Answer:
recessive
Explanation:
A lethal allele is a gene variant associated with a mutation in an essential gene, which has the potential to cause the death of an individual. In general, lethal genes are recessive because these alleles do not cause death in heterozygous individuals, which have one copy of the normal allele and one copy of the allele for the lethal disease/disorder. In recessive lethal diseases, heterozygous individuals are carriers of the recessive lethal allele and can eventually pass the 'defective' allele on to offspring even though they are unaffected; whereas dominant lethal diseases are caused by dominant lethal alleles, which only need to be present in one copy to be fatal. In consequence, the frequency of recessive lethal alleles is generally higher than dominant lethal alleles because they can be masked in carrier individuals. Some examples of human diseases caused by recessive lethal alleles include, among others, Tay-Sachs disease, sickle-cell anemia, and cystic fibrosis.
It penetrates the skin and can cause mutations.
Answer:
Earliest- gametophyte dominance, sporophyte dependence
Middle- sporophyte dominance, gametophyte independence
Recent- sporophyte dominance, gametophyte dependence
Explanation:
The life cycle of plant alternates between the two phases: the haploid gametophyte which produces gametes and the diploid sporophyte which produces spores. The evolution of land plants shows how these are dependent on each other in terms of the requirement of nutrition.
In bryophytes, the gametophyte is the dominant phase on which the sporophyte depended. Later in pteridophytes, the sporophyte became dominant which is present in the later evolved groups namely the gymnosperms and the angiosperms. The gametophyte was independent on the sporophyte but in angiosperms and gymnosperms, it is dependent.
Answer:
rashes is caused by heat while skin infection is caused by bacteria and infection
Answer:
Xylem is one of the two types of transport tissue in vascular plants, phloem being the other. The basic function of xylem is to transport water from roots to stems and leaves, but it also transports nutrients.
Explanation:
