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Flashcards in Midterm - Q&A Deck (28):
1

In the hierarchal system used for algal identification, Classes are subdivided into ____.

Orders

2

____ is one group of algae that can produce toxins.

Cyanobacteria
Diatoms

3

It is now believed that the eukaryotic chloroplast developed by the process of ____.

Endosymbiosis

4

The thallus of a brown alga such as kelp has a(n) _____ to help in anchoring it to a surface.

Holdfast

5

The _____ phase in a batch culture occurs when the growth rate equals the mortality rate.

Stationary

6

Ralph Lewin is well-known among algal biologists for ____.

Discovering Prochloron, an intermediate form between prokaryotes and eukaryotes

7

Cyanophyta
A) cell covering
B) storage product
C) Diplontic lifecycle (yes, no, maybe)

A) cell wall of muramic acid
B) cyanophycean starch
C) no

8

Bacillariophyceae
A) cell covering
B) storage product
C) Diplontic lifecycle (yes, no, maybe)

A) frustule made of silica
B) chrysolaminarin
C) yes

9

Synurophyceae
A) cell covering
B) storage product
C) Diplontic lifecycle (yes, no, maybe)

A) scales
B) chrysolaminarin
C) no

10

Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
Epilithic / Epiphytic

Epilithic algae grow attached to rocks whereas epiphytic algae grow attached to other plants.

11

Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
Pennate / Centric

Pennate diatoms are bilaterally symmetric, usually with a raphe or pseudoraphe, and one or two chloroplast. Centric diatoms are radially symmetric, no raphe, and one to many chloroplasts.

12

Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
Tinsel / Whiplash

A tinsellated flagellum is hairy and longer, whereas a whiplash flagellum is smooth with fine hairs or no hairs at all and much shorter. The tinsellated flagellum is used for motility and capture of prey, whereas the whiplash flagellum is not involved in motility but does help the tinsellated one to bring in the prey closer to the cell before being phagocytosed.

13

Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
Colony / Coenobium

A colony is an aggregation of a varying number of individual cells whereas a coenobium is a type of colony where there are a fixed number of cells (usually in multiples of 2, 4, 16...).

14

Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
Zoospore / Aplanospore

A zoospore is a motile, asexual reproductive structure whereas an aplanospore is a nonmotile, asexual reproductive structure.

15

Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
True branching / False branching

True branching occurs as a result of cell division in a second plane whereas false branching occurs (usually in Cyanobacteria) due to aggregation of two filaments, sometimes at a dead cell and are joined together by mucilage.

16

Describe anoxygenic.

A process where oxygen is NOT produced, for example, Photosystem I.

17

Describe mesokaryotic.

A type of algae thought to be an intermediate between prokaryotes and eukaryotes in which the chromosomes are large, with little or no histone protein, there is no interphase during mitosis division and the nuclear membrane persists.

18

Describe BMAA.

Betamethyl-L-alanine is a neurotoxin produced by Cyanobacteria that form symbionts with the cycad roots from Guam. It is thought to biomagnify in food webs and cause neurodegenerative diseases in human patients with Alzheimer’s disease or Parkinson’s disease.

19

Describe phagotrophy.

A method of feeding used by some heterotrophic algae (and other organisms) in which living or non-living particles are engulfed and brought into the cell through endocytosis. The cell’s membrane makes an infolding to form a vesicle, then the cell digests the material.

20

Describe oligotrophy.

A nutrient-poor water body where centric diatoms and other algae can be found in.

21

Describe pseudoparenchymatous.

A complex, three-dimensional aggregation of cells in which individual linear filaments may still be distinguished.

22

What are some features common to ALL members of the Division Chromophyta?

-heterokontous flagella at some point in lifecycle
-fucoxanthin as a common accessory pigment
-stacked thylakoids in chloroplasts
-chrysolaminarin as the storage product for photosynthate
(note that fucoxanthin is not found in all chromophytes)

23

This statement is false. Rewrite it to make it true.
Diatoms are the only algae capable of fixing nitrogen.

Cyanobacteria are the only algae capable of fixing nitrogen.

24

This statement is false. Rewrite it to make it true.
Dinoflagellates are protected from herbivores by their covering of cellulose plates.

Dinoflagellates are not protected from herbivores by their covering of cellulosic plates.

25

This statement is false. Rewrite it to make it true.
An auxotrophic alga switches between autotrophy and heterotrophy depending on environmental conditions.

A mixotrophic alga switches between autotrophy and heterotrophy depending on environmental conditions.

26

This statement is false. Rewrite it to make it true.
The purpose of sexual reproduction in algae is to create genetic diversity.

The purpose of sexual reproduction in algae is to resist environmental change and to regain proper size (asexual reproduction causes diatoms to shrink 1/2 the size of the parent).

27

This statement is false. Rewrite it to make it true.
The light microscope greatly improved our understanding of algae by allowing us to see cellular ultrastructure.

The transmission electron microscope greatly improved our understanding of algae by allowing us to see cellular ultrastructure.

28

What is mucilage and why do algae produce it?

-composed of water, sugar and proteins
-creates a clear slime
-used in false branching Cyanobacteria to link two branches not physically attached to each other
-allows cells to stick to each other in colonies
-protects algae from desiccation
-allows for algae to sink slower, provides buoyancy
-dissuades herbivores