Answer: 1 and 3
Explanation:
Sources of water: plants need water for certain cellular processes especially PHOTOSYNTHESIS. Otherwise, it Will not produce food and then die. So, first land plants need Sources of water.
Dessication: refers to drying up of plants tissues DUE to LACK of water. First land plant are most likely to suffer dessication.
Other options are NOT specific to first land plants
 
        
             
        
        
        
Answer:
Fever c) is regulated by chemicals that reset the body's thermostat to a higher setting
Explanation:
Fever is a high body temperature and is one of the ways our immune system attempts to combat an infection. It is also referred to as pyrexia and it could be more than between 37.2 and 38.3 °C (99.0 and 100.9 °F) in humans, there is not a single agreed-upon upper limit. <em>Temperature is regulated in the hypothalamus.</em> Fever helps your immune system fight infections by speeding up the functioning of cells and it makes it harder for bacteria and viruses to thrive in the body.
 
        
             
        
        
        
The two upper chambers are the atria or auricles. They are the left and right atriums
        
             
        
        
        
Answer:
B) ecological succession
Explanation:
The analogy given in this question describes ECOLOGICAL SUCCESSION, which is the series of changes that an ecosystem undergoes over a period of time. Ecological succession is of two types viz: Primary succession and Secondary succession. 
Primary succession involves the series of changes that occurs on a new habitat that has never been previously colonized. This is the case of the colonization of bare rocks with no plant life by LICHENS. The action of the lichen, which involves secretion of acids that disintegrates the rocks into soil, paves way for the colonization of that area by new species. 
Lichens, via the role they play in primary succession by helping alter a barren area into a fertile one that accommodates other organisms, makes them be regarded as PIONEERS of primary succession.
 
        
             
        
        
        
What is different with retroviruses in reproduction is that they do not kill their hosts at first because they can still insert their own genome. This process is what is known the reverse transcription. This is done by different proteins.