The annular and spirally thickened conducting elements generally develop in the protoxylem when the root or stem is
maturing
elongating
widening
widening
C.
widening
Vessel or tracheae are made up of a row of cells, placed one above the other, with their intervening walls absent or variously pored. The walls of vessels are lignified and hard, but not very thick. The cell cavity or the lumen is wide. The thickening may be annuler, spiral, scalariform, reticulate and pitted.
Which part of human brain is concerned with the regulation of body temperature?
Medulla oblongata
cerebellum
cerebrum
cerebrum
Middle lamella is mainly composed of
hemicellulose
muramic acid
calcium pectate
calcium pectate
The genetic defect-Adenosine Deaminase (ADA) deficiency may be cured permanently by
periodic infusion of genetically engineered lymphocytes having functional ADA cDNA
administering denosine deaminase activators
introducing bone marrow cells producing ADA into cells at early embryonic stages
introducing bone marrow cells producing ADA into cells at early embryonic stages
In a standard ECG, which one of the following alphabets is the correct representation of the respective activity of the human heart?
R-repolarisation of ventricles
S- start of systole
T -end of diastole
T -end of diastole
Plasmodesmata are
lignified cemented layers between cells
locomotory structures
membranes connecting the nucleus with the plasmalemma
membranes connecting the nucleus with the plasmalemma
If a live earthworm is pricked with a needle on its outer surface without damaging its gut, the fluid that comes out is
excretory fluid
coelomic fluid
haemolymph
haemolymph
Which one of the following are the correct pairing of a body part and the kind of muscle tissue that moves it?
Heart wall - Involuntary unstriated muscle
Biceps of upper arm - smooth muscle fibres
Abdominal wall - Smooth muscle
Abdominal wall - Smooth muscle
In barley stem, vascular bundles are
open and scattered
closed and scattered
open and in a ring
open and in a ring
