Homeostasis and Genetics Overview

Homeostasis

Regulation of the internal environment to maintain stability.

Negative feedback loop

Halts or reverses an action to maintain homeostasis.

Positive feedback loop

Reinforces an action to maintain homeostasis.

Sweating to regulate temperature

Example of a negative feedback loop.

Blood clotting

Example of a positive feedback loop.

Osmosis

Movement of solute molecules from high to low concentration.

Diffusion

Movement of solvent molecules from low to high concentration to establish equilibrium.

Solute

Substance that can be dissolved into a solution by a solvent.

Solvent

Substance in which a solute is dissolved.

Solution

Homogeneous mixture of solute and solvent.

Hypertonic solution

Solution with higher solute concentration than the cell.

Isotonic solution

Solution with equal solute concentration to the cell.

Hypotonic solution

Solution with lower solute concentration than the cell.

DNA

Deoxyribonucleic acid storing genetic information.

Nucleotide

Basic building block of a DNA molecule with sugar, phosphate, and base.

Complementary base pairing

Base pairing in the double-stranded DNA helix based on nitrogen bases.

Transcription

Process of creating mRNA from DNA template.

Translation

Process of creating a protein from mRNA using tRNA anticodons.

RNA

Single-stranded nucleic acid with Uracil.

Mutation

Change in the DNA sequence of a gene.

Arteries

Blood vessels that carry blood away from the heart.

Veins

Vessels that carry blood back to the heart.

Capillaries

Vessels facilitating exchange of oxygen, nutrients, and waste materials between blood and body cells.

Ectotherms

Cold-blooded animals relying on external sources to regulate body temperature.

Endotherms

Warm-blooded animals generating heat internally.

Monomer

Molecule binding to others to form a polymer. Monomers: Proteins=Amino Acids, Nucleic Acids=Nucleotides, Carbohydrates=Monosaccharides, Lipids=Fatty Acids and Glycerol.

mRNA

Resulting from DNA sequence GAT-TAC-AGA-TTA-CAT is CUA-AUG-UCU-AAU-GUA.

Gregor Mendel

Biologist who developed three principles of inheritance.

Genetics

Study of genes and how traits pass between generations.

Heredity

Passing of genes and genetic traits from parent to offspring.

Phenotype

Observable traits determined by genetic makeup.

Genotype

Unique DNA sequence representing inherited gene forms.

Sex linked trait

Trait determined by gender due to correlation with 23rd pair of chromosomes.

Allele

Gene version at a specific chromosome position.

Dominant allele

Overruling allele causing a specific phenotype, represented by uppercase letter.

Recessive allele

Allele overruled by dominant allele, represented by lowercase letter.

Punnett Square

Used to predict genotypes of offspring from parental genotypes.

Homozygous

Genotype with two identical alleles.

Heterozygous

Genotype with two different alleles.

Autosomal dominant

Trait expressed in presence of one copy of the gene.

Evolution

Species characteristics change over generations due to natural selection.

Natural selection

Survival of traits based on environment, leading to differential reproduction.

Vestigial structures

Features in animals that lost original function through evolution.

Homologous structures

Similar features in organisms from common ancestry with potentially different functions.

Analogous structures

Features in species with similar functions but different structures due to similar environmental pressures.

DNA evidence in evolution

Supports shared ancestry and physical changes due to natural selection.

Galapagos islands

Islands where Darwin studied evolution.