Midterm2- General protistology

Question 1

Morphology and movement

What are the 3 themes?

Answer 1

1. Protists are both organisms and individual cells, they solve their problems through structure and behavior 2. Protist biology breaks textbook rules 3. Importance of protists in ecosystems/human health

Question 2

Morphology and movement

Morphological types of protists

4

Answer 2

Flagalletes/ciliates/ameoba/cocci

Question 3

Morphology and movement

What is the difference between EUKARYOTIC flagella and cilia?

Answer 3

They are the exact same thing (not in bacteria tho)

Question 4

Morphology and movement

Definition: Flagalletes

Answer 4

Protists with 1 or more Flagella

Question 5

Morphology and movement

Definiton: Ciliates

Answer 5

Protists with MANY short flagella

Question 6

Morphology and movement

Definition: Amoebas

Answer 6

Protists with variable, dynamic cell shapes due to temporary cell protrusions “psudopods”

Question 7

Morphology and movement

Definition: Cocci

Answer 7

Protists with no Flagella and a fixed spherical or ellipsoidal cell shape

Question 8

Morphology and movement

What does the cytoskelaton do?

4 things

Answer 8

Gives structure/shape to the cell, supports flagella/psudopodia, intracellular trafficking and mitotic spindle/cell division

Question 9

Morphology and movement

What component of the cytoskelaton is involved in MiTOtic spindle?

Answer 9

Microtubules

MTOC

Question 10

Morphology and movement

What component of the cytoskelaton is involved in cell division

Answer 10

Microfillaments- contractile ring

Question 11

Morphology and movement

Microtubules features

Answer 11

Monomers- Alpha and Beta tubulin –> protofilament –> microtubules (13 pfs) POLAR = negative and positive (beta) end

Question 12

Morphology and movement

Microfillaments features

Answer 12

Actin –> Microfilaments, 1 type makes tightly bound rope, polar

not hollow

Question 13

Morphology and movement

What cytoskelaton component is most common in Ameobas?

Answer 13

Microfillaments

Question 14

Morphology and movement

What cytoskelaton component is most common in Flagalletes?

Answer 14

Microtubules (9 + 2)

Question 15

Morphology and movement

What is an Axoneme? What is its arrangement

Answer 15

The microtubular structure inside flagellum, 9 + 2

Question 16

Morphology and movement

What does 9 + 2 mean

Answer 16

9 pairs of Mts on the outside and 2 Mts on the inside, 1 complete pair (13 pt) and 1 incomplete (11)

Arrangement of Mts inside flagella (axenome)

Question 17

Morphology and movement

What is the Basal body/Kinetosome and what is its arrangement?

Answer 17

Microtubular structure at the BASE of the flagella, 9 + 0 type

Question 18

Morphology and movement

What is 9 + 0

Answer 18

9 triplets with nothing in the centre, 1 complete 2 not

Question 19

Morphology and movement

Cortical microtubular structures

(Flagellar roots)

Answer 19

Anchored to more Mts and other structures

Question 20

Morphology and movement

3 components of flagella

Answer 20

Axenome, basal body, cortical microtubular structures/flagellar roots

9 + 2, 9 + 0

Question 21

Morphology and movement

Opisthokonts

Flagella

Answer 21

RARE single flagella to generate propulsion

Question 22

Morphology and movement

What is the MTOC

Answer 22

Microtubule Organizing Centres: MTs emerge, assemble and are regulated here

Question 23

Morphology and movement

What is a Karyomastigont?

Answer 23

Flagella close to nucleus, Mitotic spindle (Mt) interacts with nucleus, basal body/MTOC arranges spindles

Question 24

Morphology and movement

What is the main function of Mastigonemes?

Stremenopiles have 1

Answer 24

To reverse the water flow, flagella then pull instead of push

Question 25

# Morphology and movement What is Cirri | Used in Euplotes

Answer 25

Bundles of cilia that are used like legs to walk on a substrate, have a specific gait | Used in Euplotes

Question 26

# Morphology and movement What is the undulating membrane? | trypnanosoma brucei in blood

Answer 26

Best for swimming in viscous fluids, moves like a sail/flag | Trypanosoma Brucei in blood

Question 27

# Morphology and movement What is phototaxis and who uses it?

Answer 27

Moving towards the light, euglena has specific organelle

Question 28

# Morphology and movement Kirbyana ## Footnote Excavata; parabasalia

Answer 28

Have intracellular axenomes

Question 29

# Morphology and movement What is the difference between Mts and Mfs

Answer 29

Mfs are thinner and not hollow, both have polarity. Mfs are best for contractillity and cell movement | (constriction ring during cell division)

Question 30

# Morphology and movement Lobopodia | Types of psudopods

Answer 30

Broad tube like psudopodia - supported by actin (Mfs)

Question 31

# Morphology and movement Filipodia | Types of psudopods

Answer 31

Very thin protrusions supported by actin (Mfs)

Question 32

# Morphology and movement Reticulopodia | Types of psudopods

Answer 32

Fused psudopodia that form elaborate networks supported by tubulin (Mts)

Question 33

# Morphology and movement Axopodia | Types of psudopods

Answer 33

Straight, long and on bending psudeopodia supported by tubulin (Mts)

Question 34

# Morphology and movement What are key features of actin/microfilaments?

Answer 34

Contractility and polymerization

Question 35

# Morphology and movement What is the endoplasm? | Amoeboid locomotion

Answer 35

Contains oragnelles, liquid & moves results in extensions of psudopods and uroid | INNER

Question 36

# Morphology and movement What is ectoplasm? | Ameoboid locomotion

Answer 36

Gel like and rigid | OUTER

Question 37

# Morphology and movement What 2 forces causes the flow of cytoplasm in ameobas? | Ameoboid locomotion

Answer 37

Polarity: In endoplasm mfs are aligned in a BUNDLE Contractility: In ectoplasm mfs arranged in a MESH that sqeeze cytoplasm from one end to another | bundle/mesh

Question 38

# Morphology and movement What 2 groups do not have flagella?

Answer 38

True fungi and Red algae

Question 38

# Skelatons and Buoyancy Endo/Exo skelaton definition

Answer 38

Endo: Inside or below the plasma membrane Exo: Outside the plasma membrane (sometimes called wall)

Question 38

# Skelatons and Buoyancy Cyto/Skelaton definitions

Answer 38

Cytoskelaton: precise term, conserved feature of ALL eukaryotes (mfs and mts) specific roles Skelaton: Everything that is NOT a cytoskelaton that supports cell, more vague and variable

Question 38

# Morphology and movement What is the most likely form of the LCA?

Answer 38

Flagallete- most dominant form across the tree and only 2 groups have lost this feature | Red algae, fungi

Question 38

# Skelatons and Buoyancy Organic skelaton | Composition based classification

Answer 38

Made up of organic molecules- proteins/polysaccharides synthesized by the cell

Question 39

# Skelatons and Buoyancy Calcareous Skelaton | Composition based classification

Answer 39

Made up of CaCO3 | Calcium carbonate

Question 39

# Skelatons and Buoyancy Siliceous Skelaton | Composition based classification

Answer 39

Made up of mostly SiO2 | Silica

Question 39

# Skelatons and Buoyancy Aggluntinated Skelaton | Composition based classification

Answer 39

Made up of foreign particles collected from the environment

Question 40

# Skelatons and Buoyancy What is the plant cell wall

Answer 40

An organic (made up of cellulose) exo (outside plasma membrane) skelaton

Question 41

# Skelatons and Buoyancy Microsporidia | Cysts and spores

Answer 41

Have a thick multilayer wall rich in CHITIN used to survive environmental stresses | Most examples are parasitic- live partly in environment/ partly in host

Question 42

# Skelatons and Buoyancy Resting environmental stages | Cysts and spores

Answer 42

Ciliates use complex resting environmental stages with organic walls in harsh conditions

Question 43

# Skelatons and Buoyancy What type of skleaton do Dinoflagalletes have?

Answer 43

Organic ENDO- cellulose plates assemble in alveoli under plasma membrane | **Theca**

Question 44

# Skelatons and Buoyancy What type of skelaton do Diatoms have?

Answer 44

Siliceous EXO- 2 overlapping valves outside the membrane | Frustrule

Question 45

# Skelatons and Buoyancy What type of skelaton do Coccolithophorids have? | Haptophytes

Answer 45

Calcareous EXO- Extracellular CaCo3 plates/scales | Coccoliths

Question 46

# Skelatons and Buoyancy What type of skelaton do Foraminferans have?

Answer 46

Calcareous EXO with reticulopodia, planktonic and large

Question 47

# Skelatons and Buoyancy What type of skelaton do radiolarians have?

Answer 47

Siliceous EXO- Common in water column

Question 48

# Skelatons and Buoyancy Name 3 marine sediments caused by skelatons?

Answer 48

Pink beach in Japan: Red formineferans Star sand: foraminferans White Cliffs of Dover: Coccolithophorid

Question 49

# Skelatons and Buoyancy How do these groups float? | Skelatons cytoplasm and organelles make them sink

Answer 49

HUGE Vacuoles: pumps out salt to make solution less dense than seawater | Cant do this in freshwater

Question 50

# Skelatons and Buoyancy Why are radiolarians poorly studied?? | 2 reasons

Answer 50

1. More common in open ocean 2. Hard to grow in a lab

Question 51

# Skelatons and Buoyancy Where do Acantharians live in the ocean? | Radiolarians

Answer 51

Near the surface, have photosyntetic algae living inside so need sunlight

Question 52

# Skelatons and Buoyancy Describe Acantharian spines | Radiolarians

Answer 52

10 pairs made up of Stronsium sulphate (SrSO4)

Question 53

# Skelatons and Buoyancy What type of skelaton does Acantharians have? | Radiolarians

Answer 53

ENDO- stronsium sulphate dissolves in sea water organic EXO- cortex above membrane

Question 54

# Skelatons and Buoyancy Describe Acantharian axopodia | Radiolarians ## Footnote Mts or Mfs?

Answer 54

Supported by MTs, each has an MTOC, expands and contracts

Question 55

# Skelatons and Buoyancy Describe Acantharians plasma membrane | Radiolarians

Answer 55

Surrounds cytoskelaton and skelaton | Endo skelaton

Question 56

# Skelatons and Buoyancy Describe Acantharians periplasmic cortex and central capsule | Radiolarians ## Footnote Endo or exo?

Answer 56

Organic (cellulose) exoskelaton with holes for spines/axopods to go through Central cortex is same but on inner side | Exo

Question 57

# Skelatons and Buoyancy Describe Acantharians Endoplasm | Radiolarians

Answer 57

Multiple nuclei found here, symboitic algae, other organelles

Question 58

# Skelatons and Buoyancy Describe Acantharians Ectoplasm | Radiolarians

Answer 58

Vacuoles are found here- where FEEDING happens, also threads and protrusions that expand and contract | feeding/movement

Question 59

# Skelatons and Buoyancy Describe Acantharians Myonemes | Radiolarians ## Footnote Mts or Mfs?

Answer 59

Contractile- made up of actin/Mfs, can raise plates over eachother | Purpose is to change volume/density or help food reach ectoplasm

Question 60

# Skelatons and Buoyancy How do Acantharians capture prey? | Radiolarians

Answer 60

Axopodia (Mts) are sticky and retract to move prey, hits cortex then ectoplasm | Kinteocysts (inside axopodia) make them sticky and help capture prey

Question 61

# Skelatons and Buoyancy Are radiolarians a monophyletic group? | Acantharians and Polycistenes

Answer 61

Most likely, polycistenes still have a small crystal of SrSO4 | vestigual organ = sign of evolution

Question 62

# Protist morphology and movement How did we know Parabasalians form a group before sequencing?

Answer 62

They all share a unique feature "Parabasal body"

Question 63

# Protist morphology and movement What can we say about relatedness and morphology?

Answer 63

Big flashy external features are generally adaptive and don't always say much about relatedness ex. Flagella/amoeba/cilia | Convergent evolution

Question 64

# Protist morphology and movement What is the Parabasal body? | Parabasalians ## Footnote Mf or mt?

Answer 64

Corresponds to Golgi, supported by thick cytoskelatal fibre (not mf or nt)

Question 65

# Protist morphology and movement What is the flagellar structure of Trichanomas? | Parabasalian ## Footnote 3 points

Answer 65

4 flagella with 4 basal bodies, Parabasal fibres connect to Parabasal body, fourth flagella is sideways and forms undulating membrane- supported by COSTA

Question 66

# Protist morphology and movement What is the Axostyle and Pelta | Trichanomas- Parabasalian ## Footnote Mts or Mf

Answer 66

Forms a hood- made up of MTs | Entirely unique structure but made up of familiar components

Question 67

# Protist morphology and movement What is the Karyomastignont? | Parabaslia

Answer 67

Nucleus, flagella, MTOC and other associated features (axostyle and pelta) are physically close to eachother | Replication happens in coordination

Question 68

# Protist morphology and movement What is Deltotrichonympha? | Parabasalian

Answer 68

Has 1 nucleus and thousands of flagella, when it replicates it sheds all but 4 flagella. This is a derived feature of ancestor