Heartwood differs from sapwood in
Presence of rays and fibres
the absence of vessels and parenchyma
having dead and non-conducting elements
having dead and non-conducting elements
C.
having dead and non-conducting elements
As a result of continued secondary growth in subsequent years, the older part of secondary xylem or wood becomes non - functional as it loses the power of conduction. The cells of this wood are filled with resins or tennis produced by adjacent functional, secondary xylem becomes hard, durable and blackish in colour, called heartwood, Now, the function of secondary xylem( water and mineral conduction from roots) is performed by outer younger-rings of xylem, which is called sapwood.
In vitro fertilisation is a technique that involves the transfer of which one of the followings into the Fallopian tube?
Embryo only, up to 8 cells stage
Either zygote or early embryo up to 8 cell stage
Embryo of 32 cells stage
Embryo of 32 cells stage
C4 plants are more efficient in photosynthesis than C3 plants due to
higher leaf area
the presence of a larger number of chloroplasts
the presence of thin cuticle
the presence of thin cuticle
The genetically - modified (GM) brinjal in India has been developed for
insect - resistance
enhancing self- life
enhancing mineral content
enhancing mineral content
Coiling of garden pea tendrils around any support is an example of
thigmotaxis
thigmonasty
thigmotropism
thigmotropism
Sertoli cells are found in
Ovaries and secrete progesterone
adrenal cortex and secrete adrenalin
seminiferous tubules and provide nutrition to germ cells
seminiferous tubules and provide nutrition to germ cells
Consider the following four statement (1-4) regarding kidney transplant and select the two correct ones out of these
1) Even if a kidney transplant is proper the recipient may need to take immuno- suppressants for a long time
2)The cell-mediated immune response is responsible for the graft rejection
3) The B-lymphocytes are responsible for rejection of the graft
4) The acceptance of rejection of a kidney transplant depends on specific interferons
The two correct statements are
(2) and (3)
(3) and (4)
(1) and (3)
(1) and (3)
Which one of the following cannot be explained on the basis of Mendel's Law of Dominance?
the discrete unit controlling a particular character is called a factor
Out of one pair of factors, one is dominant and the other recessive
Alleles do not show any blending and both the characters recover as such in F2 generation
Alleles do not show any blending and both the characters recover as such in F2 generation
Which stages of cell division do the following figures A and B represent respectively?
Metaphase - Telophase
Telophase - Metaphase
Late anaphase - Prophase
Late anaphase - Prophase
