In terms of organisms, photosynthesis occurs in autotrophes that contain the green pigment chlorophyll. This would include the entire plant kingdom, half of the Protista (the algae), & half the Moneran Kingdom (the blue-green algae).
A standard twin mattress is 39 by 75 inches. A king is 76 by 80 inches. This means that a headboard for a king bed is going to be about 76 inches or wider, plenty wide enough to go along the length of a twin bed. Headboards are often slightly wider than the bed for which they are made.
Description : Twin mattresses are also known as 'singles' and are the ideal choice for children bedrooms and for multi user guest rooms. Their narrow width fits most small rooms. A variation of the mattress is the Twin XL mattress which is 5 inches longer than the standard twin size but has the same width . They are commonly used in college dormitories and hostels to accommodate tall teens and are often used in bunk beds also. Dimensions : Standard twin : 39 (width) x 75 (length)