At metaphase of mitosis, each chromosome consists of _______ chromatid(s) _______ centromere(s) ________ kinetochore(s) and _______ molecules of DNA:
(1) 2, 1, 2, 2
(2) 2, 2, 2, 2
(3) 2, 1, 1, 1
(4) 2, 1, 2, 1
In human cells chromosomes are:
(1) Always condensed during the entire cell cycle
(2) Different in different tissues
(3) Of the same size and shape
(4) Visible only during mitosis and meiosis
In prophase mitosis, which one of the following events occurs in animal cells but not in plant cells?
(1) Centrioles migrate to opposite sides of the nucleus
(2) Homologous chromosomes do not associate
(3) The nuclear envelope (membrane) breaks down
(4) Nucleoli disappear
Synaptonemal complex is more conspicious at:
(1) Zygotene
(2) Pachytene
(3) Diplotene
(4) Leptotene
Centrosomes are:
(1) Constricted regions of chromosomes
(2) Regions where microtubules polymerise
(3) Part of Cilia
(4) The central part of the same cell
Cellular structures which disappear during late prophase and reappear during telophase are:
(1) Mitochondria and spindle fibres
(2) Plasma membrane
(3) Nuclear membrane and nucleolus
(4) Plastid
Given:
1. Chromatid 2. Monad
3. Dyad 4. Daughter chromosome
The correct sequence in cell division is:
(a) 1, 2, 3, 4 (b) 2, 3, 1, 4 (c) 3, 2, 1, 4 (d) 4, 3, 2, 1
Cytokinesis in animal cell takes place by _______; in _______ direction while in plant cell by _______; in _______ direction:
(1) Furrowing, centrifugal, cell plate, centripetal
(2) Furrowing, centripetal, cell plate, Centrifugal
(3) Cell plate, centrifugal, furrowing, centripetal
(4) Cell plate, centripetal, furrowing, centrifugal
Liquid endosperm in coconut is resulted due to:
(1) Karyokinesis followed by cytokinesis
(2) Failure of karyokinesis followed by cytokinesis
(3) Karyokinesis twice followed by single cytokinesis
(4) Karyokinesis is not followed by cytokinesis
Label the structure indicated by lines (i), (ii), (iii) and (iv):
(1) (i) - Chromatid, (ii) Centriole, (iii) Centromere, (iv) Chromosome
(2) (i) - Chromomosome, (ii) Centriole, (iii) Centromere, (iv) Chromatid
(3) (i) - Chromatid, (ii) Centromere, (iii) Centriole, (iv) Chromosome
(4) (i) - Chromomosome, (ii) Centromere, (iii) Centriole, (iv) Chromatid