Biology, 20.08.2019 21:00 msdmdsm1186

What are two ways bacteria provide nutrients to humans?

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1. they break down cellulose that humans cannot digest
2. they break down lactose with lactic acid that humans cannot produce

Answer from: Quest

the correct answer is d

Answer from: Quest

the african cheetah.

this species has a relatively low level of genetic

variation because the population was reduced to a small size approxi-

mately 10,000 to 12,000 years ago.

chapter outline

24.1

genes in populations and the hardy-

weinberg equation

24.2

factors that change allele and genotype

frequencies in populations

24.3 sources of new genetic variation

population genetics

until now, we have primarily focused our attention on genes

within individuals and their related family members. in this

chapter and chapters 25 and 26 , we turn to the study of genes in

a population or species. the field of

population genetics

is con-

cerned with changes in genetic variation within a group of indi-

viduals over time. population geneticists want to know the extent

of genetic variation within populations, why it exists, and how it

changes over the course of many generations. the field of popu-

lation genetics emerged as a branch of genetics in the 1920s and

1930s. its mathematical foundations were developed by theoreti-

cians who extended the principles of gregor mendel and charles

darwin by deriving formulas to explain the occurrence of geno-

types within populations. these foundations can be largely attrib-

uted to three scientists: sir ronald fisher, sewall wright, and j. b. s.

haldane. as we will see, support for their mathematical theories

was provided by several researchers who analyzed the genetic com-

position of natural and experimental populations. more recently,

population geneticists have used techniques to probe genetic

variation at the molecular level. in addition, staggering advances

in computer technology have aided population geneticists in the

analysis of their genetic theories and data. in this chapter, we will

explore the genetic variation that occurs in populations and con-

sider the reasons why the genetic composition of populations may

change over the course of several generations

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