NATS 1675 EXAM #2 2025
QUESTIONS AND ANSWERS
Species - ....ANSWER ...-population of organisms that retain their
individuality in nature because they are reproductively isolated from other species
around them. Reproductive isolation includes both behaviour and genetics.
Genotypes - ....ANSWER ...-genetic makeup of an organism, e.g., RR, Rr or
rr; the combination of alleles at a particular locus, or all loci.
Phenotype - ....ANSWER ...-The appearance of an organism with regard to
an inherited characteristic (Trait) or all inherited characteristics. The phenotype is
produced by the genotype in cooperation with the the environment, e.g., R =
round pea seeds, r = wrinkled pea seeds.
Locus (loci pl.) - ....ANSWER ...-Location of a gene on a chromosome.
Locus is sometimes used synonymously for 'gene'
Allele - ....ANSWER ...-a pair of genes that occupy corresponding positions
on homologous chromosomes. (Remember - it is homologous chromosomes that
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,pair during prophase I). Alleles are also 1 of 2 or more alternate forms of a gene
that occupy a particular locus on homologous chromosomes.
Dominant - ....ANSWER ...-A trait that appears in the phenotype whenever
2 alleles (genes) for the trait are present in the genotype. e.g., RR or Rr = round
seeds
Recessive - ....ANSWER ...-A trait that appears in the phenotype only when
2 alleles for the traits are present in the genotype. e.g., rr = wrinkled seeds
Homozygous - ....ANSWER ...-Alleles of a gene on homologous
chromosomes are alike.
Heterozygous - ....ANSWER ...-Alleles of a gene on homologus
chromosomes are not alike.
Carrier - ....ANSWER ...-A heterozygous individual (organism) of normal
phenotype who has a hidden recessive allele in its genotype and thus can transmit
the recessive allele to offspring. ' Carrier' can imply a possibly damaging or
unwanted gene.
Mitosis - ....ANSWER ...-A kind of cell division in which two identical cells
are produced. It is used as one method of reproduction for single celled
microorganisms such as protests and bacteria. It is also the type of cell division
that occurs in multicellular organisms for growth, repair, and replacement.
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, Meiosis - ....ANSWER ...-A process of cell division by which gamates
containing half the normal number of chromosomes are produced. Meiosis is also
called reduction division. (Cutting # of chromosomes in half [half sperm, half egg
chromosomes come together to = 46 chromosomes]).
Gamates - ....ANSWER ...-sex cells, e.g., egg cells, sperm cells, pollen grains.
Chromosome - ....ANSWER ...-A strand of DNA and protien found in the
nucleus of a cell; carries genetic information.
DNA - ....ANSWER ...-deoxyribonucleic acid, the chemical molecule that
transmits a particular hereditary trait. A gene can be linked to a set of blueprints.
Trait - ....ANSWER ...-Genetic chatacteristic
Homologous Chromosomes - ....ANSWER ...-A pair of chromosomes (1
from mom & 1 from dad) that carry genetic information for the same traits, e.g.,
eye colour, hair colour, etc.
Diploid - ....ANSWER ...-Having the normal paired homologous
chromosomes of somatic cells; also referred to as ' 2N'
Somatic cells - ....ANSWER ...-Body cells
Diploid = 2N = 46
Haploid = 1N = 23
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QUESTIONS AND ANSWERS
Species - ....ANSWER ...-population of organisms that retain their
individuality in nature because they are reproductively isolated from other species
around them. Reproductive isolation includes both behaviour and genetics.
Genotypes - ....ANSWER ...-genetic makeup of an organism, e.g., RR, Rr or
rr; the combination of alleles at a particular locus, or all loci.
Phenotype - ....ANSWER ...-The appearance of an organism with regard to
an inherited characteristic (Trait) or all inherited characteristics. The phenotype is
produced by the genotype in cooperation with the the environment, e.g., R =
round pea seeds, r = wrinkled pea seeds.
Locus (loci pl.) - ....ANSWER ...-Location of a gene on a chromosome.
Locus is sometimes used synonymously for 'gene'
Allele - ....ANSWER ...-a pair of genes that occupy corresponding positions
on homologous chromosomes. (Remember - it is homologous chromosomes that
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 1
,pair during prophase I). Alleles are also 1 of 2 or more alternate forms of a gene
that occupy a particular locus on homologous chromosomes.
Dominant - ....ANSWER ...-A trait that appears in the phenotype whenever
2 alleles (genes) for the trait are present in the genotype. e.g., RR or Rr = round
seeds
Recessive - ....ANSWER ...-A trait that appears in the phenotype only when
2 alleles for the traits are present in the genotype. e.g., rr = wrinkled seeds
Homozygous - ....ANSWER ...-Alleles of a gene on homologous
chromosomes are alike.
Heterozygous - ....ANSWER ...-Alleles of a gene on homologus
chromosomes are not alike.
Carrier - ....ANSWER ...-A heterozygous individual (organism) of normal
phenotype who has a hidden recessive allele in its genotype and thus can transmit
the recessive allele to offspring. ' Carrier' can imply a possibly damaging or
unwanted gene.
Mitosis - ....ANSWER ...-A kind of cell division in which two identical cells
are produced. It is used as one method of reproduction for single celled
microorganisms such as protests and bacteria. It is also the type of cell division
that occurs in multicellular organisms for growth, repair, and replacement.
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 2
, Meiosis - ....ANSWER ...-A process of cell division by which gamates
containing half the normal number of chromosomes are produced. Meiosis is also
called reduction division. (Cutting # of chromosomes in half [half sperm, half egg
chromosomes come together to = 46 chromosomes]).
Gamates - ....ANSWER ...-sex cells, e.g., egg cells, sperm cells, pollen grains.
Chromosome - ....ANSWER ...-A strand of DNA and protien found in the
nucleus of a cell; carries genetic information.
DNA - ....ANSWER ...-deoxyribonucleic acid, the chemical molecule that
transmits a particular hereditary trait. A gene can be linked to a set of blueprints.
Trait - ....ANSWER ...-Genetic chatacteristic
Homologous Chromosomes - ....ANSWER ...-A pair of chromosomes (1
from mom & 1 from dad) that carry genetic information for the same traits, e.g.,
eye colour, hair colour, etc.
Diploid - ....ANSWER ...-Having the normal paired homologous
chromosomes of somatic cells; also referred to as ' 2N'
Somatic cells - ....ANSWER ...-Body cells
Diploid = 2N = 46
Haploid = 1N = 23
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