Punnett squares: question 5 tay-sachs disease is caused by a recessive lethal allele, meaning that individuals that are homozygous recessive (tt) will have the disease and die before they are able to have offspring. two parents that are heterozygous (t) carriers for tay-sachs want to have children. what are the chances that their children will get tay-sachs disease?

Alaska and northern canada have a diet rich in vitamin d and their skin color is darker than predicted on the basis of iv intensity at their latitude. explain the observation:

Can you identify which of the following groups of organisms are, or are not, populations? a. the american bison (bison bison) and grey wolves (canis lupus) currently living in yellowstone national parkb. all of the rainbow trout (oncorhynchus mykiss that) that have ever lived in lake eriec. the group of american bison (bison bison) currently living in yellowstone national parkd. a group of calliope hummingbirds (selasphorus calliope) and a group of rufous hummingbirds (selasphorus rufus) living in the same new hampshire woodse. the northern cardinals (cardinalis cardinalis) living on opposite shores of lake champlain f. all of the whales currently living in the atlantic ocean off cape cod, massachusetts

Why does meiosis produce cells with half the chromosomes? o a. most of the chromosomes are not necessary to keep an organism alive. b. a gamete needs only half the number of chromosomes because two gametes join together. o c. it makes the gametes easier to move around in the organism. o d. it is faster to produce gametes with fewer chromosomes.