Which one of the following components of urine in a healthy human does not differ much in concentration from that of blood plasma?
NH4 +
K+
Na+
SO4 2-
D.
SO4 2-
SO4 2-, creatinine and other metabolic end products are the non-threshold substances which are not at all reabsorbed and are excreted in urine even under normal conditions. This is the reason these substances do not differ much in concentration from that of blood plasma.
Na+, K+, glucose and Ca2+ are the high-threshold substances, which are reabsorbed very extensively and do not appear in urine under normal conditions. These appear in urine only if their concentration in plasma is abnormally high or in renal diseases when reabsorption is affected. NH4 + is excreted in the form of urea.
The apoplast is located
outside the plasma membrane
in the entire cytosol
on both sides of plasma membrane
in the plastidial content
The aleurone synthesises and secretes digestive enzymes that hydrolyse nutrients stored in the endosperm, in the presence of
auxin
gibberellin
cytokinin
ethylene
ATP synthesis in cell requires
H+ gradient across the membrane
K+ gradient across the membrane
PO4 3- gradient across the membrane
Ca2+ gradient across the membrane
Which one of the following acts solely as an inhibitory neurotransmitter?
Norepinephrine
Gamma () amino butyric acid
Acetylcholine
Dopamine
Which one of the following is called intra-specific chemical messenger?
Pheromones
Prostaglandins
Corticotrophin
Catecholamines
Which one of the following secretes glucagon?
Beta () cells of islets of Langerhans
Alpha () cells of islets of Langerhans
Acidophilic cells of adenohypophysis
Basophilic cells of adenohypophysis
Osteoid refers to
the smallest bone of the body
young hyaline matrix of true bone in which calcium salts are deposited
membranous ossification of cranium
the largest bone of the body