Answer:
A. Lancelet
B. All chordates
Explanation:
A. Dorsal nerve chord is the only <u>unique feature</u> among all members of <u>phylum chordata</u> (mainly found in subphylum Vertebrata). In the given list, only lacelet is the Chordate whereas <u>snail belongs to phylum Mollusca</u>, <u>grasshopper belongs to Arthropda</u>, and <u>jellyfish belongs to Cnidaria</u>. Dorsal nerve cord runs along the length of organism's body.
B. <u>Gill slits</u> are <u>opening structures</u> to gills through which water passes from pharynx/throat to exterior. Their main purpose is to help filter the food particles available in surrounding water. Although they are typical for amphibians and fishes, chordates also possess gill slits at embryonic stages.
Answer:
4 possible combinations of gametes
Explanation:
The animal is considered an heterozygotic dihybrid because it involves two genes that have different alleles for both genes. The dihybrid animal undergoes meiosis to produce gametes. According to Mendel in his laws of segregation and independent assortment, the alleles of the two genes separate into gametes independently of one another to produce 4 types of gametes.
Number of possible combinations of gametes formed by an heterozygote can be determined by using 2^n, where n is the number of characters. Number of characters or genes involved in this case is 2, Hence, 2^2 = 4 gametes.
The allelic combination in the four gametes are: AB, Ab, aB, ab.
Answer:
First, the zygote becomes a solid ball of cells. Then it becomes a hollow ball of cells called a blastocyst. Inside the uterus, the blastocyst implants in the wall of the uterus, where it develops into an embryo attached to a placenta and surrounded by fluid-filled membranes.
<span>A form of massage that's a popular choice for dogs and horses is tTouch massage.</span> It is therapeutic massage for dogs and horses and promotes their health. It is done with fingers and hands all over the body of the dog. The movements are circular. The goal of the massage is to activate the function of the cells and awaken cellular intelligence of the dog.