Science - Biology Pt.1 Flashcards
(37 cards)
allele
- variations on a gene for a particular characteristic
- alternate forms or varieties of a gene
asexual
- reproduction that doesn’t involve sex
- offspring arise from a single organism, and inherit the genes of that parent only; it does not involve the fusion of gametes and almost never changes the number of chromosomes.
cell
- basic unit of all living things
- smallest unit of life that can replicate independently
- consist of cytoplasm enclosed within a membrane, which contains many biomolecules such as proteins and nucleic acids.
characteristic
- feature passed onto offspring
- a feature or quality belonging typically to a person, place, or thing and serving to identify them.
chromosome
- threadlike structure consisting of DNA/genes, found in the cell’s nucleas
- Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.
diploid
- name for the normal number of chromosomes in a non-sex cell
- containing two complete sets of chromosomes, one from each parent.
- **2 SETS Not 1 which is haploid
dominant
- an allele that masks the presence of a recessive allele in the phenotype
- seen in offspring
gamete
- process by which organisms produce offspring
-cell that fuses with another cell during fertilization (conception) in organisms that sexually reproduce.
a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote.
generation
- offspring of the same set of parents
genetics
- the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.
genotype
- genetic makeup of an individual
haploid
- Haploid cells have half the number of chromosomes (one complete set of chromosomes)
heterozygous
- having 2 kinds of allele for a particular characteristic
- cells contain two different alleles of a gene
homozygous
- having the same alleles for a particular characteristic
- identical pairs of genes for any given pair of hereditary characteristics
meiosis
- how sex cells reproduce
- chromosomes are copied, paired up and separated to create eggs or sperm.
mitosis
- how most cells reproduce
- part of the cell cycle in which chromosomes in a cell nucleus are separated into two identical sets of chromosomes, and each set ends up in its own nucleus.
offspring
progeny (children) of a plant or animal
recessive
- characteristic masked by the dominant one
- masked in the phenotype by the presence of a dominant allele.
reproduction
- biological process by which new individual organisms – “offspring” – are produced from their “parents”.
- undamental feature of all known life; each individual organism exists as the result
species
a group of similar organisms capable of interbreeding
- basic units of biological classification and a taxonomic rank
sperm
- male sex cell
zygote
- result of a sperm fertilising an ovum
- cell that is formed when a sperm and an ovum combine their chromosomes at conception.
- contains the full complement of chromosomes
- potential of developing into an entire organism.
James Watson
coworker with francis crick, involved in DNA research (DNA structure, Molecular Structure of Nucleic Acids)
Gregor Mendel
- his laws of inheritance are the basis of modern genetics