Question

scientific variables
identify the independent and dependent variable in each scenario.
scenario
one chicken is injected with a growth hormone while another chicken is not injected. both chickens are weighed after a year.
a bug repellent is sprayed on one arm the other arm is not sprayed. the number of bug bites is recorded after 2 hours.
javier sleeps 9 hours the night before his science exam. his twin sister has the same exam and sleeps 6 hours the night before the test. afterwards, they compare their scores.
group a exercises for a month. group b does not exercise. they measure the amount of weight they gained.
one math class studies for an assessment while the math class next door does not. the scores of the two classes are compared.
one plant is given sunlight every day. another plant is not given any sunlight. after 3 weeks, we measure how tall the plant is.
one plant is given sunlight for 12 hours a day. another plant is not given any sunlight. after 3 weeks, we compare how green each plant looks.

Explanation:

Step1: Recall variable - definition

Independent variable is the variable that is changed or controlled in an experiment. Dependent variable is the variable being tested and measured.

Step2: Analyze bug - repellent scenario

The presence or absence of bug - repellent is controlled. So, the independent variable is Bug - repellent. The number of bug bites is what is measured, so the dependent variable is Number of bug bites.

Step3: Analyze sleep - exam scenario

The amount of sleep is controlled. So, the independent variable is Hours of sleep. The exam scores are what is measured, so the dependent variable is Exam scores.

Step4: Analyze exercise - weight scenario

The exercise (exercise or no - exercise) is controlled. So, the independent variable is Exercise. The amount of weight gained is what is measured, so the dependent variable is Amount of weight gained.

Step5: Analyze study - score scenario

The study (studying or not studying) is controlled. So, the independent variable is Studying. The class scores are what is measured, so the dependent variable is Class scores.

Step6: Analyze plant - sunlight height scenario

The presence or absence of sunlight is controlled. So, the independent variable is Sunlight. The height of the plant is what is measured, so the dependent variable is Height of plant.

Step7: Analyze plant - sunlight greenness scenario

The presence or absence of sunlight is controlled. So, the independent variable is Sunlight. The greenness of the plant is what is measured, so the dependent variable is Greenness of plant.

Answer:

Scenario	Independent	Dependent
Sleep - exam	Hours of sleep	Exam scores
Exercise - weight	Exercise	Amount of weight gained
Study - score	Studying	Class scores
Plant - sunlight height	Sunlight	Height of plant
Plant - sunlight greenness	Sunlight	Greenness of plant