Which type of wave does not require a medium in which to travel?

Sound

Water

Light

Mechanical

The dose of an antigen that kills 50% of animals in a test group and is used to estimate the virulence of a pathogen is known as

If an individual carries only two alleles, is it possible for a single gene to have more than two alleles? no. if a gene had more than two alleles, it would be too variable to be identified as one gene.

Denise heard that little children pick food based upon color. She read many studies about food color and selection. She learned when foods are not the color people expect, it makes them think the flavor is different.

1, Explain the endosymbiotic theory of the origin of eukaryotic cells in your own words. 2, Compare at least two characteristics of mitochondria to prokaryotic cells and explain how this relates to the endosymbiotic theory. 3.

Which of the following modifications of a stem provides storage?

One Significant Figure Two Significant Figures Three Significant Figures Four Significant Figures 200 | 0.01 || 20 22||20. 1,230|| 8.88 || 136 155.6 || 1,245 8.880 One significant figure 200,0.01,20 Two significan figures 22, 20.

Felipe made a toy boat out of clay, but it kept sinking in water. He changed the boat's design by making it slightly wider than before. Why did Felipe's newly designed boat float on water? (a) He decreased the density by increasing the volume.

Why do cells need to divide? A. contain to many chromosomes. B. Cells need to get rid of waste products. C. cells cannot live unless they divide often. D. Cell division is how organisms grow

Which of the following is not part of the carbon cycle? -Photosynthesis in plants -Respiration in plants -Evaporation of water from the oceans -Decay of plants

What would happen if a keystone species is removed from an ecosystem