Tag: biology

Questions Related to biology

................. part of the blood carries minerals, vitamins, sugar and other foods to the body's cells.

biology simple nutrients into cells blood and its components components of blood composition of blood

  1. Plasma

  2. Platelets

  3. Red blood corpuscles

  4. White blood corpuscles

Show answer
Correct Option: A
Explanation:

Blood is made up of plasma and corpuscles. Plasma is the pale coloured extracellular fluid that holds the blood cells. 55% of the body's total blood volume is plasma. It contains mostly water (up to 95% by volume), and dissolved proteins, glucose, clotting factors, electrolytes, hormones and carbon dioxide and helps in transportation. Whereas platelets, RBC and WBC do not carry minerals, other food to the body cells. Thus, option A is correct.

Which of the above statements is correct and which are false?
(1) Plasma constitutes 45% of the human blood.
(2) Albumin is a plasma protein, which helps in osmotic balance.
(3) Factors responsible for the blood clotting process are present in the blood.
(4) Plasma without clotting factors is called serum.
(5) Minerals are not generally found in blood.

biology simple nutrients into cells blood and its components components of blood composition of blood

  1. Only 5 is wrong and all others 1 to 4 are correct.

  2. 1 and 2 are correct and 3, 4 and 5 are wrong.

  3. 2 and 4 are correct and 1, 3 and 5 are wrong.

  4. 1 and 5 are correct and 2, 3 and 4 are wrong.

  5. 2, 3 and 4 are correct and 1 and 5 are wrong.

Show answer
Correct Option: E
Explanation:

Plasma is the pale yellow colored component of blood that makes up for 55% of the bloods total volume. The plasma though it is made up of 95% water it contains proteins such as albumins. The anticoagulant are present in the blood itself.  Blood serum is blood plasma without the coagulant factors.

The given table shows the result of intravenous injection of substances to determine the effect of each substance on normal body variables. Appropriate amount of time was allowed between injections and the substances did not interfere with one another. 

Variable Baseline values Values after injecting substance A    Values after injecting substance B Values after injecting substance C Values after injecting substance D
Serum ${ Ca }^{ ++ }$ 2.3mmol/L 2.3mmol/L 2.3mmol/L 3.0mmol/L 2.3mmol/L
Serum ${ Na }^{ + }$ 135mmol/L 135mmol/L 135mmol/L 136mmol/L 138mmol/L
Serum glucose 5.6mmol/L 3.3mmol/L 5.6mmol/L 7.4mmol/L 5.6mmol/L

Which one of the following change in variable values is insignificant?

biology simple nutrients into cells blood and its components components of blood composition of blood

  1. The change in serum glucose when substance A is injected.

  2. The change in serum ${ Na }^{ + }$ when substance D is injected.

  3. The change in serum ${ Ca }^{ ++ }$ when substance C is injected.

  4. The change in serum glucose when substance C is injected.

  5. The change in serum ${ Na }^{ + }$ when substance B is injected

Show answer
Correct Option: E
Explanation:

The process by which the human body controls the internal ennvironment is known as Homeostasis . The addition  or presence of any variable tends to regulate the concentration of  any substance or   body temperature towards a constant.   examples of this homeostasis is seen in Human body wherein there is a regulation of the body temperature, concentration of Na+, Ca++ ions and glucose levels in blood plasma.   According to the given table showing the intravenous injection of substances to determine the effect of each substance on normal body variables, the change in serum Na+ when substance B is injected is insignificant. 

Which of the following helps to maintain the fluidity of the blood?

biology simple nutrients into cells blood and its components components of blood composition of blood

  1. Plasma

  2. RBC

  3. WBC

  4. None of the above

Show answer
Correct Option: A
Explanation:

One half of blood is composed of red blood cells, white blood cells and platelets which are considered as solid part of blood and another half is composed of water, salts and proteins which is the fluid part of blood. The fluid part of blood is known as plasma. As the plasma consists of water it helps to maintain the fluidity of the blood.

So, the correct answer is 'Plasma'.

Raising of pH of blood shall result in

biology simple nutrients into cells blood and its components components of blood composition of blood

  1. Inhibition of carbonic anhydrase

  2. Production of carbon monoxide and causing carbon monoxide poisoning

  3. Non-release of carbon dioxide from carbonic acid and carbonates

  4. Non-dissociation of oxygen from oxyhaemoglobin.

Show answer
Correct Option: D
Explanation:
A decrease in pH (increase in $H^+$ ion concentration) various amino acid residues, such as Histidine 146 exist predominantly in their protonated form allowing them to form ion pairs that stabilize deoxyhemoglobin thereby having a lower affinity for oxygen. So with increased acidity, the hemoglobin binds less $O _2$.This is known as the Bohr effect. The binding affinity of hemoglobin to O2 is greatest under a relatively high pH and oxygen does not disassociate with hemoglobin under increased pH conditions.
So the correct answer is 'Non-dissociation of oxygen from oxyhemoglobin.'

The term synergistic action of hormones refers to

biology control and co-ordination in plants and animals movements in plants coordination in plants tropic and nastic movements in plants

  1. When two hormones act together but bring about opposite effects.

  2. When two hormones act together and contribute to the same function.

  3. When one hormone affects more than one

  4. When many hormones bring about any one function.

Show answer
Correct Option: B
Explanation:
Growth, differentiation and development processes of plants are found to be regulated by two or more phytohormones acting synergistically or antagonistically, e.g. cell division is promoted by both auxins and cytokinins acting synergistically. Cell growth is controlled by auxins, gibberellins, and cytokinins. Morphogenesis is an interplay of auxins and cytokinins, where both must be present in some minimum concentration.
So the correct answer is 'When two hormones act together and contribute to the same function.'.

Movement caused by injury is

biology control and co-ordination in plants and animals movements in plants coordination in plants tropic and nastic movements in plants

  1. Traumotropism

  2. Rheotropism

  3. Traumonasty

  4. Rheonasty

Show answer
Correct Option: A
Explanation:

The movement of plant part as a result of injury is called as traumatropism. It this, due to injury or wound, plant changes its orientation. Growth of plant part in response to the current of water is called as rheotropism. Folding of leaves in response to injury is called as traumonasty. 

Thus, the correct answer is option A.

The sun loving plants are referred to as

biology life processes: control and coordination movements in plants coordination in plants tropic and nastic movements in plants

  1. Halophytes

  2. Heliophytes

  3. Heterotrophs

  4. Sciophytes

Show answer
Correct Option: B
Explanation:

Halophytes are salt lovers and grow in marshy areas and other places with high salt concentrations. 

Heterotrophs are the organism that cannot manufacture their own food and depend on other living or dead organisms for their nutrition, example fungi and animals. 
Plants are autotrophs and can manufacture their own food through the process of photosynthesis. 
Plants growing in shade are called sciophytes or shade lovers. Plants growing in sun are called as heliophytes or sun lovers. Sciophytes have comparatively darker leaves and have higher amount of chlorophyll to capture scarce light. Heliophytes have lesser amount of chlorophyll as compared to sciophytes as they easily get enough light for the purpose of photosynthesis.

Bending of growing shoot towards sunlight is called

biology life processes: control and coordination movements in plants coordination in plants tropic and nastic movements in plants

  1. Heliotropism

  2. Hydrotropism

  3. Photonasty

  4. None of these

Show answer
Correct Option: A
Explanation:

Heliotropism- The growth of plants or plants parts esp flowers in response to the stimulus or sunlight, so that they turn to face the sun. It enhances the photosynthesis process and increases growth rates.

So, the correct answer is 'Heliotropism'.

The core component of central nervous system is 

biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

  1. Blood

  2. Neurons

  3. Ganglia

  4. Both A and B

Show answer
Correct Option: B
Explanation:
  • Neurons are the basic units of the nervous system. Every neuron is made of a cell body (also called a soma), dendrites and an axon. Dendrites and axons are nerve fibres.
  • The central nervous system consists of the brain and the spinal cord
  • The human brain contains around 100 billion neurons.
  • Hence the core component of the central nervous system is  Neuron.
  • So, the correct answer is 'Neurons'.