Experimental Scenario Donna has observed that her father can control the speed of their grandfather clock by adjusting the

height of the weight on the end of the pendulum. Donna thinks that the pendulum will move faster

when the weight is lowered, and wants to test her idea. Donna gets a stopwatch and measures the

time it takes for the pendulum to swing twenty times when the weight is moved to its lowest position.

Donna begins to move the pendulum up by 1 cm and continues to measure the time for twenty swings

of the pendulum. Donna records her data

SCI 1.4 Investigation Plan

1) Provide a brief description of the methods that are being used to run the experiment

Reduce the mass and measure the speed of pendulum.

Explanation:

First measure the swings of the pendulum at its original weight. After that some weight is removed from the pendulum and again measure the number of swing of pendulum at specific time period. We have to reduce mass of pendulum and then measure the number of swings. In this way, this experiment moves forward and we can find out the impact of mass on the speed of pendulum.

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.