HSC Biology

Asexual reproduction

Process by which a single parent reproduces by itself

Sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents

External fertilisation

The process by which the female lays eggs and the male fertilizes them once they are outside of the female

Internal fertilisation

fertilization of an egg by sperm that occurs inside the body of a female

Budding

Asexual reproduction in which a part of the parent organism pinches off and forms a new organism

Spores

Asexual reproductive or resting cell capable of developing into a new organism without fusion with another cell, in contrast to a gamete

Binary fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

Fertilisation

Process in sexual reproduction in which male and female reproductive cells join to form a new cell

Implantation

process in which the blastocyst attaches to the wall of the uterus

Mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes

Meiosis

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.

Watson-Crick Model

the double-helix structure of the DNA molecule

Nucleotide composition

phosphate, sugar, nitrogenous base

Nucleotide pairing

A with T & G with C -- This forms the double helix

Nucleotide bonding

A, T, C, G

Transcription

(genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA

Translation

(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm

mRNA

messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome

Fertilisation in plants

If a pollen grain lands on the stigma of a plant, a pollen tube will grow out of the pollen grain, down through the style to the ovary and into the ovule. A nucleus from the male gamete then moves down the pollen tube and will fuse with the nucleus of the female gamete, which is fertilisation. A fertilised female gamete forms a seeds and the ovary develops into a fruit around the seed.

Hormones

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

Angiosperms

flowering plants

Haploid

(genetics) an organism or cell having only one complete set of chromosomes

Diploid

(genetics) an organism or cell having two sets of chromosomes or twice the haploid number

Testosterone

Male sex hormone

Oestrogen

Female sex hormone which stimulates the lining of the womb to build up in preparation for a pregnancy.

Progesterone

hormone produced by the corpus luteum in the ovary and the placenta of pregnant women

LH (luteinizing hormone)

Produced by Anterior lobe of Pituitary Gland. Targets ovaries and testes to stimulate estrogen secretion and egg maturation; stimulates sperm production.

FSH (follicle stimulating hormone)

a hormone that influences the maturing of eggs and production of sperm

Vegetative propagation

A form of asexual reproduction in which plants produce genetically identical offshoots (clones) of themselves, which then develop into independent plants.

Pollination

transfer of pollen from the male reproductive structure to the female reproductive structure

Germination

the process whereby seeds or spores sprout and begin to grow

DNA replication

DNA unzips into two parts and splits with the cell. In it's new home each side of the DNA strand attack to matching nucleotides to create 2 exact copies. It is important in puberty and other times of growth as it is the reproducing of your cells.

Interphase

Cell grows, performs its normal functions, and prepares for division

Crossing over

Process in which homologous chromosomes exchange portions of their chromatids during meiosis.

DNA

deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.

Gene

A segment of DNA on a chromosome that codes for a specific trait

Chromosomes

threadlike structures made of DNA molecules that contain the genes

Eucaryotes

a cell that differs from a prokaryotic cell chiefly by having a nuclear membrane, organelles, and mitotic cell division

Procaryotes

cellualar organisms that lack a true nucleus

Polypeptide synthesis

The biological Production of peptides. DNA generates mRNA; mRNA moves to the ribosomes, where a tRNA anticodon binds to an mRNA codon, causing amino acids to join together in their appropriate order.

tRNA

transfer RNA; type of RNA that carries amino acids to the ribosome

RNA

single-stranded nucleic acid that contains the sugar ribose

Phenotype

An organism's physical appearance, or visible traits.

Genotype

An organism's genetic makeup, or allele combinations.

Protein

An organic compound that is made of one or more chains of amino acids and that is a principal component of all cells

RNA polymerase

Enzyme that links together the growing chain of ribonucleotides during transcription.

Homologous chromosomes

Chromosomes that have the same sequence of genes and the same structure

Mutation

change in a DNA sequence that affects genetic information

Autosomal

all the other genes in the body that are not sex-linked.

Sex linkage

occurs when certain traits are determined by genes on sex chromosomes

Co-dominance

situation in which both alleles of a gene contribute to the phenotype of the organism

Dominant

Describes a trait that covers over, or dominates, another form of that trait.

Incomplete dominance

A pattern of inheritance in which two alleles, inherited from the parents, are neither dominant nor recessive. The resulting offspring have a phenotype that is a blending of the parental traits.

Multiple alleles

A gene that has more than two alleles

Pedigree

A diagram that shows the occurrence of a genetic trait in several generations of a family.

Punnet Square Method

a method of predicting the genotypes and phenotypes of offspring in genetic crosses

Frequency Data

How often a behavior occurs within a given time frame. The behavior must have a clear start and stop

Single nucleotide polymorphism (SNP)

A single base-pair site in a genome where nucleotide variation is found in at least 1% of the population.

Independant assortment

independant segregation of genes during the formation of gametes

Allele

one of a number of different forms of a gene

Cell cycle

The regular sequence of growth and division that cells undergo

Autosomal dominant

inheritance pattern of a dominant allele on an autosome

Autosomal recessive

two copies of an abnormal gene must be present in order for the disease or trait to develop

Polygenic

trait controlled by two or more genes

Genetics

The scientific study of heredity

DNA sequencing

Determining the exact order of the base pairs in a segment of DNA.

DNA fingerprinting

The analysis of DNA from samples of body tissues or fluids in order to identify individuals.

DNA profiling

A procedure that analyzes DNA fragments to determine whether they come from a specific individual.

Short tandem repeats

(STR) simple sequence DNA containing multiple tandemly repeated units of two to five nucleotides. variations in STRs act as genetic markers in STR analysis, used to prepare genetic profiles

PCR (polymerase chain reaction)

A method of producing thousands of copies of DNA segment using the enzyme DNA polymerase

Electrophoresis

Procedure used to separate and analyze DNA fragments by placing a mixture of DNA fragments at one end of a porous gel and applying an electrical voltage to the gel

Sanger sequencing method

Method used in DNA sequencing

BRCA1 and BRCA2

breast cancer 1 and 2 - genetic mutations associated with increased risk for breast cancer

Mutagen

A chemical or physical agent that interacts with DNA and causes a mutation.

Electromagnetic radiation

a kind of radiation including visible light, radio waves, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously.

Point mutation

gene mutation in which a single base pair in DNA has been changed

Chromosomal mutation

A change in the chromosome structure, resulting in new gene combinations.

Somatic mutation

a mutation that occurs in a body cell

Germ-line mutation

a mutation occurring in gametes; passed on to offspring

Coding DNA

sequences of a gene's DNA (also known as exons) that are coded to produce a specific protein and are transcribed and translated during protein synthesis

Noncoding DNA

Sequences of a gene's DNA (also known as introns) that are not coded to produce specific proteins and are excised before protein synthesis.

Genetic variation

Differences among individuals in the composition of their genes or other DNA segments

Gene flow

movement of alleles from one population to another

Genetic drift

A change in the allele frequency of a population as a result of chance events rather than natural selection.

Gene pool

Combined genetic information of all the members of a particular population

Substitution

A mutation in which a nucleotide or a codon in DNA is replaced with a different nucleotide

Insertion

A mutation involving the addition of one or more nucleotide pairs to a gene.

Deletion mutation

a change in the base sequence of a gene that results from the loss of one or more base pairs in the DNA

Frameshift mutation

involves the insertion or deletion of a nucleotide in the DNA sequence

Nonsense mutation

A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.

Missense mutation

A base-pair substitution that results in a codon that codes for a different amino acid.

Silent mutation

A mutation that changes a single nucleotide, but does not change the amino acid created.

Deletion

A change to a chromosome in which a fragment of the chromosome is removed.

Duplication

change to a chromosome in which part of the chromosome is repeated

Translocation

Change to a chromosome in which a fragment of one chromosome attaches to a nonhomologous chromosome.

Inversion mutation

Mutation in which a chromosome piece reattaches to original chromosome but in reverse orientation

Aneuploidy

the presence of an abnormal number of chromosomes in a cell

Junk DNA

genomic DNA that does not encode proteins, and whose function, if it has one, is not well understood.

Biotechnology

A form of technology that uses living organisms, usually genes, to modify products, to make or modify plants and animals, or to develop other microorganisms for specific purposes.

Social Implications

refer to the positive or
negative impact on an individual or group as a
result of an action or choice made by an individual
or group. The action or choice could be made by
the individual themselves or by another person or
group