Unit 2 Review

1
Unit 2 Review

• Biology 11
• S. Dosman

2
Explain binomial nomenclature and identify the
scientist who created this system.

• Carolus Linnaeus, a Swedish botanist designed a
  classification system based on an organisms
  physical and structural features. The more
  common structures organisms shared the more
  closely related they were.
• Organisms are all given a scientific name using
  Latin words. This provides a common language for
  all scientists regardless of their national
  origin. The names are commonly based on a
  particular characteristic of the organism such as
  color or habitat. An example of this would be
  Castor canadensis . This is the scientific name
  for a beaver Castor means beaver and canadensis
  means from Canada.
• A two part naming system uses the genus and
  species name to form the scientific name of the
  organism. The advantage is that the two part
  name can indicate similarities in anatomy,
  embryology and evolutionary history. For
  example, if two organisms share the same genus
  name than this indicates a close relationship
  Ursus horribilis (grizzly bear) and Ursus
  americanus (balck bear).

3
Identify the seven taxa used in taxonomy.

• The seven levels of taxa used in our current
  classification system are
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species.

4
Name the six kingdoms in our current
classification system.

• Eubacteria
• Archeabacteria
• Protista
• Fungi
• Plantae
• Animalia

5
What is a dichotomous key or classification key
used for?

• Biological keys are listings of specific
  characteristics grouped as paired statements and
  used by Biologists to classify organisms.

6
What are the two components of all viruses and
what is meant by the host range?

• Viruses are composed of an outer protein coat and
  a nucleic acid either DNA or RNA.
• Host range the limited number of host species,
  tissues, or cells that a virus or other parasite
  can infect.

7
What is a bacteriophage and what is the
difference between a temperate and a virulent
bacteriophage?

• A bacteriophage is a type of virus that infects
  bacteria in order to reproduce. As such, they are
  known as eaters of bacteria.
• Virulent phage a bacteriophage that causes the
  lysis of the host cell.
• Temperate phage a bacteriophage that does not
  cause the lysis of the host cell.

8
What are the four steps in the viral replication
cycle?

• Attachment There is chemical recognition and
  the virus attaches to the host cell. The virus
  invades the cell by injecting its DNA or RNA
  material into the cell and sometimes the entire
  virus will enter the host cells cytoplasm.
• Synthesis The DNA or RNA takes over the host
  cell and begins directing it to replicate the
  viral components such as proteins, nucleic acids,
  enzymes, and capsid proteins.
• Assembly The viral enzymes, proteins and
  nucleic acids are assembled to form new viruses.
• Release (and lysis) The host cell lysis (breaks
  open) and the new viruses are released. The host
  cell dies.

9
What is the difference between the lysogenic and
the lytic cycle?
Lysogenic cycle Lytic cycle
Does not kill host cell outright Kills host cell within minutes of infection
Viral genetic material integrates with hosts genetic material and replicates as host cell reproduces Viral genetic material is replicated by hijacking host cell.
Can lie dormant for years causing no apparent symptoms in host organism Causes symptoms in host organism as a result of lysis
For example a temperate phage replicates this way For example a virulent phage replicates this way
For example certain cancer-causing viruses replicate this way For example the common cold virus replicates this way
10
What are three major groups of Archaebacteria?

• The methanogens are bacteria that produce methane
  gas. 
• The thermophiles live in environments with
  extremely hot temperatures (up to 110C). 
• The halophiles live in environments that have a
  high salt content.

11
What three shapes are used to classify
Eubacteria?

• Eubacteria are classified based on three basic
  shapes.  There is spherical (plural cocci
  singular coccus), rod-shaped (plural bacilli
  singular bacillus) and spiral (plural spirilla
  singular spirillum)

12
What other trait is used to classify Eubacteria?

• Bacteria in the kingdom Eubacteria are often
  classified according to their modes of
  respiration and nutrition. 
• In terms of respiration they are classified based
  on whether or not they use oxygen. 
• In terms of nutrition they are classified based
  on how they obtain energy (autotrophs or
  heterotrophs).

13
Outline the difference between the following
obligate aerobes, obligate anaerobes and
facultative anaerobes.

• Obligate aerobes are bacteria that respire in the
  presence of oxygen. 
• Obligate anaerobes grow and respire in the
  absence of oxygen and can be found in deep soils,
  and marine and fresh water sediments.
• A facultative aerobe is a bacterium that can
  perform respiration either with or without
  oxygen.  This advantage allows them to adjust to
  a variety of environments.

14
Explain binary fission.

• Binary fission is asexual reproduction in
  bacteria. 
• The single strand of bacterial DNA replicates
  (copies) and the result is a copy for each new
  cell. 
• After the replication a cross wall begins to form
  and divides the bacterium into two separate
  bacteria. 
• They may separate or remain attached.

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16
What is an endospore?

• Some bacillus type bacteria have been able to
  survive very harsh conditions because of its
  ability to form an endospore. 
• A thick wall will form around the genetic
  material and a small amount of cytoplasm. 
• The rest of the cell disintegrates and the heat
  resistant endospore remains dormant until
  conditions become favorable again.

17
Identify some ways bacteria are useful to us.
Type of Bacteria Beneficial Effects
Clostridia Production of butanol and acetone from molasses
Acetobacter Production of vinegar from alcohol
Intestinal bacteria Food digestion synthesizing of vitamins in human
Lactobacilli Production of lactic acid from sugar
Aztobacter, nitrobacter Fixation of nitrogen in soils
Streptococci, lactobacilli Production of dairy products (cheese, yogurt)
Streptomyces Source of antibiotics (streptomycin and erythromycin)
18
What are antibiotics?

• Antibiotics are chemicals produced synthetically
  or by microorganisms that inhibit the growth of
  or destroy certain other microorganisms.
• They work by interfering with the metabolic
  processes of bacteria therefore killing the
  bacterium.

19
What are the basic characteristics organisms in
Kingdom Protista?

• Mostly microscopic and unicellular with some
  colonial or multicellular
• All eukaryotic (belong to Domain Eukarya)
• Can be heterotrophic or autotrophic
• Mostly aquatic, although some live in soil or
  inside a host.
• A protist is any eukaryotic organism that is not
  a plant, animal or fungus.

20
What are the three distinct groups of organisms
in kingdom Protista?

• Kingdom Protista is divided into three dinctinct
  groups. While they are not phyla, these divisions
  are widely accepted.
• Animal-like protists
• Plant-like protists
• Fungus-like protists

21
What are the characteristics of each group you
named.

• Animal-like Protists
• These organisms are often referred to as
  protozoans.
• They live primarily in aquatic habitats, although
  some can be found in the soil and the digestive
  tracts of animals.
• Some protozoans are parasitic.
• All are unicellular except for one.
• All are heterotrophs that ingest their food and
  perform intracellular digestion
• They are divided into phyla based on their method
  of locomotion.

22
What are the characteristics of each group you
named.

• Plant-like Protists
• Organisms in this group contain chloroplasts and
  are photoautotrophic.
• Includes all algae except for the blue greens.
• May be unicellular, multicellular or colonial.
• The multicellular marine algae, the seaweeds, are
  similar to marine plants and may be moved to the
  plant kingdom.
• Almost all are aquatic or they live in very damp
  terrestrial environments.

23
What are the characteristics of each group you
named.

• Fungus-like Protists
• Organisms in this group are unique in that they
  have both unicellular and multicellular stages.
• They are heterotrophic and perform extracellular
  digestion.
• They are decomposers and referred to as slime
  molds.
• The plasmodium is a well known slime mold.

24
What is the difference between endoplasm and
ectoplasm?

• Ectoplasm is a thin, watery cytoplasm near the
  plasma membrane of some cells and
• Endoplasm is a dense cytoplasm found in the
  interior of many cells

25
Outline a few differences between fungi and
plants.

• Plants are autotrophic (photosynthetic) and fungi
  are heterotrophic (decomposers).
• Plants have cell walls containing cellulose while
  fungi have cell walls containing chitin.
• Some fungi are parasitic.
• Fungi do not have chlorophyll.
• Plants have roots while fungi have mycelium.
• Plants reproduce using seeds while fungi use
  spores.

26
Identify the three divisions of Kingdom fungi and
a defining characteristic of each.
Division Characteristic Example
Mastigomycota Produce flagellated spores and contain cellulose in cell walls. Water moulds, chytrids
Amastigomycota Produce nonmotile spores and contain chitin in cell walls. Common moulds, yeasts, mushrooms
Deuteromycota Terrestrial sac and club fungi. Also known as imperfect fungi. Parasitic fungi and pathogenic fungi.
27
Explain symbiosis using lichen as an example.

• A symbiotic relationship is shared between two
  organisms and both benefit from the arrangement
  or interaction. 
• Lichens consist of a green photosynthetic partner
  and a heterotrophic fungal partner.  The
  photosynthetic partner is usually green algae and
  the fungus is normally a sac fungus. 
• The green algae provides and shares carbohydrates
  produced during photosynthesis with the fungus
  and the fungus provides carbon dioxide and water
  to the green algae for photosynthesis.

28
What is the difference between mycelium and
hyphae?

• The mycellium are a collection of microscopic
  branching filaments which are located on or below
  the surface of the substrate (what the fungi is
  attached to).
• The mycellium is made up of individual hyphae and
  they absorb nutrients.

29
Identify the basic characteristics of organisms
in kingdom Plantae

• Organisms within Kingdom Plantae are
  multicellular, eukaryotic, autotrophic and they
  lack mobility.
• Plants produce food via photosynthesis and have
  cell walls composed of cellulose.

30
Identify the four divisions of kingdom Plantae
and a defining characteristic of each.

• Non-vascular land plants do not contain any
  conducting tissues and are often referred to as
  bryophytes. These plants are small, grow close
  to the ground and include mosses and liverworts.
• Seedless vascular plants contain vascular
  tissues but do not produce seeds.
• Seeded vascular plants also contain extensive
  vascular tissue and the majority of species in
  the plant kingdom are in this group. They have a
  seeds that contain an embryo, a nutrient supply
  and a protective outer coat. There are 2 types,
  gymnosperms and angiosperms.
• Gymnosperms are non-flowering plants with seeds
  that do not develop within an enclosed structure
• Angiosperms are flowering plants with seeds that
  develop inside a protective structure.

31
What is the function of each of the following
plant structures rhizoids, xylem, phloem,
cuticle, and stomata.
STRUCTURE FUNCTION
RHYZOIDS Small hair-like or root-like Transport materials anchors plant
XYLEM Tubes made of dead cells Transport water from roots to rest of plant
PHLOEM Tubes made of living cells Transport glucose made via photosynthesis
CUTICLE Waxy covering on stem and leaves Prevent water loss
STOMATA Microscopic pores in leaves Gas exchange
32
Identify some characteristics used to classify
animals into phyla in Kingdom Animalia.

• Multicellular, Eukaryotic, Heterotrophic, Mostly
  motile (few exceptions) and Primarily sexual
  reproduction but some asexual.
• Asexual reproduction can be either budding or
  fragmentation.
• Sexual reproduction involves internal and
  external fertilization.

33
Name the nine phyla in Kingdom Animalia and give
one example of an organism from each phyla.

• Phylum Porifera sponges
• Phylum Cnidaria jellyfish
• Phylum Platyhelminthes tape worm
• Phylum Nematoda pinworm
• Phylum Annelidia earthworms
• Phylum Mollusca clams
• Phylum Echinodermata starfish
• Phylum Arthropoda ants
• Phylum Chordata birds, fish, frogs, bears

34
What are some reasons why arthropods are so
successful?

• Exoskeleton protection
• Body Segments
• Nervous System larger brains
• Nutrition process can obtain food in many ways
• Many feeding methods
• Small hiding, small spaces
• Movement quickly (3 pairs of legs)
• Mimicry (hide from predators)
• Hierarchical social system (roles)
• Life cycle reduces competition for food and
  living space

35
Name the six classes of vertebrate chordates
along with a defining characteristic and an
example of an organism from each class.

• Class Chondrichthyes Cartilaginous fish like
  sharks and rays
• Class Osteichthyes Bony fish like salmon, trout
  and tuna
• Class Amphibia Breathers in water and air like
  frogs
• Class Reptilia (creepers) Most live in dry, hot
  areas like snakes
• Class Aves Have feathers and hollow bones
  birds
• Class Mammalia Have hair, and mammary glands -
  mammals