Transition state structure of the substrate formed during an enzymatic reaction is
transient but stable
permanent but unstable
transient and unstable
permanent and stable
A phosphoglyceride is always made up of
only a saturated fatty acid esterified to a glycerol molecule to which a phosphate group is also attached
only an unsaturated fatty acid esterified to a glycerol molecule to which a phosphate group is also attached
a saturated or unsaturated fatty acid esterified to a glycerol molecule to which a phosphate group is also attached
a saturated or unsaturated fatty acid esterified to a phosphate group, which is also attached to a glycerol molecule
Pigment-containing memberanous extensions in some cyanobacteria are
heterocysts
basal bodies
pneumatophores
chromatophores
The complex formed by a pair of synapsed homologous chromosomes is called
equatorial plate
kinetochore
bivalent
axoneme
The three boxes in this diagram represent the three major biosynthetic pathways in aerobic respiration. Arrows represent net reactants or products
Arrows numbered 4, 8 and 12 can all be
NADH
ATP
H2O
FAD+ or FADH2
The most abundant intracellular cation is
Na+
Ca2+
H+
K+
D.
K+
The most abundant cation or positively charged ion in the extracellular fluid (ECF) is sodium (Na+). The most abundant anion or negatively charged ion in the ECF is chloride (Cl-). The most abundant cation in the intracellular fluid (ICF) is potassium (K+). Ca2+ plays an important role in signal transduction pathways. H+ is found in aqueous solution of all acids.
Which of the following criteria does not pertain to facilitated transport?
Requirement of special membrane proteins
High selectivity
Transport saturation
Uphill transport
The first stable product of fixation of atmospheric nitrogen in leguminous plants is
NO2-
ammonia
NO3-
glutamate