Unicellular Eukaryotes Protozoan Groups Ch11

Question 1

synapomorphy

Answer 1

characters shared by a group of taxa due to their inheritance from a common ancestor

Question 2

11.1 Describe the synapomorphies that define eukaryotes?

Answer 2

membrane bound nucleus
endosymbiosis = organelles (e.g, mitochondria)
-in the presence of a nucleus and organelles

Question 3

What is a protozoan?

Answer 3

Unicellular eukaryotes with animal-like characteristics- some have chloroplast

Question 4

What is the body plan of a protozoan?

Answer 4

unicellular
-No cell wall
– Locomotion
– Nutrition in many ways including autotrophic & heterotrophic
– Mutualistic, commensalistic, parasitic

Question 5

What are the general features of a protozoan?

Answer 5

*Nucleus- contains genetic material
* Mitochondria (energy; requires O2)
* Golgi apparatus (aka dictyosomes)
– Secretory function
– Intracellular digestion
* Plastids (contain photosynthetic pigments)
*Extrusomes (organelles that extrude things)
– Trichocyst (eject threads)
– Toxicyst (eject filaments with toxins)

Question 6

Ameboid (pseudopodia)

Answer 6

Outer layer of gel-like ectoplasm surrounds inner, more fluid,
endoplasm
Hydrostatic pressure of endoplasm pushes against ectoplasm

Question 7

ciliary & flagellar
movement
Sliding Filament Hypothesis:

Answer 7

Sliding Filament Hypothesis:
1. Dynein arms bind to tubulin subunit
2. Bend to move tubulin subunit up
3. Release and bind to subunit below
4. Repeat rapidly; then reverse
5. Result = bending of cilia or flagellum

Question 8

what are the three types of Pseudopodia and what they are?

Answer 8

• Lobopodia – large with ectoplasm & endoplasm
• Filopodia – thin extensions of ectoplasm
• Axopodia – thin, supported by axial rods of microtubules

Question 9

Pseudopodia
Engulf food particles via ________ to form food vacuole

Answer 9

phagocytosis

Question 10

Contractile vacuole

Answer 10

expels excess liquid on contraction
-used for osmoregulation

Question 11

Pellicle

Answer 11

flexible proteinaceous strip under the cell membrane

Question 12

Trichocyst

Answer 12

a structure in the cortex of certain ciliate and flagellate protozoans consisting of a cavity and long, thin threads that can be ejected in response to certain stimuli

Question 13

What are the four types of Asexual Reproduction?

Answer 13

Binary fission
Budding
Schizogeny
Sporogeny

Question 14

Binary fission

Answer 14

separation of the body into two new bodies

Question 15

Budding

Answer 15

a new individual develops from some generative anatomical point of the parent organism
- progeny smaller than adult

Question 16

Schizogeny

Answer 16

form multiple individuals

Question 17

Sporogeny

Answer 17

-multiple fission preceded by union of gametes (form
spores or sporozoites)

Question 18

11.7 Describe ways in which sexual reproduction occurs in protozoans.

Answer 18

Form haploid gamete cells or gamete nuclei
– Syngamy = one gamete fertilizes another
– Autogamy = gametes arise and fuse within the parent
– Conjugation = exchange gametic nuclei