Answer:
D two organisms depend on each other for survival.
Explanation:
Symbiotic relationship is a type of relationship between two organisms in which the both of them gain something positive from each other. A good example is the relationship between the cattle and egret. The egret helps in grooming the cattle and the cattle in return provides food for the egret.
In a symbiotic relationship, two organisms depend on each other for survival and is the right choice in the above question.
Answer
Gametes that fertilize an ovum are called the sperms
Explanation
The reproductive cells of an organism are called the gametes or sex cells. Female sex cells are the ova/egg where as male sex cells are the sperms. The sperms are stored in the scrotum after their production in the male testes where as the eggs for females mature in female ovaries. During fertilization, sex cells meet in the Fallopian tube.
The answer to your question would be (<span>barter)</span>
Explanation:
The genes that determine color and pattern are linked.
- Solid pattern allele (L) is dominant over lined pattern (l)
- Blue color allele (B) is dominant over aqua color (b)
<h3><u>Initial cross</u></h3>
Homozygous lined aqua beetle has the genotype <em>lb/lb</em>
It can produce only 1 type of gamete: <em>lb</em>
X
Homozygous solid blue beetle has the genotype<em> </em><em>LB/LB</em>
It can produce only 1 type of gamete:<em> </em><em>LB</em>
The F1 is formed by the union of the parents' gametes, so it will have the genotype <em>lb/LB</em>
<h3><u>F1 test cross</u></h3>
Test crosses involve a homozygous recessive individual.
<u>The homozygous recessive individual</u><u><em> lb/lb</em></u><u> can only produce 1 type of gamete:</u>
<u>The F1 individual </u><em><u>lb/LB</u></em><u> can produce 4 types of gametes:</u>
- lb - parental
- LB - parental
- lB - recombinant
- Lb - recombinant
Answer:
The correct answer would be non-disjunction.
Down syndrome refers to the genetic disease caused by the non-disjunction of chromosome number 21.
Non-disjunction refers to the event in which the homologous chromosomes or sister chromatids fail to separate properly during a cell division.
In Down syndrome, the sister chromatids of chromosome 21 fail to separate properly which results in the formation of a gamete with 2 copies of chromosome 21.
When this gamete fertilizes with another gamete, it results in the formation of a zygote with 47 chromosomes, that is, 46 chromosomes + extra copy of chromosome 21.