Ohio University BIOS 1300 Exam 2

example of an amphipathic molecule

stearic acid

glycolipid

lipid with sugar

example of weakly amphipathic molecule

cholesterol

hydrophobic regions

lots of non-polar side chains

hydrophilic regions

lots of polar and ionic side chains

selectively permeability based on

hydrophobic/hydrophilic and size

example of small hydrophobic molecule

O2

example of small uncharged polar molecule

H2O

example of larger uncharged polar molecule

glucose

example of ion

Na+

integral proteins

embedded, partially/entirely through and amphipathic

transmembrane

entirely through

peripheral proteins associate with

phospholipids or integral proteins

glycoprotein

chains of sugars covalently linked to a protein

channel proteins

ion channels for specific ions, constantly open

gated channel

channel that open/closes

aquaporins

channels for water, faster osmosis

carrier proteins

help smallish specific polar molecules to cross, can change shape

cell-adhesion molecules

bind cell to another cell, or anchor cell to extracellular matrix

cell identity markers

glycoprotein that allows cells to identify foreign cells

receptor protein

relay messages from exterior to interior

ligand

messenger molecule that binds to its receptor

example of an enzyme that's a membrane protein

maltase

ligand-receptor has _______ binding

transient

receptor to a ligand

transmembrane protein

order of steps of bio signaling

1. reception 2. transduction 3. response

transduction

carrying message into cell interior, relaying, amplifying

cAMP stands for

cyclic adenosine monophosphate

cAMP is made from

ATP

G-protein coupled receptors

activate associated G proteins, cascade

concentration gradient _____ pass through membrane easily

can't

concentration gradient

region along which concentration changes

resting cell membrane potential

70mv - -90mv

electrochemical gradient

separation of ions across a membrane

diffusion

molecules move from high to low concentration

osmosis

water moves from low solute concentration to high solute concentration

reverse osmosis

way to purify water

cells in hypotonic solution _______

lysing

lysing = _______

explode

crenation = ______

shrivel

cells in hypertonic solution ________

crenation

passive transport

no energy required

example of simple diffusion

diffusion, osmosis

example of facilitated diffusion

channel and carrier proteins

active transport

requires energy, low to high concentration, against gradient

active transport example

protein pumps

bulk transport

vesicles

simple diffusion

substance passes directly through lipid bilayer

facilitated diffusion

substance needs help to pass through membrane

3 Na+ ______

out

2 K+ _____

in

inside of sodium potassium pump =

negative

outside of sodium potassium pump =

positive

_____ can be stored in a gradient

energy

cotransport

transport of 2 or more solutes at the same time

cotransport requires ______________________

cotransporter protein

cotransport can be either ______________

symporter or antiporter

secondary active transport

energy stored in Na+ gradient from ATP

secondary active transport is used to ______________

transport solute against gradient

example of secondary active transport

glucose

vesicles

little membrane bubbles inside cell (phospholipids)

microtubules are

train tracks for intracellular vesicle transport

ex of microtubule

kinesin

ex of secretion

insulin

3 types of endocytosis

phagocytosis, pinocytosis, radiator-mediated endocytosis

pinocytosis is

cell drinking random contents of vesicles

receptor-mediated endocytosis is

receptors on cell surface grab target molecules

receptor-mediated endocytosis collects _______ molecules

specific

phagocytosis

cell eating

pseudopodia

limb-like structures that form to capture foreign materials

phosphate end is

5'

free OH end is

3'

new nucleotides add to the ___ end

3'

chromatin

DNA + protein packed into a chromosome

chromosome

1 DNA molecule + proteins

centromere

narrow middle part of chromosome

XX =

female

XY =

male

46 chromosomes breakdown

55 autosomes and 2 sex

human genome project

ended in 2003 and lasted 13 years

ribosomes

made of protein and RNA, site of protein synthesis, switch locations

order of how polypeptide is made

DNA --> RNA ---> protein

info in ___ is transferred to _____ , ______ moves along _____

DNA, messenger RNA, ribosome, mRNA

symporter

going same direction

antiporter

going opposite direction

_______ is threaded into ER from ________

polypeptide, ribosome

one mRNA ---->

one polypeptide

one gene ---->

one kind of polypeptide

RNA intermediate

carries info, mRNA

transcription

synthesis of RNA from info in DNA

translation

ribosome reads RNA and adds to amino acids

order codons are read --->

5'-3'

5' cap is a

modified guanine nucleotide added to 5' end

poly-a tail adds

adenine to 3' end

exons

segments that code for amino acids

introns

intervening sequences that do not code

mRNA splicing

introns cut out, exons connected together

alternative splicing

cell puts exons together in alternative ways, sometimes not all exons are used

translation

mRNA ----> polypeptide

__________ matches with a ________

anticodon, codon