Answer: D
Explanation:
A change in the amount of polar ice will alter how ocean currents move
 
        
             
        
        
        
It has been estimated that ‘slash and burn’ agriculture is
used by up to 500 million people worldwide. The term describes the practice of
cutting and/or burning of natural vegetation for conversion into agricultural
fields. Besides the disastrous implications for forest ecosystems, the practice
can impact the atmosphere in two main ways if burning is implemented. Firstly
by causing air pollution from the smoke, and secondly by increasing carbon
dioxide in the atmosphere, which is a greenhouse gas and a driver of climate
change. Living trees also remove carbon dioxide from the atmosphere during
photosynthesis, and the process of ‘slash and burn’ effectively removes their
carbon capturing contributions to ameliorating climate change.
 
        
                    
             
        
        
        
Tiktaalik is a transitional fossil which shows how fish evolved into amphibians and reptiles. So the correct option is B. 
What is Tiktaalik? 
Tiktaalik is a direct ancestor of tetrapods or four-legged animals. It is an extinct fish-like animal and it lived on earth 380-385 million years ago (Devonian period). 
The word Tiktaalik is derived from the <em>Inuktitut</em> language which loosely translates to large freshwater fish. This animal had characteristics of both fish and tetrapod and is therefore called the link between these two kinds of animals. 
The characters resembling fish are gills and scales and the characters resembling tetrapods are rib bones, movable neck and lungs. There are characters that are a mix of both tetrapods and fish. These are bones and joints in limbs but fish-like fins instead of feet or hands. 
Read more about Tiktaalik, here
brainly.com/question/10138798
#SPJ1
 
        
             
        
        
        
germ cells
it occours in the germ cells 
 
        
                    
             
        
        
        
Answer:
1. Double helix is the description of the structure of a DNA molecule. A DNA molecule consists of two strands that wind around each other like a twisted ladder. Each strand has a backbone made of alternating groups of sugar (deoxyribose) and phosphate groups.
2. The DNA double helix. The two sides are the sugar-phosphate backbones, composed of alternating phosphate groups and deoxyribose sugars. The nitrogenous bases face the center of the double helix.
3. A nucleotide is an organic molecule that is the building block of DNA and RNA. ... A nucleotide is made up of three parts: a phosphate group, a 5-carbon sugar, and a nitrogenous base. The four nitrogenous bases in DNA are adenine, cytosine, guanine, and thymine.
4. A nucleotide is made up of three parts: a phosphate group, a 5-carbon sugar, and a nitrogenous base. The four nitrogenous bases in DNA are adenine, cytosine, guanine, and thymine.
5. In genetics, the term junk DNA refers to regions of DNA that are non-coding. Some of this noncoding DNA is used to produce noncoding RNA components such as transfer RNA, regulatory RNA and ribosomal RNA 
Hopes this helps.