He is incorrect because a catalyst is a substance that speeds up a chemical reaction so if there is no reaction to begin with a catalyst will not due anything.
        
             
        
        
        
The answer is cell membrane
        
             
        
        
        
Answer:
"My nutritionist measures energy content of food by using a bomb calorimeter."
Explanation
Animals humans included eat food in order to get chemical energy through cellular respiration either aerobically or anaerobically.
Therefore, food energy is the amount of chemical energy that can be derived from food.
Food energy can be measured using a bomb calorimeter and the unit of measurement is calories.
So when the client made the statement and mentioned energy content in food being measured by a calorimeter, it shows the client had an understanding on how energy in food is measured. 
 
        
             
        
        
        
A single cell RNA seq analysis identifies 25 population of epidermal cells . 
<h3>What is single cell transcriptomics used for?</h3>
Single cell transcriptomics are being used to create reference maps of healthy human tissues, organs and systems at single cell resolution. 
An essential model system for studying stem cells and tissue regeneration is the mouse epidermis with its hair follicles. To demonstrate how the cellular heterogeneity of the murine telogen epidermis is controlled at the transcriptional level, we used single-cell RNA-sequencing in this study. 25 different populations of interfollicular and follicular epidermal cells were identified by impartial clustering of 1,422 single-cell transcriptomes. With previously unheard-of resolution, our data allowed for the reconstruction of gene expression patterns during epidermal development and along the proximal-distal axis of the hair follicle. 
To Learn more about Transcriptomics refer 
brainly.com/question/14783864?referrer=searchResults
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