A) If red hair were a recessive trait, it could be inherited in two ways: 1) from heterozygous parents who both carry the red hair allele (the chances of having a child with red hair would be 25%), or 2) from red haired parents who are both homozygous (100% chances of red haired offspring).
B) If red hair were a dominant trait, it could be inherited only if at least one of the parents had red hair. There's 3 variables: 1) If both parents were heterozygous, they would have a 75% chances of having red haired children; 2) if one parent were heterozygous and the other were homozygous dominant, all of their offspring would have red hair; and 3) all children would be red haired if both parent were homozygous, one dominant and the other recessive.
This exercise is an example of Mendelian inheritance which states that the genes inherited from parents are separated into gametes in equal frequency. Each parent "donate" an allele to their offspring; this allele could be physically expressed or not depending on it being dominant or recessive (this means: silent) and if the parents being homozygous or heterozygous. Heterozygous individuals have two different alleles (one dominant and one recessive), while homozygous can have either 2 dominant alleles or 2 recessive ones.
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Explanation:
The flatworms are acoelomate organisms that include many free-living and parasitic forms. Most of the flatworms are classified in the superphylum Lophotrochozoa, which also includes the mollusks and annelids. The Platyhelminthes consist of two lineages: the Catenulida and the Rhabditophora. The Catenulida, or “chain worms” is a small clade of just over 100 species. These worms typically reproduce asexually by budding. However, the offspring do not fully detach from the parents and therefore resemble a chain in appearance. All of the remaining flatworms discussed here are part of the Rhabditophora. Many flatworms are parasitic, including important parasites of humans. Flatworms have three embryonic tissue layers that give rise to surfaces that cover tissues (from ectoderm), internal tissues (from mesoderm), and line the digestive system (from endoderm). The epidermal tissue is a single layer cells or a layer of fused cells (syncytium) that covers a layer of circular muscle above a layer of longitudinal muscle. The mesodermal tissues include mesenchymal cells that contain collagen and support secretory cells that secrete mucus and other materials at the surface. The flatworms are acoelomates, so their bodies are solid between the outer surface and the cavity of the digestive system.
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The respiratory centers that control your rate of breathing are in the brainstem or medulla. The nerve cells that live within these centers automatically send signals to the diaphragm and intercostal muscles to contract and relax at regular intervals.
(hope it helped)
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E
Explanation:
Wind blowing across the body surface increases transpiration of the skin. The winds reduce the local air pressure above the skin allowing the sweat to evaporate faster. As the sweat evaporates, it carries with it heat from the body. This cools the skin much faster than on a non-windy day. This is why a breeze feels so cool on the human skin on a hot day.
