STD 11 - 10. Cell cycle and cell division — BIOLOGY STD 11 Science — Question

$(i)$ These muscle fibres taper at both ends and do not show striations.

$(ii)$ The wall of internal organs such as the blood vessels, stomach and intestine contain this type of muscle tissue.

$(iii)$ They are 'involuntary' as their function cannot be directly controlled.

$I$. sporophyte is multicellular, not free living but attached to the gametophyte for nourishment from it

$II$. some cells of the sporophyte undergo meiosis to produce haploid spores

$III$. these spores germinate to produce gametophyte

$R$ : It is synthesized in the posterior lobe of pituitary.

$\begin{array}{|p{0.6\linewidth}|p{0.3\linewidth}|} \hline Column\,\,I  & Column\,\,II \\ \hline a.\,\,Cellular\,\,level\,\,of\,\,organisation & 1.\,\,Cnidarians \\ \hline b.\,\,Organ\,\,level\,\,of\,\,organisation  & 2.\,\,Platyhelminthes \\ \hline c.\,\,Organ\,\,system\,\,level\,\,of\,\,organisation & 3.\,\,Chordates \\ \hline d.\,\,Tissue\,\,level\,\,organisation & 4.\,\,Porifera \\ \hline \end{array}$

$a\ \ b\ \ c\ \ d$