Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

Multiple choice biology movement and locomotion in man locomotion in animals bones and movements muscle contraction

Cockroaches have an outer skeleton.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
An exoskeleton is the external skeleton that supports and protects an animal's body. Examples of animals with exoskeletons include insects such as grasshoppers and cockroaches, and crustaceans such as crabs and lobsters.
Cockroaches are winged insects found in nearly every part of the world. Like most other insects, cockroaches have an exoskeleton, meaning their skeleton is located on the outside of their bodies. They have three simple body parts: the head, thorax, and abdomen.
Hence, the answer is true.
Multiple choice biology skeleton and movements locomotion in animals bones and movements muscle contraction

EDTA injected into muscles combines with $Ca^{2+}$ and

  1. Stops contraction

  2. Causes contraction

  3. Slows down contraction

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Active sites for myosin are present on actin which are masked by troponin in resting state. When  Ca++ level increases it leads to the binding of calcium with a subunit of troponin on actin(thin) filaments and thereby remove the masking of active sites for myosin.
  • Utilizing the energy from ATP hydrolysis, the myosin head now binds to the exposed active sites on actin to form a cross bridge. 
  • This pulls the attached actin filaments towards the centre of ‘A’ band.
  •  The ‘Z’ line attached to these actins are also pulled inwards thereby causing a shortening of the sarcomere, i.e., contraction.
  • When EDTA  injected into muscles combines with Ca ++ and prevents the binding of calcium with troponin and slows down contraction.
  • So, the correct answer is 'Slows down contraction'. 
Multiple choice biomacromolecules biotechnology cell biology and biotechnology biomolecules biology

An organic compound has a triple bond and double bond. It can be tested by :

  1. Bromine water

  2. Beyer's reagents

  3. Fehling's solution
  4. Ammonical $AgNO _3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The bromine test is a qualitative test for the presence of unsaturation (carbon-to-carbon double or triple bonds) and phenols. An unknown sample is treated with a small amount of elemental bromine in an organic solvent, being as dichloromethane or carbon tetrachloride. Presence of unsaturation and/or phenol in the sample is shown by disappearance of the deep brown coloration of bromine when it has reacted with the unknown sample. 
So, the correct option is 'Bromine water'.

Multiple choice biomacromolecules biotechnology cell biology and biotechnology biomolecules biology

What is common between NAD and FAD?

  1. Both are coenzymes

  2. Both are derived from proteins

  3. Both acts as oxygen carriers

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nicotinamide Adenine Dinucleotide (NAD) and Flavin Adenine Dinucleotide (FAD) are coenzymes associated with reversible oxidation and decrease reactions. Then, these lessened coenzymes can give these electrons to some other biochemical response ordinarily engaged with a procedure that is anabolic (like the union of ATP).

So, the correct option is 'Both are coenzymes'.

Multiple choice biomacromolecules biotechnology cell biology and biotechnology biomolecules biology

Match and choose the true option.

  1. $NaCl$ - Inorganic micromolecule
  2. ${H} _{2}O$ - Organic micromolecule

  3. Starch - Organic micromolecule

  4. Glucose - Inorganic macromolecule
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Organic molecules are made of chains of carbon atoms. Inorganic molecules are minerals like salts NaCl which held together by an ionic bond.
Water doesn't contain any carbon atom in its molecule.  So water is an inorganic compound. 
So the correct answer is A.