Question

The term for an organism’s visible, evident, or detectable physical traits is _______________.
       a. genotype
       b. phenotype
       c. code
       d. recessive allele

Which is the following statements regarding the theory of evolution is true:
       a. Newer traits are better than older, primitive traits
       b. Natural selection always works
       c. Natural selection always produces perfect structures
       d. All of the above
       e. None of the above

Which of the following represents a dominant heterozygous pair?
       a. rr
       b. RR
       c. Rr
       d. none of the above

An individual who is homozygous for a gene has __________.
       a. different alleles for the gene
       b. no alleles for that gene
       c. two of the same alleles for that gene
       d. only one locus for that particular gene

According to the theory of natural selection:
       a. Physical variation within a species is critical.
       b. Populations always increase faster than the resources on which they depend.
       c. New species emerge because the organisms with advantageous variations become a larger percent of the population.
       d. a and b
       e. a, b, and c

A ___________________ is a set of hypotheses that have been tested repeatedly and that have not been rejected.
       a. Fact
       b. Observation
       c. Hypothesis
       d. Theory

True or false: It is likely that every individual carries a mutation in their body.
True

False

__________ anthropology is the study of humans as biological organisms, considered in an evolutionary framework.
       a. Astronomical
       b. Physical
       c. Molecular
       d. Osteological

In proper pairings, DNA base combinations are always __________.
       a. A-T or C-G
       b. A-G or C-T
       c. G-T or A-C
       d. A-D or C-D

True or false: All of the DNA in our body is part of a gene?
True

False

Regulatory genes, which act like “lightswitches” in the body, are important because they:

       
always work at night.

       
help explain how large physical differences can exist between species that have very similar genes.

       
always lead to the most important mutations in the body.

       
help determine which species will dominate other species in the survival of the fittest.

In an evolutionary sense, a “bottleneck” occurs when:

       
a. Genes are spliced and created in a laboratory tube.

       
b. Too many species exist.

       
c. A sequence of genetic code cannot attach to a ribosome.

       
d. A random factor or chance changes or reduces the gene pool of a particular species.

Answer 1

1. The term for an organism’s visible, evident, or detectable physical traits is the phenotype.

The phenotype of an organism refers to the physical appearance of an organism.

Other options are incorrect because the genotype of an organism refers to the genetic composition of an organism. Recessive alleles are those alleles that are only expressed physically if they are homozygous. If they are paired alongside the dominant allele, their physical expression gets suppressed by the dominant allele.

2. All of the above

1. Newer traits are better than older, primitive traits (Newer traits are better than older traits because the environment's dynamics constantly change. So, in order to survive and adapt to this constantly changing environment, an individual must develop new traits.)

Natural selection always works. (Nature always favors the organism that is able to adapt to its ever-changing environment.)

Natural selection always produces perfect structures. (Natural selection produces perfect structures that benefit the organism the most in that particular environmental condition.)

3. Rr represents a dominant heterozygous pair.

R is the dominant allele whereas r is the recessive allele. Only the dominant allele R will be expressed in the phenotype of the organism.

Other options are incorrect as rr represents recessive homozygous pair and RR represents dominant homozygous pair.

4. An individual who is homozygous for a gene has two of the same alleles for that gene.

Example - rr and RE

Other options are incorrect

​​​​​​An individual who is heterozygous has different alleles for the gene. Example - Rr

No alleles for that gene. (All genes have at least two alleles)

Only one locus for that particular gene. (Each gene has one specific locus.)

5. a, b and c

1. Physical variation within a species is critical. (Natural selection will only take place if there is physical variation within a species.)

Populations always increase faster than the resources on which they depend. (The resources on which organisms are dependent on are limited. Hence, they search for new places and need to adapt to the environmental conditions of that place. This is how natural selection takes place.)

New species emerge because the organisms with advantageous variations become a larger percent of the population. (When the organisms develop new traits and get physically distinct from their earlier species, a new species is formed. As a result, the population of that species increases.)