Identify the incorrect statement regarding algae:
1. At least a half of the total carbon dioxide fixation on earth is carried out by algae through photosynthesis.
2. Around 70 species of freshwater algae can be used as food.
3. Certain marine brown and red agae produce large amounts of hydrocolloids (water holding substances), e.g., algin (brown algae) and carrageen (red algae) which are used commercially.
4. Agar, obtained from Gelidium and Gracilaria are used to grow microbes and in preparations of ice-creams and jellies.
What is not true for red algae?
1. Lack centriole and flagella
2. Accessory pigments include phycocyanin, phycoeythrin and allophycocyanin
3. They reproduce using alternation of generation
4. The stored food is floridean starch very similar to cellulose
Identify the incorrect statement regarding green algae?
1. They contain chl a, chl b as well as carotenoids.
2. The chloroplasts may be discoid, plate-like, reticulate, cup-shaped, spiral or ribbon-shaped in different species.
3. Most members have one or more storage bodies called pyrenoids located outside the chloroplasts.
4. They usually have a rigid cell wall made of an inner layer of cellulose and an outer layer of pectose.
Consider the following statements regarding brown algae:
I. The pigments are chl a, c and xanthophylls, fucoxanthin
II. Storage food is laminarin and mannitol
III. The cellulosic cell wall is covered with algin
IV. They have a centrally located vacuole
V. Their photosynthetic organs are called as fronds - leaf like structures
VI. They have pear shaped biflagellate zoospores
VII. They have two unequal laterally attached flagella.
The number of correct statements is
Consider the following adaptations seen in plants:
I. Lack of cuticle
II. Presence of stomata for exchange of gases
III. Evolution of leaf
IV. Dominance of sporophyte
V. Structural support of vascular tissue
Which of the above adaptations would be required in a plant if it has to be successfully adapted to life on land?
1. All but I
2. All but I and III
3. I, II, III and IV
Identify the incorrect statement regarding mosses:
1. Leaves are one cell thick except at the midrib and lack stomata
2. The first gametophyte stage is protonema that is creeping and green
3. The second stage is the leafy stage, which develops from the secondary protonema as a lateral bud.
4. Rhizoids are elongated and unicellular
Consider the following statements regarding bryophytes:
I. Bryophytes are also called amphibians of the plant kingdom because they are depndent on water for sexual reproduction.
II. They play an important role in plant succession on bare rocks.
III. They lack true roots, stem or leaves.
IV. The sex organs in bryophytes are multicelluar.
V. They produce biflagellate zoospres.
VI. Archegonium is flask-shaped and produces a single egg.
The number of corrected statements is
Which of the following statements regarding gymnosperms are correct?
I. Ovules are naked - not enclosed by any ovary wall before fertilisation but seeds that develop after fertilisation are covered.
II. In all living Gymnosperms, sporophyte is dominant over the gametophyte.
III. They are heterosporous.
IV. The male and female gametophytes do not have an independent existence.
1. I, II and III
2. I, III and IV
3. II, III and IV
4. I, II, III and IV
Which of the following algae is likely to be found in the deepest waters?
(4) All are found at equal depths
Which pair[s] is/are in incorrectly matched?
I. Phaeophyceae - Algin in cell wall
II. Chlorophyceae - Laminarin is stored food
III. Rhodophyceae - 2, unequal, lateral flagella
(1) Only II
(2) Only III
(3) I and II only
(4) II and III only