Fertilization (the fusing of one sperm and an ovum) results in a(n) _____.

Answer Explanation

The cell cycle is an organized process divided into two phases: interphase and the M (mitotic) phase. During interphase, the cell grows and copies its DNA. After the cell reaches the M phase, division of the two new cells can occur. The G1, S, and G2 phases make up interphase.

• G1: The first gap phase, during which the cell prepares to copy its DNA
• S: The synthesis phase, during which DNA is copied
• G2 : The second gap phase, during which the cell prepares for cell division

It may appear that little is happening in the cell during the gap phases. Most of the activity occurs at the level of enzymes and macromolecules. The cell produces things like nucleotides for synthesizing new DNA strands, enzymes for copying the DNA, and tubulin proteins for building the mitotic spindle. During the S phase, the DNA in the cell doubles, but few other signs are obvious under the microscope. All the dramatic events that can be seen under a microscope occur during the M phase: the chromosomes move, and the cell splits into two new cells with identical nuclei.

Answer Explanation

Kidneys makes urine is incorrect. Kidneys do not make urine. They help regulate water balance, regulate levels of electrolytes such as sodium and potassium, and eliminate metabolic wastes. Urine is a byproduct of these functions.

As a person ages, kidney tissue and filtration capacity increase is incorrect. As a person ages, the kidneys and bladder change. This can affect functions such as bladder control and how well the kidneys filter blood. Kidney changes range from a decrease in kidney tissue to decreased filtration capacity.

Kidneys help regulate water balance is correct. Kidneys help regulate water balance, regulate levels of electrolytes such as sodium and potassium, and eliminate metabolic wastes. Urine is a byproduct of these functions.

Regulates levels of electrolytes such as sodium and potassium is correct. There must be a continual balance of water and salt in the blood. The urinary system, specifically the kidneys, help maintain this balance. It also balances levels of metabolites or electrolytes such as sodium, potassium, and calcium.

Eliminates metabolic wastes is correct. Urea, creatinine, uric acid, and ammonium are the primary types of nitrogenous wastes excreted from the body. The urinary system also detects and excretes excess water from the blood and out of the body.

Answer Explanation

One step of the scientific method is to analyze information or data collected from the experiment to conclude whether the hypothesis is supported.

Recall that these make up the scientific method, described below:

• Problem: The question created because of an observation. Example: Does the size of a plastic object affect how fast it naturally degrades in a lake?
• Research: Reliable information available about what is observed. Example: Learn how plastics are made and understand the properties of a lake.
• Hypothesis: A predicted solution to the question or problem. Example: If the plastic material is small, then it will degrade faster than a large particle.
• Experiment: A series of tests used to evaluate the hypothesis. Experiments consist of an independent variable that the researcher modifies and a dependent variable that changes due to the independent variable. They also include a control group used as a standard to make comparisons. 
  • Example: Collect plastic particles both onshore and offshore of the lake over time. Determine the size of the particles and describe the lake conditions during this time period.
• Observe: Analyze data collected during an experiment to observe patterns. 
  • Example: Analyze the differences between the numbers of particles collected in terms of size.
• Conclusion: State whether the hypothesis is rejected or accepted and summarize all results.
• Communicate: Report findings so others can replicate and verify the results.