Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

Multiple choice biology body movements basics of joints joints and type of joints skeleton, joints and muscles

Major functions of skeleton are

  1. Support

  2. Protection

  3. Storage of ions

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

The skeleton serves a number of functions in vertebrates:

(1) The skeleton forms a rigid framework, which gives support to the body against gravity.
(2) The skeleton encloses the more vital organs of the body to protect them from injury.
(3) Bones contain deposits of calcium phosphate and calcium carbonate. These may be released into the blood if needed for use elsewhere in the body, but are later replaced. This helps in regulating calcium and phosphorus level of blood. 
So, the correct answer is option D.

Multiple choice biology body movements basics of joints joints and type of joints skeleton, joints and muscles

The brain is protected by the 

  1. Vertebrae

  2. Cranium

  3. Ribs

  4. Sternum
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  • The skull is composed of two parts: the cranium and the mandible.
  •  In the human, cranium has two parts the neurocranium and the viscerocranium. 
  • The neurocranium forms the cranial cavity that surrounds and protects the brain and brainstem. 
  • The neurocranium consists of the occipital bone, two temporal bones, two parietal bones, the sphenoid, ethmoid, and frontal bones—all are joined together with sutures. Hence, The brain is protected by the Cranium.
So, the correct answer is 'Cranium'.

Multiple choice biology structure of chromosome, cell cycle and cell division cell division in embryo development mitosis division for growth and reproduction

The method of reproduction in unicellular organisms like amoeba and bacteria in which they split into two equal halves and produce new ones is called ............

  1. Fragmentation

  2. Binary fission

  3. Budding

  4. Spore formation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In binary fission, parent cell divides into two equal halves called daughter cells. Daughter cells are identical to each other and to their parent cell. Organisms like the amoeba, bacteria, euglena, etc. exhibit binary fission. During multiple fission, the organism divides itself into numerous daughter cells.

So, B is the correct option.

Multiple choice biology structure of chromosome, cell cycle and cell division cell division in embryo development mitosis division for growth and reproduction

In animal cells, cytokinesis involves 

  1. Separation of sister chromatids

  2. Contraction of ring of microfilaments

  3. Depolymerisation of kinetochore microtubules

  4. Protein kinase that phosphorylates other enzymes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During cytokinesis in animal cells, a contractile ring composed of actin microfilaments and myosin forms beneath the plasma membrane. The constriction of this ring pinches the cell into two daughter cells.

Multiple choice biology structure of chromosome, cell cycle and cell division cell division in embryo development mitosis division for growth and reproduction

In animal cytokinesis, cleavage occurs with the help of

  1. Microtubules

  2. Spindle fibres

  3. Microfibrils

  4. Microfilaments
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In animal cells, cytokinesis is achieved by the formation of a contractile ring composed of actin microfilaments, which pinches the cell membrane inward.

Multiple choice biology structure of chromosome, cell cycle and cell division cell division in embryo development mitosis division for growth and reproduction

Cytochalasin B is a drug isolated from moulds. It blocks the formation of contractile microfilaments. Which of the following aspects of the cell cycle would be most disrupted due to this ?

  1. Cleavage furrow formation

  2. Attachment of kinetochore to spindle fibres

  3. Spindle fibre formation

  4. Cell elongation during anaphase
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Spindle formation is mainly done by centrioles. It helps in separation of chromosomes during cell division. Cytochalasin B is a cell-permeable mycotoxin. It inhibits cytoplasmic division by blocking the formation of contractile microfilaments due to which cell is unable to maintain the desired number of chromosomes and leads to numerical abberations.

Multiple choice biology environmental science plant adaptation adaptation in plants plant habitat

The bats are able to fly in dark since their mouth produce?

  1. Sound waves

  2. Ultrasonic waves

  3. Infrared rays

  4. Ultraviolet rays
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bats navigate and locate obstacles or prey in total darkness by emitting high-frequency ultrasonic waves and listening to the returning echoes. This biological sonar system is known as echolocation.

Multiple choice biology environmental science plant adaptation adaptation in plants plant habitat

The bats are able to fly in dark since their mouth produce

  1. Sound waves

  2. Ultrasonic waves

  3. Infrared rays

  4. Ultraviolet rays
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Every night a bat puts in 600-700 kilometres of airtime. Flying low, the animals catch insects at speeds of around 40 metres per second. At night the bat uses its hearing to navigate its way to prey. Bats catch insects continuously using echolocation, an advanced navigation system. The bat emits ultrasonic waves with very high frequencies. Its calls are pitched at 20-100 kilohertz, a frequency that is too high-pitched for humans to hear naturally. Their sounds are reflected in the environment, hitting various objects and returning to the bat as echoes. The echo signals enable the bat to form a mental map of its surroundings.
So the correct option is 'ultrasonic waves'.