Tuesday daily questions and notes

Tuesday February 19th

A mosquito has 16 chromosomes in each somatic cell, how many chromosomes would be found in a mosquito’s gametes?
8 - Recall that gametes are HAPLOID cells and Somatic cells (normal body cells) are DIPLOID.  Haploid cells contain only ONE set of chromosomes while Diploid cells contain two sets (one from each parent).  If you are given the number of diploid chromosomes, you would divide that by 2 in order to determine the number of chromosomes in an organisms gametes.
The next question uses the same logic only in reverse. A frog’s haploid cells contain 13 chromosomes, how many chromosomes would be found in its somatic cells?
26

Which of the following explains why asexually reproducing organisms are more likely to go extinct when their environment changes?

1.  They reproduce without DNA

2.  They only reproduce in small numbers

3.  They lack a variety of genetic combinations.
 Remember, in asexuallly reproducing organisms all the offspring are genetically identical to the parent.  Because of this lack of variation if an environmental change wipes out one, it will wipe them ALL out!!

4.  They are easier for predators to capture

Which feature is common to all prokaryotic and eukaryotic organisms?

1.  Endoplasmic reticulum that stores fat reserves

2.  Ribosomes that produce complex carbohydrates (This was ALMOST correct, prokaryotic and eukaryotic cells both have Ribosomes. What made this answer incorrect was that ribosomes do not produce complex carbohydrates, they produce proteins.)

3.  Nucleic acids that code for genetic characteristics

4.  Mitochondria that are sites for cellular respiration

We continued through notes today -this time discussing the term "alleles" in a bit more detail before we move on into how those alleles get segregated during meiosis.

Here were the slides most classes made it through. (you can also check edline for the entire slide show)