Genetics Flashcards
What are chromosomes?
Chromosomes are the instructions for all of a organisms traits which are within the nuclei of a cell. Chromosomes are made up of DNA and contain heredity codes and instructions.
What is genetics?
Genetics is the inheritance of biological traits (characteristics).
What is inheritance?
Inheritance is the passing of traits from parent to offspring, it occurs via reproduction.
Why must a organism have a full set of chromosomes?
A organism must have a full set of chromosomes/introductions for each body cell to function normally, therefore chromosomes are duplicated before reproduction.
What are the two types of reproduction? What are each of them.
Asexual reproduction is when offspring is produced from only 1 parent through the process of BINARY FISSION, = Mitosis
Sexual reproduction is when offspring are produced from two parents, each parents donates a special sex cell called gametes, which are formed from meiosis.
What is a gamete, how do they function? How many chromosomes do they have? What is there purpose?
A gamete is a sex cell which is a product of meiosis. Each gamete contains only half of the full number of chromosomes, which is a haploid (n). Two gametes fuse together in a process called fertilization producing a zygote, with a full a full chromosome number of 46 (2n).
Where does meiosis occur? What is it’s purpose. How does it work.
Meiosis occurs in the germ cells of the gonads (ovaries and testies). These go through the cell cycle G1, S, G2, M (Meiosis).
Where does crossing over occur.
Prophase 1
Where does dna get replicated and why.
DNA gets replicated during interphase, which occurred before meiosis. It’s replication makes chromosomes double stranded.
What is a name for a pair of chromosomes in prophase 1?
During prophase 1 chromosomes pair up with other chromosomes that are the same size, In a process called SYNAPSIS, which form tetroids, and homologous chromosomes.
What is interkinesis?
Interkinesis is the resting stage between meiosis 1 and meiosis 2, chromosomes do not replicate during this stage.
What does meiosis 1 do?
Reduces chromosome number.
What does meiosis 2 do?
Meiosis 2 determines the number of gametes.
