Homologous structures are features that are similar in structure but appear in different organisms and have different functions, and are also evidence of common Therefor, the striped coat of the zebra and the tiger are homologous features, so D. is the correct answer.
The question is incomplete. The complete question is:
Question: Innate immunity:
a) is based on recognition of antigens that are specific to a pathogen.
b) is the first and most general, mechanism of protection against pathogens
c) is found only in vertebrates
d) depends on an infected animal's previous exposure to a pathogen
Answer:
b) is the first and most general, mechanism of protection against pathogens
Explanation:
Innate immunity is the nonspecific immune response that provides immediate and the most general protection against all types of pathogens, parasites, toxins and cancer cells. Innate immune responses serve to prevent the pathogens from entering the body. The components of innate immunity also rapidly destroy those pathogens that have entered the body.
Some of the components of innate immunity are the first line of defense such as the physical and chemical barriers of the skin and mucous membranes. The components of the second line of defense such as natural killer cells, phagocytes and inflammatory response are also involved in innate immune responses.
For example, cuticle or skin serves as a physical barrier to pathogens that come in contact with an animal’s body. Phagocytosis kills the bacteria that invade the body.
Answer:
Rr and rr
Explanation:
The genotypes of the parents would be heterozygous red (Rr) and true-breeding white (rr).
<em>Since the allele for the red flower color (R) is dominant over that of the white flower color (r), for a cross to produce both red and white flower color plants, the red parent must be heterozygous (Rr) and the white parent true-breeding (rr). </em>
Rr x rr
Rr Rr rr rr
Rr = red
rr = white
If the red parents is true-breeding
RR x rr
Rr Rr Rr Rr
All their offspring would be red without any white flower color.
Hence, the genotypes of the parent are Rr and rr.
Easy
how many times will it double
80/20=4
double 4 times
2*2*2*2=16
16 of them after 80 mins
