Making Connections

In the lab activity Making Connections, an experiment was designed to test the effect of exercise on the ability to squeeze a clothespin. The number of times the clothespin was squeezed served as the

• independent variable

• dependent variable

• hypothesis

• control

Students were asked to design a lab that investigated the relationship between exercise and heart rate. Heart rate was determined by recording the pulse rate in beats per minute. The students hypothesized that increased exercise results in an increased heart rate. The class results for the experiment are shown in the graph. Students in a different science class carried out the same experiment. The data they obtained did not support the hypothesis that increased exercise results in increased heart rate. The most scientifically sound way to deal with this situation is to

• write a new hypothesis

• read about pulse rate in a biology textbook

• have the students in both classes vote to decide which hypothesis is correct

• ask students in a third class to do the experiment and see if their results support the hypothesis

An experiment was conducted to determine the effect of activity on pulse rate. Data were collected and recorded in the table shown.

Which activity most likely corresponds to the pulse rate of the person while sleeping?

• 1

• 2

• 3

• 4

In the lab activity 'Making Connections', an experiment was designed to test the effect of exercise on the ability to squeeze a clothespin. The number of times the clothespin was squeezed served as the

• independent variable

• dependent variable

• hypothesis

• control

Which of the following best describes the role of a control group in an experiment?

• To provide a standard for comparison

• To introduce a new variable

• To ensure the experiment is biased

• To change the outcome of the experiment

In a scientific experiment, what is the purpose of repeating trials?

• To increase the sample size

• To introduce new variables

• To ensure consistent results

• To change the hypothesis

What is the primary function of the nervous system in making connections within the body?

• To transport nutrients

• To transmit signals

• To produce hormones

• To digest food

Which part of the neuron is responsible for receiving signals from other neurons?

• Axon

• Dendrite

• Cell body

• Synapse

Tags

NGSS.MS-LS1-2

In the context of making connections, what is synaptic plasticity?

• The ability of synapses to change strength

• The rigidity of synapses

• The number of synapses in the brain

• The speed of signal transmission

How does exercise influence the connections between neurons in the brain?

• It decreases synaptic strength

• It increases synaptic strength

• It has no effect

• It destroys synapses