Answer:
The water bottle sign or configuration refers to the shape of the cardiac silhouette on erect frontal chest x-rays in patients who have a very large pericardial effusion. Typically the effusion has accumulated over many weeks to months (e.g. in patients with malignancy) and the pericardium has gradually stretched.
 
        
             
        
        
        
The extra X chromosome is received from mother.
<h3><u>Explanation</u>:</h3>
Klinefelter's syndrome is the condition of chromosomal aberration where the person has an extra X chromosome. This means the genotype of the person is 44+XXY and the total chromosome number is 47. This condition is achieved due to inappropriate meiotic division and one of the sperm or ovum has the an extra X chromosome.
Here both the parents are normal in terms of colour vision. So the father cannot have the gene of colour blindness because if it was present, then father would have been colour blind because he has only one X chromosome per cell. So its present in mother who is heterozygous in terms of colour blind gene. So the extra X chromosome also came from her which made the presence of two defective X chromosomes in the offspring and made it colour blind. 
 
        
             
        
        
        
<h2>Galapagos Finch </h2>
Explanation:
Darwin's finches are a classical example of an adaptive radiation
- Darwin's finches common ancestor arrived on the Galapagos about two million years ago,during the time that has passed the Darwin's finches have evolved into 15 recognized species differing in body size, beak shape, song and feeding behavior
- Changes in size and form of the beak have enabled different species to utilize different food resources such us insects, seeds, nectar from cactus flowers all driven by Darwinian selection
- From 1831 to 1836, Darwin was part of a survey expedition carried out by the ship HMS Beagle, which included stops in South America, Australia, and the southern tip of Africa
- At each of the stop, Darwin had the opportunity to study the local plants and animals
- Darwin found that nearby islands in the Galapagos had similar but nonidentical species of finches living on them,he noted that each finch species was well-suited for its environment and role
- For example species that ate large seeds tended to have large, tough beaks, while those that ate insects had thin, sharp beaks
- According to Darwin's idea, this pattern would make sense if the Galapagos Islands had long ago been populated by birds from the neighboring mainland
- On each island, the finches might have gradually adapted to local conditions (over many generations and long periods of time)
- This process could have led to the formation of one or more distinct species on each island
- Darwin developed and refined a set of ideas that could explain the patterns he had observed during his voyage
- In his book, On the Origin of Species, Darwin outlined his two key ideas: evolution and natural selection
- Natural selection which also known as “survival of the fittest,” is the more prolific reproduction of individuals with favorable traits that survive environmental change because of those traits; this leads to evolutionary change
 
        
        
        
Answer:
The correct answer is option 3. a nucleus.
Explanation:
The first genetic material present in the early organisms were RNA which was present in the microscopic organisms back then 3.5 billion years ago which means it is normal to have RNA in such microfossils chemical analysis.
Since, the nucleus was not present in early life forms of prokaryotes like bacteria. so, it is unusual to find nucleus in the fossils of stromatolite rocks.
Thus, option III is the correct answer.