Science - Biology Pt.1 Flashcards
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
sex cell
a gamete, either a sperm or an ovum. (meiosis)
purebred
offspring that are the result of mating between genetically similar kinds of parents
proteins
any of a large number of complex organic molecules that are composed of one or more chains of amino acids.
Punnett square
a simple graphical method of showing all of the potential combinations of offspring genotypes that can occur and their probability given the parent genotypes.
phenotype
observable or detectable characteristics of an individual organism
amino acids
small molecules that are the components of proteins.
DNA
deoxyribonucleic acid
- a large organic molecule that stores the genetic code for the synthesis of proteins.
genome
genetic material of an organism (complete set of genetic instructions)
contains all of the information needed to build that organism and allow it to grow and develop.
- the full genetic complement of an individual (or of a species).
- humans each individual possesses approximately 2.9 billion base units in their DNA.
ovum
a female sex cell or gamete.
mutation
an alteration of genetic material such that a new variation is produced.
hybrids
offspring that are the result of mating between two genetically different kinds of parents
gene pool
all of the genes in all of the individuals in a breeding population.
gene flow
the transference of genes from one population to another, usually as a result of migration
