BioScience Dictionary

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Ot.

Found Zygote 35 times.

Displaying results 1 to 10.

1. Alpha1-antitrypsin
This is a protease inhibitor (Pi). Low serum levels of this antienzyme predisposes patients to early onset of emphysema and chronic liver disease. Ten percent of the adult population has the heterozygote genotype MZ in which intermediate levels of alpha1-antitrypsin is present. The incidence of liver disease in MZ is only mildly higher than the general population. (Normal ranges by genotype: normal MM: more than 250mg/deciliter, heterozygous MZ: 50 - 250 mg/dL, homogygous ZZ: less than 50 mg/dL)

2. Anisogamy
A condition where the gamete s of a species have different sizes. In general, the smaller, more mobile gamete is "male" and the larger one which is packed with food and other things to give the potential zygote a good start (and is less mobile as a result) is the "female." The principle behind anisogamy is a division of the labor necessary for two gametes to unite and successfully develop.

3. Balanced stock
A genetic strain of any of several lab organisms (like fruit flies) which can be maintained as heterozygous individuals without requiring constant artificial selection for the heterozygotes, due to a number of lethal recessive gene s with the result that the homozygous females are sterile (unable to produce offspring) and the males with the wrong recessive alleles are dead. (Male fruit flies are not homozygous or heterozygous because they only have one allele per particular genetic loci in question).

4. Blastomere
One of the cell s of the early embryo , formed during the first few divisions of the newly-fertilized zygote .

5. Blastula
A ball of cells surrounding a fluid-filled cavity (the blastocoel) that is produced by the repeated cleavage of a zygote .

6. Cell fusion
The process in which two different cell s fuse into one single cell. The resulting cell has all of the contents from the original cells and has one nucleus containing the genetic material from both of the original cells. This occurs naturally during sexual reproduction , when gamete s ( egg s and sperm ) fuse to produce the zygote , and can also occur under laboratory conditions between somatic cells (any cell other than a gamete).

7. Cleavage furrow
A furrow which forms on an animal cell , indicating imminent cell division into two daughter cells, especially during the first few cellular divisions of a newly-fertilized animal zygote .

8. Codominance
A type of inheritance in which heterozygotes fully express both alleles .

9. Complete dominance
The type of inheritance in which both heterozygotes and dominant homozygotes have the same phenotype .

10. Developmental biology
The study of how a multicellular organism develops from its early immature forms ( zygote , larva, embryo , etc.) into an adult.

View web definitions »

Learn more about Zygote »