bio exam 1

_____ are mainly used for ______ storage (glycogen), but can be used for _________ support (cellulose) in plants

Carbs, energy, structural

_______ are diverse _________; ________ and ________ serve as an important energy source and source of essential ________; make up _________ in biological membranes; and make up ________ used for cell communication

Lipids, hydrophobic macromolecules; fats, oils, fatty acids; phospholipids bilayer; steroids

________ have a wide range of function and chemical properties; they aid in maintaining _______ and ________ (keratin), help in _______ (amino acids for growth), they also aid in contractile ________, _________, and _________ (enzymes)

proteins; shape and structure, storage, movement, transport, and chemical reactions

Nucleic acid

carries genetic info of the cell (DNA) and instructions on making specific proteins (RNA)

Cell membrane

separates the interior of the cell from the external environment, and controls what comes in and goes out of the cell

Nucleus

where DNA is stored (membrane bound organelle)

Endoplasmic reticulum

where proteins are made (membrane bound organelle)

Golgi apparatus

stores info on where to send newly made proteins and lipids (membrane bound organelle)

Mitochondria

creates all the energy the cell needs (membrane bound organelle)

Vesicles

shuttles proteins between different parts of the cell (membrane bound organelle)

Taxonomic ranks

Domain, kingdom, phylum, class, order, family, genus (italics), species (italics and lowercase) (everything besides species is uppercase/capitalized)

The three domains of life

Bacteria (unicellular), Archaea (unicellular), and Eukarya (multi or unicellular)

How can one classify an organism as belonging to one of the three domains of life?

The presence or absence of membrane bound organelles (mbos only in eukarya), number of cells (multi/ unicellular), and metabolism

List the kingdoms of life

Eubacteria (Bacteria), Archaebacteria (Archaea), Protista (Eukarya), Plantae (Eukarya), Fungi (Eukarya), and Animalia (Eukarya)

A phylogenetic tree

depicts the relationship between different species or groups of organisms

What do the tips of phylogenetic trees represent?

Species or group of species

What do the nodes on phylogenetic trees represent?

A common ancestor

What is a branching event?

A point where a new group of species formed (different common ancestor)

Prokaryotes are _______ microorganisms, they don’t have a _______ or other ___________ organelles , they do have cell ______

single celled, nucleus, membrane bound, cell wall

Transcription and translation in Archaea is

more similar to Eukaryotes

Peptidoglycan comprises the

Bacterial cell wall

Archaean cell walls can be made of

pseudopeptidoglycan or other components

The Archaean cell membrane can be a

lipid monolayer

DNA is packaged similarly in Archaea and

Eukarya

Prokaryotes are vastly ______ with _______ of different species

diverse, millions

Prokaryotes can (environment)

live in environments similar to ours and extreme environments

What is a microbial mat and what do we know about its history?

A microbial mat is a multi-layered sheet of prokaryotes that could have been the earliest form of life on Earth

The earliest records of life are

fossilized microbial mats called stromatolites

What are some effects of cyanobacteria releasing oxygen?

An increase in atmospheric oxygen, which led to the creation of the ozone layer, and the rise of complex organisms. As well as the development of better oxygen utilizing catabolic pathways

What is an extremophile?

Bacteria or archaea adapted to growing and surviving in extreme conditions

What is an example of an extremophile?

Acidophiles that thrive in a pH of 3 or below

How are prokaryotes cultured in the lab?

Through a liquid broth or solid agar culture medium that contains all nutrients needed for the prokaryote’s survival

Why is it difficult to culture prokaryotes in a lab?

There’s a lack of knowledge in terms of feeding and growing them, and it’s hard to replicate the organism’s natural habitat within a lab environment

Define biofilm

A microbial community held together by an extracellular matrix that consists primarily of complex carbs and proteins secreted by microbes

Biofilm initial attachment phase

Bacteria moves to new environment, it has a weak attachment to the surface and is easy to kill off

Biofilm irreversible attachment phase

Has a more permanent attachment, the pili anchor bacteria to the surface

Biofilm maturation 1 phase

The bacteria multiples and starts to excrete the extracellular matrix made of complex carbs and a few proteins

Biofilm maturation 2 phase

Recruitment of different types of bacteria, the bacteria continues to divide and takes different shape/structure

Biofilm colonization/dispersal phase

The bacteria leaves the biofilm and goes to a new environment to create a new biofilm

Prokaryotic classification

cocci (sphere), bacilli (rod), spirilla (spiral)

Gram-negative bacteria have

A thin peptidoglycan cell wall and an outer cell membrane (in addition to the plasma membrane) (does not trap crystal violet stain, needs counter stain)

Gram-positive bacteria have

A thick peptidoglycan cell wall and no outer cell membrane (it does have a plasma membrane) (does trap crystal violet stain)

If Archaea have a pseudopeptidoglycan cell wall it can stain

gram-positive

Prokaryotes reproduce through

asexual binary fission

In binary fission within prokaryotes

the cell replicates DNA, elongates and divides into two identical daughter cells

Transformation increases genetic diversity in prokaryotes by

absorbing prokaryotic DNA directly from the environment

Conjugation increases genetic diversity in prokaryotes by

the transfer of DNA from one cell to another through a mating bridge

Bacteria is vital to human life because it

moves carbon through the environment, makes nitrogen available to plants by transforming it to ammonia or nitrates, can be used as bioreactors to make important drugs, and live within the human microbiome which keeps us healthy

What is antibiotic resistance?

The excessive use of antibiotics, leading to the natural selection of resistant forms of bacteria

How does antibiotic resistance emerge?

Bacteria causing illness exists with some being drug resistant, the antibiotic is administered and the bacteria causing the illness is killed along with good bacteria. The only bacteria remaining is the drug resistant bacteria which is allowed to flourish. This bacteria can give their resistance to other bacteria, making them antibiotic resistant as well

All Prokaryotic cells have hair-like projections called pili

False

Prokaryotes were the first living organisms to evolve

True

The main difference between gram-positive and gram-negative bacteria lies on the structure of the plasma membrane (cell membrane)

False

Some prokaryotes consist of more than one cell

False

Prokaryotic cells are much smaller than eukaryotic cells

True

Oxygen is toxic to all known prokaryotes

False

Eukaryotes possess

cells with nuclei (surrounded by a nuclear envelope), presence of mitochondria, and chromosomes organized by histones

Eukaryotes reproduce

sexually, although some have lost the ability to produce sexually, and some can reproduce both sexually and asexually

Cell division in eukaryotes occurs via

mitosis

For cell movement eukaryotes use

flagella and cilia

What is endosymbiosis?

specific type of symbiosis, where one cell engulfs another cell, such that the swallowed cell survives and both cells benefit

Mitochondrial shape is similar to many ________ which supports the _________

Alpha-Proteobacteria, endosymbiotic theory

Mitochondrial inner membrane is similar to the _________ which supports the ________

bacterial plasma membrane, endosymbiotic theory

Mitochondrial __________ are similar to _________ which supports the __________

DNA, ribosomes, and tRNA are similar to Alpha-Proteobacteria, endosymbiotic theory

Alpha-Proteobacteria and Mitochondria divide similarly to _________ which supports the ____________

bacterial fission, endosymbiotic theory

Before the evolution of eukaryotes life was _________ and the environment was low in __________ and high in _______

anaerobic, O2, CO2/ N2

What event led to the evolution of eukaryotes? What created this event?

The great oxygenation event created by cyanobacteria releasing oxygen into the atmosphere

In the endosymbiotic theory it is said that an anerobic cell developed a

cell membrane and endomembrane system

In the endosymbiotic theory a Proto-eukaryotic cell engulfs

an aerobic Alpha-Proteobacteria

In the endosymbiotic theory the engulfed aerobic cell becomes

completely assimilated and loses the ability to leave the host

In the endosymbiotic theory the assimilated aerobic cell then becomes

a mitochondrion

Chloroplasts of plants and some protists originate from

a cyanobacteria symbiont

There are over ______ species of protists

100,000

Most protists are _____ but some are ________

unicellular, multicellular

Some protists have animal like _______ but others have plant like ________

plasma membranes, cell walls

Some protists are _____ towards other organisms

parasites

Protists usually reproduce ______ but some can also reproduce ________

asexually, sexually

Most protists exist in ________ environments

aquatic

For locomotion some protists use _______, while others use _________ or a ___________

cilia, flagellum, pseudopod

Some protists are __________ and get their energy from the ________ while others are ________ and must consume their nutrients by __________

photoautotrophs, sun, heterotrophs, phagocytosis

Protists are ________ meaning they have more than one common __________

polyphyletic, ancestor

Why were Eukaryotic “Supergroups” created and what does this have to do with Protist diversity?

Protists being polyphyletic and existing all over the phylogenetic tree led to scientists creating monophyletic “Supergroups” for all Eukaryotes

Describe the characteristics of the Supergroup SARS

Large variability in size, organization, and metabolism

What are the three major lineages of the SARS Supergroup?

Stramenophiles, Alveolates, and Rhizarians

Describe the characteristics of the Supergroup Archaeplastida

Have chloroplasts and are usually capable of photosynthesis, most members possess a cell wall and store food in the form of starch

Are are some major lineages from the Supergroup Archaeplastida?

Green algae and red algae

Most fungi are considered saprobes, which means that they use dead organic matter as a source of carbon

True

The term yeast is commonly used for unicellular Fungi

True

Fungi spores can be haploid or diploid and are used for sexual or asexual reproduction

False

During the stage known as plasmogamy two different nuclei will fuse, forming a diploid nucleus

False

In species belonging to the phylum Ascomycota, ascospores are used for asexual reproduction

False

All fungi are

heterotrophic

Many fungi possess a thick ______ made of ________ and _________

cell wall, chitin, glucans

Some fungi reproduce ______ but others can reproduce both __________

asexually, asexually and sexually

Most fungi are (cellular)

multicellular

Unicellular fungi are called

yeasts

Dimorphic fungi can switch between being

multicellular and unicellular

Mutualism

a relationship between organisms in which both organisms benefit

Parasitism

when an organism lives on or off of another organism (host) and benefits while causing the host eventual harm

Commensalism

a relationship between organisms in which one organism benefits and the other is neither harmed or bettered by the relationship