Ascientist discovered a new antibiotic and wanted to know if it would be effective against group a streptococcus bacteria. he designed a test experiment in a lab with ten different cultures of the bacteria. he introduced the antibiotic into five of the cultures, leaving the other five to grow without it. he recorded observations every three hours for a week.

what is the independent variable in this experiment?
a.
the presence of the new antibiotic
b.
the presence of the streptococcus bacteria
c.
the total number of bacteria cultures
d.
the reaction of the bacteria to the antibiotic

As , plants meet their needs for making food from air, soil, water, and the sun's energy in a process called there are plants called grow high in trees without here are words to put in the blanks. 1.) producers 2.) consumers 3.) chloroplasts 4.) epiphytes

The term used to describe a disease-causing microorganism isa. virus. b. infection. c. pathogen. d. microbe. e. bacterium.

The table presents the average day and night temperatures in five cities. it also reveals whether a city receives substantial rainfall (wet climate) or little rainfall (dry climate). which city’s rocks are likeliest to experience frost wedging, and why? a) city a because the consistently subzero temperature would prevent water from melting b) city b because it is a wet region and the temperature fluctuates around the freezing point c) city c because it receives plenty of rain fall and the weather is moderately cool d) city d because the hot and dry weather would cause rocks to absorb water