Why must the number of chromosomes in the sperm and egg be half the number of chromosomes in the other cells of an organism?

Which of the following statements about DNA is true? *DNA is single-stranded * DNA contains uracil *DNA has the sugar ribose * DNA contains thymine

My answer is B Species adapt over time through structural and behavioral adaptations. Which example describes a behavioral adaptation of a lion? A. strong legs for running B. protective over young cubs C. sharp claws for capturing prey D.

An organism that is killed and eaten by another is what

What is upwelling? A. The mixing of two biomes B. The productivity of an ecosystem C. When infertile species reproduce O D. Water moving up from the benthie zone

What is responsible for respiration in frogs? lungs gills tracheae skin

Describe how viruses and bacteria can be used as biological weapons. What are some of the potential threats and potential benefits? Do you agree with the use of viruses and bacteria as biological weapons? Why or why not?

Because humans are diploid organisms, their body celle contain

How many years do stars live for?

What does not move accross axons? a) neither electrons nor ions b) electrons c) ions and electrons d) ions

Engaging in regular physical activity and reducing sedentary activities can: A. Promote health B. Enhance psychological well-being C. Promote a healthy body weight D. All of the above