Mesencephalon: Mesencephalon: mid-brain

• - Rhombencephalon: 1. Metencephalon:
• a. cerebellum
• b. pons
• 2. Myelencephalon
• a. medulla

Amnion: fluid filled sac that encloses the embryo & provides an aqueous environment in which the embryo floats, protection from shock/adhesions

Allantois: sac that grows from embryo's hindgut & serves as a repository for metabolic wastes during development, also is surface for exchange of O₂ and CO₂

Chorion: lies beneath eggshell & encloses the rest of the embryonic system

- Proposed binomial nomenclature based on comparative anatomy

- Taxonomy: the practice and science of classification

Dear King Phillip Cried Out For Good Soup

• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species

- First word is genus, written with capital initial letter

- Second word is specia, all small intial letter

- Both words are italic or underlined e.g. Homo sapiens or Homo sapiens

He was the first to propose the five-kingdom taxonomic classification into Animalia, Plantae, Fungi, Protista, and Monera. He also proposed the Whittaker Biome Classification, which categorized biome-types upon two abiotic factors: temperature and precipitation.

• Protista --> 1. Plants
• 2. Animals
• 3. Fungi

Anyone Can Make Pretty Hot Healthy Stew

• Kingdom: Animalia
• Phylum: Chordata
• Class: Mammalia
• Order: Primata
• Family: Hominidae
• Genus: Homo
• Species: Homo sapiens

• - No cell wall
• - In some ways motile
• - Ingest their food (heterotrophic)
• - Sexual reproduction

• - Have cholorplast for photosynthesis
• - Have vacuole for food, water & waste storage
• - Immobile
• - Autotrophic
• - Cellulose
• - Asexual repoduction

• - Unicellular
• - Microscopic
• - No germ layers
• - Specialized organelles
• - Free-living, mutualism (both parasite and host benefit), commensalism (one benefits, the other has no effect), & parasitism (one benefits & the other is harmed)
• - Some sessile, pseudopodia, flagella, cilia
• - All types of nutrition: autotrophic, heterotrophic
• - Aquatic or terrestial
• - Asexual or sexual repoduction

• - Mitochondria: produce ATP
• - Endoplasmic reticulum: manufacturing polypeptides/proteins, may contain ribosomes
• - Golgi apparatus: serves as packaging/collecting center for secreted polypeptides and proteins
• - Vesicles: small membrane-enclosed sack that can store or transport substances
• - Chloroplast: contain chlorophyll and is where photosynthesis takes places
• - Vacuoles: sac for food, water, waste storage
• - Ectoplasm: cortex of cell/part of cytoplasm just under the cell surface
• - Endoplasm: portion of cytoplasm that immediately surrounds the nucleus

- Cilia and flagella: 9+2 microtubules

- Pseudopodia: ectoplasm: transparent or hyaline colloid, endoplasm: more granular, more fluid

• By contractile vacuole
• - Small vesicles join the contractile vacuole
• - Then contractile vacuole joins the cell membrane e.g. amoeba

• In ciliates it is more complex
• - Excretory pore leads to outside & they are surrounded by ampulla in the endoplasmic recticulum
• - Ampulla fills up & discharges the water to the outside of the cell

- Autotrophs: makes their own food through photosynthesis

- Heterotrophs: have to take their food through other animals

- Phagocytes: cell eating

- Lysosomes: enzymes that cell releases to digest food

- Food vacuole: storage of food materials and wastes

- Exocytosis the waste material

- Cilia have cytoproduct for explusion of waste

- Pinocytosis: cell drinking through osmosis/difussion

- Fission: cell multiplication process when more individuals are produced

- Binary fission: two identical individuals are produced

- Budding: progeny is smaller than adult

• - Multiple fission:
• a. sporogony: development of spores/sporozites within oocyst
• b. schizogony: when cytokinesis is preceded by several nuclear divisions

- Isogametes: same size & identical DNA

- Anisogametes: not same size e.g. human egg and sperm

- Syngamy: fertilization of an individual gamete by another, same size but diff DNA

- Autogamy: gametic nuclei fuse to form zygote withing the same organism that produce them

- Conjugation: exchange or gametic nuclei between paired organism

- Encystment: formation of the cyst, protista cannot multiply, cyst forms to protect from unfavorable conditions, thick coat, low metabolism, almost hibernation-like, dormant until favorable conditions present itself

- Excystment: escape from cyst

- Parasites also do this to protect themselves from harm and then emerge once in environment that they need to survive

- Euglenozoa

- Dinoflagellata

- Chlorophyta

- Retortamonada

- Axostylata

- Apicomplexa

- Ciliophora

- Euglenozoa

• Euglena
• free-living
• asexual
• flagella

• Trypanosoma
• parasitic
• sexual
• flagella

• Leishmania
• parasitic
• sexual
• flagella & cilia

- Dinoflagellata

• Amoeba
• free-living
• asexual
• pseudopod

• Forminiferans
• free-living

• Radiolarians
• free-living

• Ceratium
• free-living
• sexual & asexual
• flagella

• Entamoeba coli
• commensalism
• pseudopod

• Entamoeba histolytica
• parasitic
• asexual
• pseudopod

• Entamoeba gingivalis
• commensalism
• pseudopod

• Naegleria fowleri
• free-living
• asexual
• flagella

-Chlorophyta

• Volvox
• free-living
• asexual & sexual
• flagella

• Chlamydomonas
• free-living
• asexual & sexual
• flagella

- Axostylata

• Trichomonas vaginalis
• commensalism
• (poorly understood)
• flagella

• Trichonympha
• mutualistic
• asexual & sexual
• flagella

• Dientamoeba
• parasitic
• asexual
• pseudopodia

-Apicomplexa

• Toxoplasma gondii
• parasitic
• asexual & sexual
• gliding

• Plasmodium
• parasitic
• pseudopod
• sexual & asexual

• Babesia
• parasitic
• sexual & asexual
• flagella & pseudopod

• Cryptosporidium
• parasitic
• asexual & sexual
• flagella & pseudopod

• Eimeria
• parasitic
• sexual & asexual
• gliding

• Isospora
• parasitic
• sexual & asexual
• flagella & pseudopod

- Ciliophora:

• Paramecium
• free-living
• sexual & asexual
• cilia

• Balantidium coli
• parasitic
• sexual & asexual
• cilia

- Retortamonada

• Giardia
• parasitic
• asexual & sexual
• flagella

• Euglenozoa
• Euglena
• Trypanosoma
• Leishmania

• Dinoflagellata
• Amoeba
• Entamoeba coli
• Entamoeba histolytica
• Entamoeba gingivalis
• Ceratium
• Radiolarians
• Foraminiferans

• Axostylata
• Dientamoeba
• Trichonympha
• Trichomonas vaginalis

• Apicomplexa
• Toxoplasma gondii
• Cryptosporidium
• Babesia
• Eimeria
• Isospora
• Plasmodium

• Chlorophyta
• Volvox
• Chlamydomonas

• Ciliophora
• Paramecium
• Balantidium coli
• Retortamonada
• Giardia

- Reproduction by binary fission

• Structures
• - Pellicle: outside the bactier
• - Kinetosome: DNA material at the base of flagella
• - Contractile vacuole
• - Stigma to locate light
• - Cholorplast
• - Paramylon bodies: store starches

• - Multicellular organism
• - Sexual/asexual reproduction
• - Photosynthetic

- Believed by biologists to have been the precursor to more complex organisms e.g. animals/humans

- Trypanosoma brucei rhodensiense: causes brain damage, VERY harmful in humans and kills sometimes

- Trypanosoma brucei gambiense: also found in humans but less harmful than rhodensiense

- Trypanosoma brucei brucei: found in animals

- All 3 are transmitted by tse tse fly (Glossina), called the African Sleeping Sickness disease

- Trypanosoma cruzi: found in south/central America, causes Chagas' disease and heart problems, transmitted by kissing bug Triatomnae

• - Leishmania is transmitted by the sand fly
• - Visceral Leishmania affects the liver/spleen

- Cutaneous Meishmaniasis affects the skin

- Cause Giardiasis, which in humans is a diarrheal infection of the small intestine by a single-celled organism

- Method of infection: man ingests infective cysts, transmitted by faces, fingers, food, formites or flies

- Cyst passes to small intestine, excystation occurs

- Giardia lamblia (flagellate) trophozoites in large intestine, multiply asexually by binary fission

- Diagnostic & Infective stage: resistant, infective cysts passed in feces (trophozoites may be found more commonly in soft/fluid feces)

- parasite found in the gastrointestinal tract of some humans, pigs and gorillas

- Causes gastrointestinal upset in some while in others it does not

- Belongs to phylum axostylata

- Causes vaginitis which is the inflammation of the vagina

- Causes fish-like odor, pain/itchiness of vagina, stinging and is sexually transmitted

• - Entamoeba histolytica
• both cause severed diarrhea
• sometimes called amoebia dysentery because of stool with blood in it

• - Entamoeba gingivalis
• found in the mouth
• has a mutualistic symboisis relationship with its host
• if maintenance of the mouth is not kept up gingivitis occurs

• - Naegleria fowleri
• gets into the brain
• causes death within 5-7 days, found in autopsy
• cause disease called amoebia meningoencephalitis (the brain)
• flagella & amoeboid trophozites
• binary fission
• intraveneous amphotericin (antibiotic)

• GET IT IN
• - ponds/lakes
• - water into nose
• - immersion in bath
• - play in warm puddle after rain
• - put head in trough of water in school
• - baptism through immersion

- All parasitic

- Causes death in humans

• - Apical complex
• Rhoptries
• Microenemes

- Pseudopodia in some intracellular stages

- Flagella in gametes of some species

- Asexual/sexual cycles

- Some require intermediate hosts as opposed to definitive/primary hosts

- Some develop oocyst/spores

• - Babesia causes diarrhea/upset stomach and is a malaria-like parasite
• - Babesia bigemina causes red-water fever in cattle, first found in Texas, known as Texas Cattle Fever

- Cryptosporidium causes severe diarrhea, found in contaminated drinking water

• - Eimeria & Isospora cause coccidiosis
• - Eimeria causes bloody diarrhea
• - Isospora is fatal in AIDS patients

- Oocyst: a cyst containing a zygote formed by a parasitic protozoan such as the malaria parasite

- Cyst: a closed sac, having a distinct membrane and division on the nearby tissue; may contain air, fluids, or semi-solid material

• Plasmodium
• - Sporozoites develop in oocyst and are released, migrating to salivary glands
• - Mosquito infects human by injecting saliva
• - Injected sporozoites migrate to liver
• - Sporozoites migrate to liver
• - Enter liver cells, undergo schizogony
• Asexual cycle
• - Merozoites released from liver cells
• - Merozoites enters red blood cells and undergo schizogony
• - Female mosquito bites human & ingests gametocytes

• Eimeria
• - Eimeria tenella in young fowl (chickens transmit to humans)
• - Reproduction of Eimeria
• Schizogony --> gametes --> fertilization --> oocysts in intestines/in feces
• Sporogony --> in oocyst --> 8 sporozoites --> outside of host, new host ingests

• - Causes Toxoplasmosis
• - Very harmful in AIDS patients
• - Primary host are cats
• - Other mammals are possible intermediate hosts

LIFE CYCLE IN CATS

• 1. Cat eats oocyst/cyst
• 2. Cyst release bradyzoites in stomach/intestines/oocyst releases sporozoites that differ into tachyzoites & invade tissue
• 3. Bradyzoites invade epithelial tissue & start division
• 4. Bradyzoites differentiate between tachyzoites (asexual) & gametocytes
• 5. Gametoxytes fuse 2 form zygote that matures into oocyst
• 6. Oocyst released w/ feces

• LIFE CYCLE IN OTHER MAMMALS
• 1. Mammal eats oocyst/cyst
• 2. Cyst release bradyzoites in stomach/intestines/oocyst releases sporozoites that differ into tachyzoites & invade tissue
• 3. Bradyzoites invade epithelial tissue & start division
• 4. Bradyzoites differentiate into tachyzoites
• 5. Tachyzoites invade almost any type of cell, mutliplying until cell dies and releases more tachyzoites
• 6. Tachyzoites differentiate into bradyzoites and form cysts mainly in brain, liver and muscle tissues

- During the first few weeks of exposure, the infection causes a mild flu-like illness or no illness

- After, the parasite rarely causes any symptoms in healthy adults

However, those with a weakened immune system, such as AIDS patients or pregnant women, may become seriously ill, and it can occasionally be fatal

- Parasite can cause encephalitis (inflammation of the brain) and neurologic diseases

- Can affect the heart, liver, inner ears, and eyes, also brain cancer

- Mostyle free-living, some parasitic, some commensalistic, and some colonial

- Some sessile, suctorians

- Larger than most protozoan

- Multinucleated

- Undualting membrane: cilia are fused into a sheet

- Cytosomes (mouth)

- Oral groove

- Two contractile vacuole system

- Passage of water/food in paramecium

- Oral groove --> cytosome --> cytopharynx --> food vacuole --> indigestible out by cytoproduct

• - Balantidium coli is transmitted through contaiminated water that has pig/human feces
• - For some people, causes fatal disease of the gastrointestinal tract
• - Can cause explosive diarrhea every 20 minutes

- Paramecium is free-living

1. Macro/micro nuclei are present

2. Micronuclei undergo meiosis I & 4 pairs of micro nuclei result

3. Micronuclei undergo meiosis II & all 3 pairs of mircronuclei disintegrates

4. Macronuclei also shrinks in size and undergo mitosis

5. One pair of micronuclei & one pair of macronuclei (small size now) result

6. Two nuclei travel and fertilize the other, results in zygotes

7. Macronuclei forms again in autogamy stage

8. Binary fission occurs and cytokinesis w/ 2 cells each with macro/micro nuclei in each