biomed final study guide

Diffusion

Movement of molecules from HIGH to LOW concentration, no energy needed

Osmosis

Diffusion of water across a semipermeable membrane

Isotonic solution

Same solute concentration inside and outside the cell, water moves in and out equally, cell stays the same

Hypotonic solution

More water outside the cell → more water rushes in → cell swells or bursts (lysis in animal cells)

Hypertonic solution

More water inside the cell → water leaves → cell shrivels up

Semipermeable membrane

Only lets certain things through

Lysis

When a cell bursts due to too much water intake

Turgid

A plant cell filled with water

Passive transport

No energy needed, molecules move down their gradient

Active transport

Needs energy (ATP) to move molecules AGAINST their concentration gradient

Facilitated diffusion

Passive, but uses transport proteins to help stuff move across membranes

Gram positive bacteria

THICK peptidoglycan wall

Stains PURPLE

No outer membrane

Gram negative bacteria

THIN peptidoglycan wall

Stains PINK

Has an outer membrane

Gram staining process

Crystal violet → iodine → alcohol → safranin

Prokaryote

No nucleus, small and simple

Eukaryotes

Nucleus, big and detailed

DNA and RNA polymers are made up of what

Nucleotides

How many amino acids are there

20

DNA replication

DNA unzips (helicase), new bases added (DNA polymerase) → end result - 2 identical DNA strands

Codon

A group of 3 mRNA bases that code for an amino acid

Genome

All the genetic information in an organism

Phenotype

Physical traits you can SEE

Genotype

Your actual DNA makeup

Nucleotide

Sugar + phosphate + base = 1 nucleotide (building block of DNA and RNA)

Transcription

DNA → mRNA (in the nucleus)

Translation

mRNA → protein (in the ribosome) product = amino acid chain

mRNA table

Use the codon (3 letters) to match with the correct amino acid

Pedigrees

Circles - female

Square - male

Shaded - has trait

Unshaded - doesnt have trait

Half-shaded - carrier

Punnet square

Shows possible gene combos

Sickle cell anemia

Caused by a mutation in the hemoglobin gene

Makes red blood cells a sickle—shape

Hemophilia

Blood doesnt clot properly

Usually passed down via X-linked recessive inheritance

Karyotypes

A visual of all your chromosomes

Normal = 46 chromosomes (23 pairs)

Common chromosomes abnormalities

Down syndrome

Turner syndrome

Klinefelter syndrome

Down syndrome

Trisomy 21 (3 copies of chromosome 21)

Turner syndrome

Only 1 X chromosome

Klinefelter syndrome

XXY