Biology MCQs

Notes:
A plant cell wall is arranged in layers and contains cellulose microfibrils, hemicellulose, pectin, lignin, and soluble protein. Plant cell walls are primarily made of cellulose, which is the most abundant macromolecule on Earth.

Notes:
The thermoregulatory center in the hypothalamus controls the temperature at which the human body operates. There are two sets of thermoreceptors involved in the controlling of the body temperature.

Notes:
There are 13 essential nutrients required by plants for its healthy and proper growth. Now these nutrients are divided into two categories:
Macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulphur)
Micronutrients (iron, copper, manganese, zinc, boron, molybdenum and chlorine)
Additional mineral nutrient elements which are beneficial but not necessary are sodium, cobalt, vanadium, nickel, solenium, aluminium and silicon. Thus boron, zinc and copper falls into category of essential micronutrients while sodium does not.
 

Notes:
Mycoplasma is a genus of bacteria that do not have a cell wall surrounding the cell membrane.

Notes:
Splanchnology is the study of the visceral organs, i.e. digestive, urinary, reproductive and respiratory systems.

Notes:
Jan Ingenhausen is a Dutch-born British physician and scientist, best known for his discovery of the process of photosynthesis, by which green plants absorb carbon dioxide and release oxygen in sunlight.

Notes:
Those organisms which can live on both land and water are called amphibians. Some examples of amphibians are frogs and toads, newts, salamanders and caecilians.

Notes:
Archaebacteria are primitive bacteria that have a cell wall consisting of branched lipids that help them to endure adverse conditions.

Notes:
Chromatin is a complex of DNA and proteins that make up chromosomes within the nucleus of eukaryotic cells.

Notes:
Blue-green algae or cyanobacteria are prokaryotes. They lack membrane bound organelles and a nucleus.