Protozoans

Question 1

Protozoans are a large, highly diverse, group of _________ organisms

Answer 1

Unicellular

Question 2

Basic characteristics of protozoans

• body
• reproduction
• habitat
• organelles

Answer 2

• unicellular organisms that occur as solitary, or colonial
• specialization of organelles has led to complexity in locomotion, nutritional modes, osmoregulation and behaviour
• asexual reproduction by fission and sexual reproduction
• found in moist environments, like soil, freshwater and marine habitats. Many commensal, mutualistic or parasitic

Question 3

4 groups of protozoans

Answer 3

Ciliated (ciliophora)
Apicomplexans (Sporozoans)
Amoeboid (Sarcodina)
Flagellated (Mastigophora)

Question 4

Ciliated protozoan characteristics

• locomotion
• nuclei
• reproduction
• lifestyle/ habitat

Answer 4

• cilia for locomotion and/or feeding
• two nuclei: macro and micro
• asexual reproduction by transverse fission and or budding
• sexual reproduction by conjugation
• free-living species in freshwater, marine and moist soil or parasites

Question 5

In what direction do Paramecium move?

Answer 5

• move against current

- cilia move in opposite direction backing it up a bit before moving forward

Question 6

Do paramecium have distinct anterior and posterior ends?

Answer 6

• yes, anterior is smaller and rounded

- posterior is cone shaped and larger

Question 7

Oral groove in paramecium

Answer 7

-depression on one side of the body. Extends from anterior end to middle. Serves to guide food particles into the gut (pharynx)

Question 8

Types of vacuoles in paramecium

Answer 8

• contractile: osmoregulation

- food vacuole: storage of food/ waste elimination

Question 9

Does paramecium have 2 nuclei?

Shape of nuclei?

Answer 9

Yes

Macro is kidney shaped and larger than micro nuclei

Question 10

Paramecium pellicle

Answer 10

-Rigid**, thin and and flexible firm membrane. Are elastic in nature and support cell membrane to help keep shape.

Question 11

Ciliature pattern of paramecium

Answer 11

Arranged in tufts called ciri. Move against current with a power stroke propelling then and a recovery stroke moving with current that doesn’t move then backward too much.

Question 12

Function of paramecium Trichocyst

Answer 12

Defence

Question 13

Why is binary fission considered to be asexual reproduction?

Answer 13

• only one cell involved

- no exchange of genetic material

Question 14

What is the plane of division during binary fission in paramecium?

Answer 14

Transverse

Question 15

What happens to the macro nucleus and the micro nucleus during binary fission

Answer 15

Macronucleus divides transversely amitotically (unevenly) by elongated and constricted in the middle

Micronucleus divides by mitosis into 2 daughter micronuclei which move to opposite ends of the cell

Question 16

Why is conjugation sexual reproduction?

Answer 16

-two different organisms and exchange of genetic material

Question 17

Which nucleus is involved in conjugation?

Answer 17

Micronucleus

Question 18

Shape of Vorticella sp. Macronucleus and general body

Answer 18

Horse-shoe shape

Funnel shaped with a stalk or in defence can construct and become more rounded

Question 19

Where are cilia in Vorticella?

Answer 19

Located at the mouth. Used for filter feeding and use cilia to grab food.

Question 20

Which specific structures in the stalk of Vorticella sp. allows for “popping” movement in Vorticella

Answer 20

Contractile myonemes/ fibers

Question 21

Shape of stentor and Macronucleus

Size of stentor

Answer 21

Snake like body and funnel shaped head (trumpet)

Macronucleus is many small, round pieces all in a line (macronuclear nodes)

0.5 mm

Question 22

Does stentor have anterior and posterior ends?

Answer 22

-anterior is funnel and posterior is the stalk

Question 23

Is the ciliate capable of changing its general shape through contention and extension in Stentor sp.?

Answer 23

Yes, can contract it’s head to hide mouth or extend body (stalk) to reach food

Question 24

Apicomplexans characteristics

• organelle arrangement
• life cycle

Answer 24

• have specialized arrangement of organelles called the apical complex at some point during life cycle
• life cycle include sexual stage plus one or more stages of asexual reproduction.
• all are parasitic

Question 25

How does a humans host become infected with plasmodium

Answer 25

Mosquito transfer sporozoites

Question 26

Where does asexual reproduction occur in the human host in Plasmodium sp.?

Answer 26

Liver/ blood cells

Question 27

Which lifecycle stage is infective to the mosquito host in Plasmodium?

Answer 27

Haploid sporozoite

Question 28

Where does Plasmodium fertilization occur?

Answer 28

In mosquitos gut

Question 29

Amoeboid protozoan locomotion

Answer 29

-use Pseudopodia for locomotion and/ or food capture

Question 30

Amoeba Proteus - general shape and size - type of Pseudopodia - does it have a test or is it naked? - reproduction?

Answer 30

- rounded, shapeless - lobopodia - naked amoeba (Gymnamoeba) - asexual binary fission or multiple fission in harsh environments

Question 31

How to differentiate food vacuoles and contractile vacuoles in amoebas…

Answer 31

- Contractile vacuoles are larger and transparent | - food vacuoles smaller and in greater number and have particles in them

Question 32

Why do amoebas have contractile vacuoles?

Answer 32

- maintains water balance (osmoregulation) | - protects cells from absorbing too much water, otherwise amoeba would burst

Question 33

Chaos (Pelomyxa) carolinesis differences and similarities to Amobea proteus

Answer 33

-larger More branched out Pseudopodia -may have 2 nuclei or thousands (multi-nucleated) - lobopodia - cytoplasmic streaming - no specific shape

Question 34

Entamoeba histolytica, a parasitic amoeba that causes _______ in humans. This amoeba is capable of forming a life cycle stage known as a _____

Answer 34

Amoebic dysentery Cyst: inactive, nonmotile, infected stage -cysts are infested and stomach/ duodenum cyst walls are digested away allowing trophozoites to be released. -protects from acidic environment

Question 35

Arcella sp. - shape and size - test and Pseudopodia - nuclei

Answer 35

- round, umbrella shaped, microscopic - test surrounds cell, Pseudopodia at test opening on underside. Test made of calcium carbonate - 2 nuclei, one on each side

Question 36

Globigerina so. Is a ____

Answer 36

Planktonic foraminiferan

Question 37

Globigerina sp. - test material - Pseudopodia type - how do these Pseudopodia differ from lobopodia

Answer 37

- Calcium carbonate - Reticulopodia - Thinner, protrude through pores in test, branched extensively to form sense networks

Question 38

Radiolarians - composition of test - type of Pseudopodia - how do these Pseudopodia differ from lobopodia

Answer 38

- silica - axopodia - microtubules supports, thin/spiky and many!!!

Question 39

Actinosphaerium sp. (a heliozoan) - can you differentiate endoplasm and ectoplasm - type of Pseudopodia do heliozoans possess

Answer 39

- yes, ectoplasm surrounds endoplasm | - axopodia

Question 40

Flagellated protozoa characteristics (mastigophorans) - locomotion - feeding style

Answer 40

- one or more flagella for locomotion | - includes autotrophic phytoflagellates, and heterotrophic species

Question 41

Euglena sp. - shape - flagella - stigma (eyespot) - pellicle?

Answer 41

- long, blunt/ round head with flagella - two flagella (one hidden in reservoir) - red dot at anterior end to detect light - yes, beneath outer membrane

Question 42

Movement of Euglena sp.

Answer 42

- quick, fish like movement - flagella not visible - very little shape change when moving

Question 43

Does Euglena belong to phytoflagellates or Zooflagellates?

Answer 43

Phytoflagellates | Has chloroplast

Question 44

Volvox sp. - shape - how do colonies form - why are these colonies included in protozoa

Answer 44

- round sphere - reproduce asexually through formation of auto colonies. Special cells divide to form daughter colonies that are smaller versions of the parents but with flagella onwards. Sexual colonies have reproductive cells called gonidia, which produce small daughter colonies that are released when mature. Sexual colonies develop ova+spermatozoa - they are individual cells that live together

Question 45

Volvox sp. - describe movement of colony - are flagella visible - are daughter colonies able to move - why green

Answer 45

- revolves in circles - flagella not visible in some views - doesn’t appear so - choloplasts

Question 46

Trypanosoma sp. are _____ parasites

Answer 46

Blood In vertebrates

Question 47

Trypanosoma sp. - what and where is kinetoplast - describe flagella - phyto or Zooflagellata

Answer 47

- specialized region of mitochondria that harbours most complex and inhaled mitochondrial DNA. Found near basal body (kinetosome) - one flagellum (part free, part attached) - Zooflagellates

Question 48

Trichonympha sp. lives where

Answer 48

Digestive tract of termites

Question 49

Trichonympha sp. - shape - flagella - why are termites dependent on them?

Answer 49

- bud shaped - many flagella (over 10000) - symbiotic relationship with termites, where they digest cellulose or termites die

Question 50

Ceratium sp. (dinoflagellate) - flagella - what type of covering - red tides

Answer 50

- two flagella (one longer sulcus and one shorter and horizontal girdle) - encased in sturdy cellulose plates - red tides are toxic to fish and crustaceans and accumulate in tissues of molluscs resulting in diarrhetic shellfish poisoning (human)