Physical Basis of Heredity Notes

Flashcards covering key vocabulary terms from the lecture notes on the physical basis of heredity. These cards are designed to help you review and prepare for your upcoming exam.

Plasma membrane

Defines the cell boundary and delimits the cell from its immediate external environment; actively controls movement into and out of the cell

Cellulose

Major polysaccharide component of plant cell walls.

Glycocalyx

Covering of the plasma membrane in animal cells, composed of glycoproteins and polysaccharides, providing biochemical identity at the cell surface.

Nucleus

Membrane-bound structure in eukaryotes that houses the genetic material, DNA, complexed with proteins into chromatin.

Nucleolus

Amorphous component in eukaryotes where ribosomal RNA (rRNA) is synthesized and ribosome assembly occurs.

Nucleoid

Site in prokaryotes (eubacteria) where the genetic material, a long, circular DNA molecule, is compacted.

Cytoplasm

The region external to nuclear organelles containing cytosol (nonparticulate, colloidal material) and cytoskeleton (support structures).

Cytoskeleton

A lattice of support structures within the cell comprised of microtubules and microfilaments to maintain cell shape, facilitate cell mobility and anchor organelles.

Endoplasmic reticulum

Compartmentalizes the cytoplasm in eukaryotes, increasing the surface area available for biochemical synthesis; can be smooth (synthesizing fatty acids and phospholipids) or rough (studded with ribosomes).

Ribosomes

Sites where genetic information contained in messenger RNA (mRNA) is translated into proteins.

Mitochondria

Sites of the oxidative phases of cell respiration, generating large amounts of ATP.

Chloroplasts

Associated with photosynthesis, the major energy-trapping process on Earth, found in plants, algae and some protozoans.

Centriole

Pair of cytoplasmic bodies located in the centrosome, associated with the organization of spindle fibers for mitosis and meiosis; may be derived from the basal body associated with cilia and flagella.

Spindle fibers

Organized by centrioles and play an important role in the movement of chromosomes as they separate during cell division; composed of microtubules consisting of polymers of the protein tubulin.

Centromere

Constricted region of a chromosome.

p arm

Short arm of a chromosome ('p' for petite).

q arm

Long arm of a chromosome.

Diploid

The diploid number of chromosomes (2n) found in somatic cells.

Haploid

The haploid number of chromosomes (n) found in gametes.

Genome

Genetic information contained in a haploid set of chromosomes.

Locus

Gene sites located along homologous chromosomes.

Karyokinesis

Nuclear division, part of cell division.

Cytokinesis

Cytoplasmic division, partitioning the volume into two parts and enclosing each new cell in a distinct plasma membrane.

Crossing over

Genetic exchange between members of each homologous pair of chromosomes prior to one or the other finding its way into a haploid gamete or spore

cdc mutations

Cell division cycle mutations including kinases and cyclins.

Spermatogenesis

The process in males by which spermatogonia develop into mature spermatozoa

Oogenesis

The process in females by which primary oocytes develop into a mature ovum