問題一覧
1
Consider the following statements about green algae. (I) Most green algae have two layers of cell wall. Inner layer is cellulose and outer layer is pectose and some compounds. (II) Algae of class Zygnematophyceae has a third layer of mucilage. (III) Major pigments are chlorophyll a and chlorophyll c. Xanthophyll pigments are absent in most. (IV) Pyrenoids are absent. (V) Food storage polymer is starch which is stored in chloroplasts as starch granules. (VI) Green algae have varying shapes of chloroplasts. How many of the above statements are true?
4
2
Which of the following is not a class of chlorophyta division?
Both charophyceae and zygnematophyceae
3
What is the direction of evolution in members of Volvocales?
Chlamydomonas to Volvox
4
What is the systematic position of chlamydomonas genus?
Chlorophyta division ➝ Chlorophyceae class ➝ Volvocales (or chlamydomonadales) order ➝ Chlamydomonadaceae family (unicellular) ➝ Chlamydomonas genus
5
Where is the eye spot or stigma located in Chlamydomonas?
Peripheral side of the chloroplast membrane
6
The common number and shape of chloroplast in chlamydomonas is
Single and cup shaped
7
With respect to chlamydomonas' pyrenoid, which of the following is correct?
There is a single pyrenoid covered by starch sheath
8
Flagellation in chlamydomonas is
Homokont: 2 equal apical
9
Blepharoplast is a modified
Centriole
10
In chlamydomonas, two equal flagella arises from two granules just above the contractile vacuole. These granules are
Blepharoplast
11
In chlamydomonas and in most algae, reproduction by which method shows that the environmental conditions are not dry and challenging
Asexual reproduction: Zoospores
12
Most species of chlamydomonas reproduce sexually where the reproductive strategy is
Isogamy: Both gametes motile
13
Which spore is diploid?
Zygospore
14
What is difference between oospore and zygospore?
Zygospore is formed when male gamete and female gamete fuse outside in the medium. Oospore is formed when male gamete and female gamete fuse inside the oogonium.
15
Consider the following statements about sexual reproduction in chlamydomonas. (I) When gametes unite then zygospore is formed and not oospore. (II) Life cycle of some chlamydomonas species is haplo-diplontic. Correct statements are?
I
16
Systematic position of volvox is
Chlorophyta division ➝ Chlorophyceae class ➝ Volvocales (or chlamydomonadales) order ➝ Volvocaceae family (motile colonial) ➝ Volvox genus
17
The cells in volvox colony (coenobium) are of type
Chlamydomonas type
18
Which of the following is not the feature of reproductive cell in a volvox colony?
It is multinucleated
19
Which of the following is not a feature of a typical cell in a volvox coenobium?
Cells are capable of producing zoospores
20
What is the arrangement of cells in the plakea stage of Volvox?
Incurved plate facing inward
21
In asexual reproduction of Volvox, the gonidium cell divides continuously and forms an inward curved plate of cell. The phialopore, before inversion, is present at?
Anterior side
22
What is the significance of phialopore in asexual reproduction of Volvox?
It helps in inversion of young coenobium
23
In asexual reproduction of Volvox, flagella is developed at what event?
Shortly after inversion
24
The sexual reproductive strategy of volvox is of which type?
Oogamous: Male motile and female non-motile
25
With regards to sexual reproduction in Volvox, consider the following statement (I) Gonidium is often not present in sexual colonies. (II) Oogonium doesn't resemble gonidium but antheridium does. (III) On maturity of oogonium, the antherozoids approach the egg through the neck of oogonium. (IV) The developing egg in oogonium is flagellated. (V) Antherozoids and eggs are developed by reductional division. Which of them are wrong?
Statements IV and V
26
With respect to sexual reproduction in Volvox, consider the following statements (I) The oogonium has only one egg (II) The oogonium cannot be distinguished from because it resembles gonidia. (III) After fertilization, the formed diploid cell will be covered in thick wall and is called zygospore. (IV) Oospore is spiny (V) Swarmer cell is haploid Correct statements are?
All except II and III
27
Life cycle of Volvox is
Haplontic
28
Which of the following is not a feature of order Oedogoniales?
Asexual reproduction happens by heterokont zoospores and akinetes.
29
What is the systematic position of this (unbranched) algae?
Chlorophyta division ➝ Chlorophyceae class ➝ Oedogoniales order ➝ Oedogoniaceae family➝ Oedogonium genus
30
Algae of oedogoniales are
Tychoplanktophytes
31
The members of genus oedogonium are?
Filamentous unbranched
32
The young filaments of oedogonium are attached to substrate. What is the nature of the basal cell of this filament?
It is devoid of chlorophyll
33
The structure which attaches oedogonium to the substrate is?
Holdfast
34
Which of the following is not describing the structure of oedogonium correctly?
The apical cell of the filament is conical
35
What is the shape of chloroplasts in oedogonium?
Reticulate
36
In cell division of oedogonium, ring formation happens at what position and by what?
Cell wall ruptures just beneath the upper septum of parent cell
37
In cell division of oedogonium, what forms the lateral walls of upper daughter cell?
Stretched Ring
38
In the cell division of oedogonium, what forms the apical cap and at where?
Upper part of ruptured cell wall forms apical cap at anterior end of upper daughter cell
39
In the cell division of oedogonium, which of the following events does not occur?
Ring stretches to form lateral walls of lower daughter cell
40
In the cell division of oedogonium, the younger cell is one which have?
More number of apical caps
41
The asexual zoospores in oedogonium are of type?
Stephanokontean Type
42
With respect to asexual reproduction in oedogonium by zoospores, which of the following statement is incorrect? (I) Zoospore is stephanokont (II) Every cell of oedogonium can act as zoosporangium except the holdfast. (III) The zoospore escapes when lateral walls of zoosporangium breaks. It is initially in a vesicle. (IV) Zoospore will swim freely and germinate to new individual while swimming. (V) Zoospore on its anterior side has a circular hyaline spot where blepharoplast granules, in close proximity with the necleus, are arranged and from each such granules, a flagellum rises which makes a circular arrangement of flagella. Thus this is called stephanokont zoospore. (VI) After swimming for sometime, the vesicle disappears and the zoospore settles on any substrate from its anterior side.
Only IV
43
Regarding sexual reproduction in Oedogonium, which of the following statements are incorrect? (I) It is oogamous (II) Sexual reproduction maybe of macroandrous or nonandrous type (III) All oedogonium are monoecious
III
44
Idiandrosporous species of oedogonium are
Nonnandrous dioecious species
45
What initiates the development of antheridia?
Division of an antheridial mother cell
46
How many antherozoids are produced in each antheridum of an Oedogonium filament?
2 haploid
47
In what aspects are antherozoids are dissimilar to asexual zoospores in Oedogonium?
Antherozoids are smaller and have fewer flagella around the circular hyaline spot
48
How does nonnandrous species of Oedogonium differ from macroandrous species of oedogonium?
Development of antheridia
49
What does the nannandrium consist of in Oedogonium?
One basal attaching cell and multiple antheridia
50
With respect to sexual reproduction in nonnandrous species of oedogonium oedogonium, some statements are given: (I) No antheridia forms in normal filaments of oedogonium. (II) Androsporangium produces haploid antherozoids. (III) Androspores are a type of akinetes (IV) Androspore germinates into dwarf male filaments on oogonium (V) Antheridia are seen only on dwarf male filaments How many of the above statements are correct?
3
51
The development of oogonia in macrandrous and nannandrous species of oedogonium is:
Identical
52
Oogonial mother cells divide to form:
One oogonium and one suffultory cell
53
What feature is always present at the upper end of an oogonium?
Both caps and hyaline spot
54
What is the purpose of hyaline spot of oogonium in Oedogonium?
To facilitate entry of antherozoids
55
What is the life cycle of Oedogonium algae?
Haplontic