Which type of solution will bring about deplasmolysis?
A plasmolysed cell placed in a hypotonic solution undergoes deplasmolysis.
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What happens when a pressure greater than the atmospheric pressure is applied to pure water or a solution?
Applying pressure higher than atmospheric to pure water or a solution elevates its water potential. This heightened pressure induces an increase in the system’s overall water potential. The water potential, influenced by external pressure, rises beyond its baseline in response to the applied force. Essentially, elevated pressure results in an augmented water potential within the … Read more
What is osmotic pressure?
Osmotic pressure: Osmotic pressure is the pressure imbalance that halts the solvent’s net movement into a solution through a semipermeable membrane. Equilibrium occurs when the column’s hydrostatic pressure equals the osmotic pressure.
What is genetic variations? Explain the different factors responsible for genetic variations.
Genetic variation refers to the diversity in DNA sequences among individuals within a population, occurring in both germ cells (sperm and egg) and somatic cells (all other cells). Genetic variations are caused by following factors: I. Mutation: • Definition: Sudden, permanent heritable changes. • Types: Gene mutation (point mutation), chromosome structure mutation, chromosome number mutation. • Effect: Alters … Read more
What is isolation? Describe different type of reproductive isolation.
Isolation refers to the division of a species’ population into smaller units, where organisms in these subunits are hindered from interbreeding by barriers known as isolating mechanisms. Different type of reproductive isolation are as follows: I. Geographical Isolation: • Physical barriers like rivers, oceans, mountains, or glaciers divide the original population. • Organisms can’t cross these … Read more
Describe the Urey and Millers experiment.
Stanley L. Miller and Harold C. Urey’s Experimental Support for Oparin’s Chemical Evolution Theory: Apparatus and Procedure: Miller and Urey devised a spark-discharge apparatus, a glass chamber, to experimentally validate Oparin’s chemical evolution theory. The apparatus was sterilized, evacuated, and filled with methane, ammonia, and hydrogen gases in a 1:2:2 ratio. A tube introduced water … Read more
By talking industrial melanism as one example. Explain the concept of natural selection.
1. Industrial melanism, a prime example of natural selection studied by Kettlewell, involved two UK peppered moth varieties: Biston betularia and Biston carbonaria. 2. In pre-industrial Britain, Biston betularia outnumbered Biston carbonaria. B. Betularia was greyish-white, while B. carbonaria had a melanic form. 3. Nocturnal moths rested on tree trunks during the day. White-winged moths … Read more
What is adaptive radiation? Explain with suitable example.
1. Adaptive radiation, a pivotal process in evolution, entails the transformation of an original species into a diverse array of varieties. 2. A notable illustration of adaptive radiation is found in Darwin’s Finches. During Charles Darwin’s exploration of the Galapagos Islands, he observed a variety of small birds known as finches. 3. Darwin’s observations suggested … Read more
Would you consider wings of butterfly and bat as homologous or analogous and why?
The wings of a butterfly and a bat are analogous, meaning they share similar functions but do not have a common evolutionary origin. Examples of analogous structures include: 1. Butterfly wings and bird wings may appear similar, but they are not anatomically alike, despite serving similar functions. 2. The eyes of an octopus and mammals … Read more