U.1 (Genetics🧬): Cell Division & Reproduction vocab

Genetics

scientific study of heredity and variation

Somatic cell

the cells in the body other than sperm and egg cells

Centromere

holds two chromatids together in a pair of chromosomes

Mitosis (PMAT)

when cells divide into two identical ones

Centriole

protein bodies in the cytoplasm that form & organize spindle fibers

Spindle fibres

attaches to centromere to pull sister chromatids apart

Chromosome

structure that contains DNA

→ counted by # of centromeres

Sister chormatid

identical copy of a chromosome, remains attached to it until anaphase

Sex chromosome

type of chromosome that dettermines sex

→ x + x = female → x + y = male

Autosome

any chromosome other than sex chromosomes

Genome

a complete set of DNA in an organism

Gene

segment of DNA, the basic unit of heredity

Allele

a specific form of gene

→ dominant or recessive

Karyotype

a visual representation of homologus pairs

Asexual reproduction

the production of offspring from a single parent; the genetic makeup of the offspring is identical to that of a parent

Sexual reproduction

the production of an offspring when a male gamete (sperm) fertalizes female gamete (egg)

Cancer

uncontrolled cell growth

Apoptosis

state in which a cell self-destructs (kills itself)

Gamete

a sex cell, female (ovum)/ male (sperm)

Haploid

single set of unpaired chromosomes

Diploid

two complete sets of chromosomes, one from each parent

Fertilization

the formation of a zygote by the joining together or formation of two gametes

Zygote

a fertilized egg cell when a male gamete (sperm) enters the female (ovum/egg)

Meisois

a two-stage cell division

Crossing over

the exchange of chromosome segments between homologus pairs during synapsis

Homologous chromsome

matching pair of chromosomes, similar in size and carrying information for the same genes

Synapsis

the fusion of chromosome pairs at the start of meiosis

Spermatogenesis

the production of mature sperm cells

Oogenesis

the production of mature egg cells

Non-disjunction

the failure of homologous chromosomes to move to opposite poles of the cell during meiosis; results in abnormal # of chromosomes in meiosis

Monosomy

absence of one member of a pair of chromosomes

Trisomy

extra chromosome in a homologous pair

In Vitro Fertilization (IVF)

the joining of a woman’s egg and a man’s sperm in a petri dish

Cloning

the process of producing one individual that is genetically identical to another using a single cell or tissue

Recombinant DNA

DNA molecules formed through combining genetic material from different sources

Stem cell

cells that can develop into many different cell types