BIOL 1406 TERMS

Prokaryotic Cells

Single celled organism with no nucleus and membrane-bound organelles

Eukaryotic Cells

Multi-cellular organism with a nucleus and membrane-bound organelles

Cell wall (plants and bacteria)

Outer layer of the cell which provides structure, shape, and protection

Cell membrane (plasma membrane)

Regulates the passage of substances in and out of the cell

Cytosol

Liquid part of the cytoplasm, made up of mostly water

Cytoplasm

Enter content within the cell membrane, helps hold organelles in place

Mitochondria

Powerhouse of the cell, produces chemical energy for the cell

Golgi Apparatus

“Post office”, receives proteins/lipids from ER and delivers to other organelles

Rough Endoplasmic Reticulum

Synthesizes/creates proteins and contains ribosomes

Nucleus

Holds all the DNA for the cell

Centrioles

Organizes microtubules for cell division and the formation of cilia and flagella

Ribosomes

The site of protein synthesis in the cell

Chloroplast

Photosynthesizes by converting light energy into glucose and oxygen

Gamete Cells

Reproductive cells (sperm and egg)

Somatic Cells

Body cells (all other cell besides reproductive)

Viruses

Parasites, they infect a host cell and replicate

Smooth Endoplasmic Reticulum

Synthesizes lipids steroids and carbs, detoxifies harmful substances and stores calcium ions

Bacteriophage

Type of virus that infects bacterial cells

Atom Elements

small unit made up of 1 kind of atom (pure substances)

Molecules

a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.

Subatomic particles

protons, electrons, and neutrons

Proton

positively charged, gives the atom its identity (atomic #)

Neutron

no charge, can be any number of it in atom

Electron

negatively charged, same amount as protons

Nucleus of atom

central core of an atom made of protons and neutrons

Organic compound

chemical substance that contains carbon

Inorganic compound

chemical substances that generally do not contain carbon

Fredrick Griffith

discovered transformation (bacteria can transform their own genes that they pick up from other bacteria) - discovered by isolating 2 different strains of bacteria

Avery (& Macleod & McCarty)

discovered that genes are made of DNA - discovered by using leftover research from Griffith

Hershey and Chase

discovered that DNA carried the genetic code - discovered by radioactively labeling sulfur and phosphorus

Watson and Crick

discovered that DNA was a double helix structure - discovered by using Rosalind Franklin’s picture

Histone(s)

proteins in eukaryotic cells that bind to DNA to form chromatin

Nucleosome

a section of DNA that is wrapped around a core of proteins

Chromatin

what chromosomes are made up of

Chromosome

condensed chromatic

Homologous Chromosome

one of a pair of chromosomes in a diploid cell that have the same genes in the same order

Autosomes

chromosomes that are not sex chromosomes

Sex chromosomes (Xand Y)

chromosomes that determine gender and hold sex linked traits

Aneuploidy

alteration in the # of chromosomes

Chromatid

one of the two structures that make up a chromosome

Sister chromatids

two identical strands of DNA that are produced when a chromosome replicates, joined together at a common centromere until they separate during cell division

Genes

DNA sequence that codes for a protein

RNA molecule

single stranded, makes up messenger, ribosomal, and transfer

DNA strand

double-stranded helix resembling a twisted ladder, composed of nucleotide units that carry genetic information

RNA strand Polypeptide Protein

serves as a template for protein synthesis by carrying genetic instructions from DNA

DNA replication/ DNA synthesis

semi-conservative process where a cell's DNA is copied to make two identical DNA molecules

Gene expression/ protein synthesis

reading a gene's instructions to create a functional product, typically a protein or a functional RNA molecule

Nucleotide (parts)

phosphate group, 5 carbon sugar, and nitrogen base

Pyrimidine

cytosine and thymine

Purines

adenine and guanine

Polynucleotide

complex molecule, like DNA or RNA, that is a polymer of smaller units called nucleotides

Antiparallel

orientation of the DNA strand

5’ end

“top” of DNA strand

3’ end

where new DNA molecules are added to

DNA helix/ double helix

structure of DNA

Heredity Genetics

biological process where genetic traits are passed from parents to offspring through DNA and genes

Trait

any characteristics of an individual

Genotype

organisms genetic composition (TT, tt)

Phenotype

form of a trait that organism displays

Hybrid

offspring from the cross of two individuals of the same species

Parental (P) generation First

parental generation

Second Filial (F2) generation

2nd fillial

Filial (F1) generation

monohybrid cross (first fillal)

Dominant (trait, gene, phenotype)

trait that is expressed in heterozygous state

Recessive (trait, gene, phenotype)

trait that is masked in the heterozygous state

Allele(s)

different forms of a gene (letters)

Locus (loci)

specific place on a chromosome

Homozygous Dominant

same allele, produces trait that is expressed

Homozygous recessive

same allele, produces trait that is masked 

Heterozygous

two different alleles

Monohybrid cross

genetic cross between two individuals for one trait

Dihybrid cross

genetic cross between two individuals with two different traits

Test cross

crossing an unknown genotype with a homo recessive

Mitosis

cell duplication in which one cell divides into two genetically identical daughter cells

Meiosis I

first stage of meiosis, a type of cell division that reduces the chromosome number by half, results in two haploid cells

Interphase

G1, S, G2 (non-dividing)

M phase

division of cell nucleus and cytokinesis (mitosis)

Cytokinesis

division of cytoplasm following mitosis

Diploid

two complete sets of chromosomes (2n)

Haploid

one complete set of chromosomes (n)

Zygote

fertilized egg

Tetrad

pair of homologous chromosomes, each with two sister chromatids, form to make one structure

Crossing-over

homologous chromosomes exchange genetic material during Prophase I

Genetic Recombination

process of exchanging or combining genetic material, resulting in new DNA molecules or new combinations of genes (crossing over)

G1 Phase

cell growth, duplication of organelles, preparation for DNA replication

S phase

DNA replication, chromosomes are copied

G2 Phase

cell growth, duplication of organelles and prepares for division

Prophase I

homologous chromosomes pair to make tetrads, nuclear envelope breaks down, homologs attach to microtubules and crossing over occurs

Metaphase I

tetrads line up at metaphase plate, alignment is random

Anaphase I

homologous chromosomes separate and move to opposite sides, and sister chromatids remain attached at their centromeres 

Telophase I

one of each pair of homologous chromosomes is at each pole

Prophase II

chromosomes condense again, DNA does not replicate again, one spindle attaches to centromeres of sister chromatids

Metaphase II

chromosomes line up on metaphase plate 

Anaphase II

sister chromatids separate and chromosomes move 

Telophase II

nuclei form, cytokinesis happens

Meiosis II

two haploid cells produced in meiosis I undergo another division, resulting in four genetically distinct haploid gametes

DNA Polymerase I

enzyme that catalyzes DNA synthesis 

DNA helicase

breaks hydrogen bonds and separates DNA strands

Topoisomerase

cuts and rejoins DNA to relieve tension down the helix

Single strand binding proteins

attaches to separate DNA to prevent closing