Reproduction & Heredity Flashcards
DNA
a molecule that contains the information that determines the traits that a living thing inherits and needs to live
Chromosomes
visible structures of DNA, which contain two chromatids joined together by a centromere
Cell Cycle
the life cycle of a eukaryotic cell. It is divided into 3 stages: interphase, mitosis, and cytokinesis
Interphase
the part of the cell cycle when it is not dividing. The cell grows twice its size and produces organelles. It transports materials and gets rid of wastes
Mitosis
the part of the cell cycle in which the nucleus divides; the second phase of the life cycle of a eukaryotic cell
Cytokinesis
the division of the parent cell’s cytoplasm, when the membrane pinches inward between the two nuclei and forms two complete cells.
Prophase
the chromatin in the nucleus condenses and becomes visible under a microscope
Metaphase
chromosomes line up in the middle of the cell
Anaphase
the chromatids separate and are pulled to opposite sides of the cell
Telophase
the last phase of mitosis, when each cell now has its own nucleus and the cycle begins again
Meiosis
the type of cell division that produces haploid cells such as eggs and sperm cells
Homologous chromosomes
chromosomes found in pairs that have the same structure and size
Sexual reproduction
two parents each contribute a sex cell to the new organism
Asexual reproduction
one organism produces one or more new organisms that are identical to itself. This occurs through mitosis.
Fertilization
when a sperm and egg cell join together to form an embryo
Binary fission
the form of asexual reproduction in prokaryotes. The parent organism splits itself in two, producing two new cells
Budding
an organism develops tiny buds on its body. The buds grow to form full-size organisms that are genetically identical to the parent
Spores
specialized cells that can survive harsh conditions. They are produced asexually by one parent
Vegetative reproduction
new plants grow from a part of the existing plant, like stems, roots, or leaves.
Heredity
the passing of genetic material from parents to offspring
Dominant
shown with a capital letter, these traits are guaranteed to appear in offspring
Recessive
shown with a lower-case letter, these traits contribute to the phenotype only when two copies of it are present
Gene
segments of DNA found in chromosomes that give instructions for producing a certain characteristic
Allele
different versions of a gene found in DNA
Genotype
the combination of alleles inherited from your parents
Phenotype
your observable traits
Incomplete dominance
one trait is not completely dominant over the other. The phenotypes blend together to create a new shade, such as hair or eye color.
Codominance
both the alleles in the heterozygous individual contribute to the phenotype. The traits don’t blend together-the person has BOTH traits.
Punnett Square
a graphic used to predict the possible genotypes of offspring in a given cross. It shows all the possible allele combinations in the offspring.
Probability
expressed as a percentage, it is the mathematical chance of a specific outcome in relation to the total number of possible outcomes
Ratio
an expression that compares two quantities, like 1:4 or “one to four.”
Pedigree
a tool used to study patterns of inheritance through generations of a family.
