Module 2: Eukaryotes

Plasmodermata

- A channel that allows cytosol to pass between plant cells - unique to plant cells -has a similar function to the cell junctions found in eukaryotic cells

Fungi have various Industrial Uses:

- Bakery -Beer Brewing - food yeast - feed yeast - wine making - industrial alcohol/ spirits - yeast products (autolysates, biochemicals)

Eucoelomates are subdivided into 4 smaller cavities- what are they

- Dorsal cavity (brain & spinal cord) -thoracic cavity (heart & lungs) -abdominal cavity (most digestive organs) -pelvic cavity (reproductive organs & urinary bladder)

Metabolic byproducts of fungi are important medically & industrially

- EX) Yeast (saccharomyces cerevisiae) is used by bakers & brewers - the CO2 given off during anaerobic fermentation of the yeast is used to make bread rise, & the ethanol (alcohol) byproduct is used to make wine/beer - fungi may also produce enzymes that can be used as antibiotics or biological pesticides

Protists have mechanisms to maintain homeostasis: a major homeostatic challenge for protists is maintaining osmolarity, or osmotic concentrations.

- Single celled protists gain & lose solutes by simple diffusion & water through osmosis - as single celled organisms, minor environmental changes to an aqueous habitat can quickly result in death - regulation is maintained by a special structure called the contractile

Dueterostome

- a radical clevage occurs in the cell mass which results in cells of an upper & lower tier being radially oriented around a central axis (an example is the sunflower - the pistil (middle part) is surrounded by the petals. This example is a visualization of radical clevage) - this clevage causes the blastopore to develop in a different orientation *** the blastopore will develop into the anal opening of the organism***

Fungi are characterized as having

- a rigid cell wall composed of chitin

radial symmetry

- an organism's body can be visualized as equal halves when a plane is passed from top to bottom & through the center - arrangement of body parts around a central axis, like rays on a sun or pieces of a pie EX) sponges, jellyfish, starfish exhibit radial symmetry

Fungi have an ecological role similar to bacteria:

- b/c they are close to the ground or in the ground they occupy the niche of "decomposer" - detritus/ organic material falls to ground is acted upon by fungi (&bacteria) & contribute to byproducts that may be further decomposed by earthworms or directly contribute to nutrients in the soil for plants to keep growing

Although some plants are pretty to look at, there are some plants that are harmful; there is a variety of human & plant interactions that occur

- brushing up against Poison Ivy - stinging nettle release chemicals in skin - mistletoe leads to blurred vision -foxglove contains digitalis which in large amounts can be fatal

Fungi

- can be unicellular/ multicellular (mainly unicellular) - includes: yeasts, molds, rusts, mildew, & mushrooms - some are microscopic

Prokaryote Kingdom: Monera

- controversial kingdom - not all scientist recognize it as a kingdom & choose to split organisms w/in this kingdom between umbrella of bacteria & archaea

Animalia kingdom is diverse and includes the smallest ant to complex human beings

- estimated to be ~ 9-10 million different species w/in this kingdom - classification of animalia species can be very challenging

Eucoelomates

- have a true coelom that surrounds a gut (primative/complex digestive system) - humans are broadly classified as Eucoelomates & are anatomically subdivided into (4) smaller cavaties

Vascular Plants

- have cells joined into tube-like structures that allow for the transport of water & nutrients throughout the body -have tissues made of cells that transport water and nutrients throughout the plant - EX) angiosperms (flowering plants, conifers, & ferns

Acoelomates

- have no true body cavity, but still meet other classification requirements to be considered an animal - EX) flatworm

Infections of crops can cause economic instability & mass starvation

- historical examples of plant infection outbreaks include the Blight of the Potato Plant in Ireland which led to the Great Irish Famine of 1845-1849 - The Panama Disease (banana wilt) outbreak of the 1950s ** Both were the result of different species of pathogenic fungi *** Blight is a general term that refers to the destruction of the plant leaves & roots which results in wilting & severe browning or yellowing

Plasmodium are obligate parasites of vertebrates w/ a complex life cycle

- humans become infected after a female anophele mosquito carrying the parasite bites a human. - the parasite will enter the bloodstream, carry out a portion of its life cycle within the host's liver, & eventually enter the bloodstream again to infect & lyse RBCs - there are 4 species of Plasmodium that are responsible for causing malaria infections in humans: 1. P. falciporum 2. P. ovale 3. P. malariae 4. P. vivax

nonvascular plants (AKA bryophytes)

- lack the formation of tubes to transport water & nutrients - Plants that lack a well-developed system of tubes for transporting water and other materials - EX) mosses, liverwarts, & some types of green algae

Chloraplast

- most notable plastid; contains pigment chlorophyll which mediates the process of photosynthesis -a plastid that contains chlorophyll and in which photosynthesis takes place. - is only (1) of several types of plastids w/in a plant cell

Protista Kingdom

- mostly unicellular, but small amount are multicellular - most are heterotrophic & engulf matter (phagocytosis) but there are a few autotrophic species that rely on photosynthesis-like processes to harvest energy - exhibit wide range of inter-kingdom variability

Eukaryotic Kingdom: Plantae

- organisms of this kingdom are multicellular - autotrophs (able to form nutritional organic substances such as CO2 from the sun) - in addition to the presence/absence of vascular tissue, plants may also be classified by the presence/absence of seeds

Organisms w/in Plantae vary in their reproductive life cycles

- plants may reproduce asexually through various processes (budding, fragmentation, spore formation, vegetative propagation or fission) - flowering plants reproduce sexually by which male & female gametes fuse to produce new offspring

Plastids

- small organelle used for producing/storing food -A group of membrane‐bound organelles commonly found in photosynthetic organisms and mainly responsible for the synthesis and storage of food.

plasmodium reproduces sexually & has 6 different stages in their life cycle

- the complexity of life stages is advantageous for Plasmodium, making it difficult for the immune system to respond effectively - developing interventions, like treatments, is also challenging b/c of the complex life cycles

Organisms in the Protist kingdom exhibit diversity in their reproduction & life cycle

- the majority undergo binary fission which is a type of asexual reproduction. - Some protist sexually reproduce - gametes are formed & the fusion of the 2 results in genetically distinct offspring

Protists can play a role in a variety of diseases

- the most widely known protozoan infection in humans are those caused by Plasmodium & results in Malaria

Fertilization & development are remarkably similar across the species in this kingdom

- this is interesting when making comparisons of animals that are hatched from an egg and those that undergo extensive gestation & live birth

Chitin

-A chemical that provides both toughness and flexibility -fibrous substances consisting of polysaccharides forming the major constituent in the cell walls of fungi

Clevage

-Cell's cytoplasm start to divide. -rapid mitotic division right after fertilization

Certain types of the fungal species can interact w/ humans, causing infections:

-Fungal Infections -Mold Fungal infections -Yeast Fungal infections - Tinea Unguium - Histoplasmosis (AKA: Ohio Valley Fever) *most common fungal infection in the US *spores *risk factor= exposure to bird/bat droppings

Domain: Eukarya :Kingdom: Animalia

-Largest kingdom - 36 Phylum - over 10 million species

These microscopic organisms are some of the oldest inhabitants of the plant

-have endured the test of time -have developed mechanisms & niches allowing them to colonize w/in all the different eukaryotic kingdoms -EX) Pectobacterium (prokaryote) can pathogenically colonize the plantae kingdom but is non-pathogenic to animalia and fungi kingdoms -EX) Streptococcus Pneumoniae will induce illness in humans but not in plants -EX) Clostridium tetani (tetanus) is a soil bacterium & is non-pathogenic to plants, but can cause fatal illness if introduced subcutaneously in human tissues

Haustoria

-allows fungi to extract nutrients from plants -specialized parasitic hyphae that invade living cells and secrete digestive enzymes

Diversity in physical traits of animalia has led to classification based on anatomical characteristics:

-animals are often grouped by BODY PLANS

Pseudocoelomates

-animals that do not have a true body cavity -while they may appear to have a fluid-filled region, upon microscopic evaluation, the cells lining the space are not continuous & do not completely surround the space EX) roundworm

Animalia are distinguished by:

-body plans - genetics - anatomy - physiology

bilateral symmetry

-can be visualized as one plane dividing an organism body into (2) equal halves -can be thought of as Left & Right lateral sides EX) most invertebrates (worms, clams, snails) and all vertebrates

Coeloms

-fluid filled body cavities, leaves room for our body organs and allow them to be cushioned by our fluid-filled bodies - the presence/absence of coeloms is a classification heuristic - Body cavities may suspend organs, give shape, & enclose delicate organs

Eukaryote Characteristics (7):

-larger cells -organisms are single or multi cellular - contain true nucleus -contain membrane bound organelles -cell walls are present in some cell types - Mitosis & Cell Cycles -Diversity of movement mechanisms

Plants are important to humans as a crop food source, accounting for 80% of the calories ingested by humans

-maize, rice, & wheat are staples of our modern day diets - flowering plants provide luxuries such as chocolate (cacao tree), coffee beans, fruits, seeds, & seed extracts that humans consume - Food crops aside, many cultures have historically used plants as a source of herbal remedies

Plant cells have many of the same organelles as eukaryotic cells, however, there are some organelles plants have that eukaryotic cells do not:

-presence of a cell wall -chloroplasts -central vacuole -plasmodermata

Protostome

-spiral clevage occurs in the cell mass -results in cells as an upper tier, spiraling over a lower tier -both tiers are wrapped around a central axis (like a candy cane- red & white spiral stripes is a great visualization of a spiral clevage) - the clevage results in a blastopore = the opening of a structure that will begin to differentiate into different cell types which will then become the most rudimentary body cavities (coelom) as development continues **** the blastopore will develop into the mouth of the organism****

There are many specialized cell types, esp. in mammals & humans:

-stem cells -chrondrocyte -egg cell -intestinal cells -neuron -smooth muscle cells -sperm cell -erythroid cell -fat cell -monocyte -lymphocyte

Spherical symmetry

-the body of an organism can be visualized as similar halves of any plane that passes through the center -a body pattern that can be divided into equal halves by a cut in any direction as long as it passes through the center point of the body EX) sponges & some coral have spherical symmetry. Animals with this type of symmetry as spherical in shape

Generally there are 3 types of body cavity classifications in animals:

1) acoelomates 2) Eucaelomates 3) pseudocoelomates

Body Plans have symmetry which may be:

1) spherical 2) radial 3) bilateral

Plasmodium life cycle

1. Mosquito ingests the parasite by feeding on blood from an infected human carrier 2. Parasites reproduce sexually in the midgut of the mosquito and migrate to the salivary glands 3. Parasite is transmitted when infected mosquito takes a blood meal 4. Within 3 minutes, parasites reach and infect liver cells, and for 5-16 days multiply inside (no symptoms) 5. Parasites re-enter blood stream infect red blood cells and multiply 6. Infect blood cells burst, releasing new parasites, which infect more blood cells. Some develop into gametocytes 7. Periodicity of cycles corresponds with typical chill/fever symptoms and with Plasmodium specie

Fungi Anatomy

1. Mycelia( underground network of branched Hypae for nutrition absorption (Roots). Cell wall made of chitin. 2. "mushroom" fast growing, spore producing reproductive structure (located under hood) Septum, cell wall, pore wall, nuclei

Instead of 7 key features, focus is often placed on only 5:

1. Organism 2. Regulation 3. Energy & Metabolism 4. Interactions & Adaptations 5. Reproduction

Fungi have 2 types of reproduction

1. asexual- creation of offspring identical to parent 2. sexual- offspring similar to parent but not identical

Animalia is a kingdom of consumers, and therefore must ingest other living organisms or non-living organic matter

A consumer is a an organism that obtains energy by feeding on other organisms

Rapid cell division begins & after 8 rounds of division, a cleavage begins to form in the cell mass

At the cleavage stage, animals can be classified into 1 of 2 strategies: Protostome or Dueterstome

It is important to note that not all animals have organs or organ systems - the simplest members of this kingdom may only be composed of a few cell types & tissues

As cell diversity increases (including diversity in tissues, organs, & systems) so does the likelihood of diversification in the overall physical traits of the organism

Protists can move in a variety of ways using cell surface structures:

Cilia, flagella, or pseudopodia (temporary protrusion of the surface for movement & feeding)

While the cells are eukaryotic, they are increasingly complex & contain a diversity of structural proteins

Collagen

Plant phylogeny is complex & extensive, with taxa being grouped by reproduction cycles, types of roots & leaves, & flowering characteristics

Common to all is the key characteristic of containing plastids

Humans & other animals w/a spinal cord are classified as

Dueterostomes

While many areas of the animal kingdom exhibit an enormous amount of diversity, one area of classification that does not is reproduction

Most reproduction takes place sexually followed by the formation of a zygote that undergoes further developmental changes to become an embryo

Some fungi reproduce asexually by:

Fragmentation, budding, or forming spores

Some species of Monera may be pathogenic to more than (1) kingdom

EX) Pseudomonas aeruginose (Gram (-)) can cause wilting & rot of lettuce plants & is capable of establishing colonization of the blood, lungs, skin, & urinary tract of humans ***For people with healthy immune systems the risk of plant P. aeruginosa establishing an infection is rate, in people with compromised immune systems it is more common - plant to human P. aeruginosa infection is a remarkable opportunistic mechanism of some Monera species

Hemostatic mechanisms are also very diverse & dependent on what kind of plant is in question

EX) deciduous trees (shedding leaves annually) losing their leaves to reduce energy metabolism requirements in the winter months when sunlight is shorter during the day

In Animalia, cell types are differentiated into tissues which serve as coordinated units to carry out functional, structural, & metabolic tasks

EX) how tissues form organs, organs w/ similar functions form organ systems

Less common w/in the animalia kingdom is asexual reproduction

EX) pathernogenesis (reproduction from an ovum w/o fertilization, esp as a normal process in some invertebrates & lower plants) -budding & fragmentation but goes beyond the scope of this course

The protist life cycle is diverse & varies by species w/in the kingdom

EX) plasmodial slime begins life as a spore & then undergoes a series of growth phases. Once adulthood is reached, the single cell molds (plural) will congregate to form a united, multinucleated mass that functions as a coalesced unit EX) amoeba type protists have a life cycle that involves binary fission followed by a minor growth cycle. One adulthood is reached, the single celled amoeba forms aggregated masses, but continue to carry out life processes as individual (autonomous) adult organisms

The majority of Protist tend to be single celled, aquatic organisms

EX) plasmodium = are obligate (can't survive unless in a host) parasites (Malaria) - sexual reproduction & requires both mosquito & human hosts - human cell affected: liver & RBCs (which are lysed) - Malaria begins with a mosquito biting a human. When mosquito lands on skin and bites, it injects plasmodium into circulation where it occupies the liver & RBCs

Although mostly simple & unicellular, Protists can respond to their environments through biochemical & light stimuli

EX) protists are attracted to light through positive photropism (upward) & they avoid harmful stimuli (predators, harsh temps, or poor oxygenation) through negative tropism (move away)

Much like plants, animals are multicellular organisms but not in the sense of a lot of different cells but each specific cell type organizes itself into tissues

EX) smooth muscle cell has distinctions (spindle shaped) but aren't by themselves but are held together in a tissue layer & for the most part are flat. These cells make up one of the many layers of the stomach yet the inner layer of the stomach is made of epithelial cells yet another layer is made of connective tissue cells. So different types of tissues can make up an organ which ends up being an organ system

In the ecosystem, fungi help maintain homeostasis by decomposing plants & animals

Fungi are also at the bottom of the food chain and are known as decomposers

Eukaryote (eukarya) Domain consists of four Kingdoms:

Fungi, Protists, Plantae, & Animalia

Hyphae can can modified into structures called:

Haustoria

Digitalis is cultivated in many different places; In Europe it was used in the 1700s as an herbal remedy; Dr. Withering discovered, by accident, foxglove when asking for help from herbalists. He noticed that the concoctions he would give his patients caused their heart problems to get better. He sifted through the ingredients in those concoctions and found that it was the foxglove plant that was helping his patients.

He was able to figure out proper dosing (small/low amounts worked best while large/high doses could be fatal). Foxglove is a lipid compound which is a precursor from cholesterol to make digitalis

** passing a plane in other directions allows for scientist to classify animals based on anatomical body types

Imagine looking at a common house cat & passing an imaginary planes through it. Passing a line through the center of the cat results in his head being in the anterior (front) position and the tail being in the posterior (back) position - we would pet a cat on the dorsal (top) surface and his underside is the ventral (bottom) surface

Body Plan

In animals, a set of morphological and developmental traits that are integrated into a functional living organism.

Animalia also has diversity in the types of cells. Humans for example have approximately 200 different kinds of cells

In contrast, sponges (Phylum Porafera) are considered to be some of the simplest members of the animal kingdom & may have as few as (3) types of cells composing their bodies

Protist's metabolic processes are diverse & may be both aerobic & anaerobic

Majority are obligate aerobes, & oxygen is required for metabolic biochemical reactions; there is a small subset of protists that use anaerobic pathways

In contrast to protists, plants do not have the ability to move away from environmental stimuli

Many of the observed adaptations are the result of the environmental conditions EX) desert plants have a thick, waxy coating to prevent water loss while forest plants often have very large leaves that can "withstand excessive heavy rains"

Eukaryotes also have a plasma membrane that encloses cellular organelles & the nucleus

Membranes of eukaryotes are composed of unbranched fatty acid chains attached to a glycerol via ester linkages

Plasmodium Life Cycle (Malaria)

Plasmodium life cycle and malaria: 1. When a mosquito (anopheles) carrying the infective stage of plasmodium, called a sporozoite, bites a human, sporozoites can be injected into the human. The sporozites are carried by the blood to the liver 2.) They undergo schizogony in liver cells and produce thousands of progeny called merozoites 3.) Merozoites enter the bloodstream and infect RBC 4.) Merozoite develops into ring stage in RBC 5.) The ring stage enlarges and divides repeatedly 6.) The RBC eventually ruptures and release more merozoites. Merozoites infect new RBC or some develop into male and female sexual forms (gametocytes) 7.) They can be picked up by the bite of another mosquito; they then enter the mosquito's intestine and begin their sexual cycle. 6.) Here the male and female gametocytes unite to form a zygote. The zygote forms an oocyst, in which cell division occurs and asexual sporozoites are formed. 9.) When the oocyst ruptures, the sporozoites migrate to the salivary glands of the mosquito. They can then be injected into a new human host by the biting mosquito.

Leucoplast

Plastid, generally colorless, that synthesizes and stores starch and oils.

The hyphae are segmented into septa

Septa are large pores that allow for the flow of cellular organelles (Ribosomes, nuclei, & mitochondria) from cell to cell

Fungi may be pathogenic or non-pathogenic to humans

Some pathogenic species can cause parasitic infections known as mycotic infections in both humans & animals

contratile vacuole

The cell structure that collects extra water from the cytoplasm and then expels it from the cell - while this is an interesting physical feature, most protists are relatively simple & don't have additional complex biochemical pathways to deal with precarious solute changes

Mycotic infections (infection caused by fungi) may be superficial (Tinea pedis (Athletes Foot)0 or Tinea Corporis (Ring Worm))

These types of infections are usually uncomplicated & easy to treat w/ antifungal medications

In 1930s, Dr. Alexander Fleming from Scotland had a habit of culturing his bacteria which allowed growth of staph. After returning from vacation he looked at some of these growths and notice near the colony there was a large area of mold also growing. Around this colony he saw an area where there was a "clearing of growth" in which the growth of the bacteria was inhibited. The mold that was growing on the same dish as the staph was a Penicillin colony

This discovery led to Dr. Fleming getting a Noble Prize for the discovery of Penicillin - after several years, it was noticed that signs where pointing to a resistance of Penicillin by the bacteria= it found a way to produce beta lactamase which is an enzyme that is resistant to Penicillin

While Plantae cannot cause infections, it can produce allergic reactions in humans, and ingestion of toxic plants can be lethal

This kingdom is unique b/c none of its members can produce pathogenic infections - saps, poison ivy can produce an itchy, painful, rash - pollens can cause sneezing, watering eyes, and runny noses for seasonal allergy sufferers

As living organisms, fungi must also have mechanisms to regulate the biochemical processes of life

Unlike plants, fungi do not manufacture their own food despite many varieties being wrongly associated with photosynthesis

Amyloplast

Unpigmented plasids that store starch grains, abundent in cells of stems, tubers, and seeds

all animals that reproduce sexually can be classified by their early developmental characteristics discussed above

at the end you get an embryo that looks the same but how they got there is different

Candidiasis

can be superficial but disseminated (spread throughout) disease may occur if a species (candida albicans) gains access to the bloodstream & adhere to internal body organs & tissues= the fungi produce tissue damaging toxins

For our purposes, this taxon is included as a means to collect all prokaryotic organisms under a single kingdom: monera

can be thought of as less complex in terms of characteristics of life

Fungi are heterotrophs

cannot manufacture their own food & must take in organic molecules to use as energy source

As defining characteristic, eukaryotes cells contain a membrane bound, true nucleus where

genetic material is located

Histoplasmosis

is caused by breathing in histoplasma spores which are often found in bird/bat droppings & results in Acute Respiratory Distress Syndrome (ARDS)= damages delicate lung tissue & prevents proper oxygenation of blood

Ester Linkages

linking (2) hydrocarbon groups together w/ an oxygen atom OR by linking a phosphate/nitrogen to a hydrocarbon group w/ an oxygen atom

Deep mycotic infections

may be subcutaneous or systemic - such infections are serious threats to those w/ compromised immune systems (HIV, Chemo tx) - EX) Histoplasmosis & Candidiasis

blastopore

the opening of the central cavity of an embryo in the early stage of development.

Eukaryotic cells use processes of oxidative metabolism on

the surface of mitochondria for energy

binary fission

type of asexual reproduction in which a parent body (organism) replicates its DNA and seemingly pinches off into 2 halves resulting in two identical daughter cells each with its own nuclei

chromoplasts

type of plastid that stores pigments that are responsible for the bright colors in fruit and flowers

After fertilization, the united gametes are called blastocysts

which are a hollow mass of cells

After fertilization of fungi, they grow as thin, threadlike structures called Hyphae

which consist of tubular walls which surround the plasma membrane & cytoplasm of individual fungal cells