bio test 2 (copy)

plasma membrane

outer layer of cell

cytoskeleton

internal protein network for support/transport

cytosol

jelly like fluid in the cell

cytoplasm

the space between the nucleus and plasma membrane

organelles

perform cellular functions

endomembrane system

organelles connected by membranes or exchange membrane bound transport vesicles

organelles job

protein production pathway

nucelus

contain DNA
DNA is instructions to build proteins
surrounded by nuclear envelope
"double membrane"- contains pores

nuclear envelope

membrane barrier that separates the nucleus from the cytoplasm

mRNA

messenger RNA
"photocopy" of DNA instructions

nucleolus job

produces ribosome subunits

ribosome job

protein synthesis

if ribosome is free in cytoplasm then

the proteins are used in the cytosol

if ribosomes is bound to the rough ER then

the proteins are exported from the cell

rough endoplasmic reticulum

membrane network
lined with ribosomes

rough ER main functions

modifies proteins
eliminates faulty proteins
produce membrane

ER lumen

continuous space within nuclear envelope

smooth endoplasmic reticulum

enzymes
synthesize lipids
- fatty acids, phospholipids, steroids, detoxify drugs
metabolize carbs
store Ca2+ = muscle contractions

golgi complex

processes and distributes product from the ER
produces polysaccarides
layers of flat membrane sacs
vessicles to and from the golgi
- more golgi = more secretion

lysosomes

membrane bound organelle that contains digestive enzymes

autophagy

digesting dysfunctional organelles

mitochondria

powerhouse of the cell
produces ATP - adenosine triphosphate
generates body heat

chloroplasts

captures suns energy

endosymbiosis meaning

inside-together-life

endosymbiosis in mitochondria and chloroplasts

both have 2 membranes
both have DNA - circular shape
both have their own ribosomes

microfillaments

cell shape, movement, muscle contraction

intermediate fillaments

cell shape, organelle anchoring

microtubules

chromosome and organelle movement
flagella and cilia

plants vs animals

plants lack lysosomes
plants have
-cell walls
-central vacuole
-chloroplasts

cell wall

provides structure and support

central vacuole

stores h2o, pigments, and waste

plant cell junctions

plasmodesmata
channels connecting plant cells
helps with diffusion of molecules in cytoplasm

animal cell junctions

gap junctions
similar to plasmodemata
found in heart and animal embryonic stage

tight conjunctions

leakproof sheet
line digestive tract

desmosomes

anchoring junctions
strong connection in stressed tissue
skin and heart muscle

cell membranes

boundary between cell interior and membrane
enables. internal regulation- char. of life
membranes are both flexible and stable

all cells have external plasma membrane

but eukaryotes have internal as well

membranes have a

phospholipid bilayer

hydrophillic head

react well with h2o in cell

hydrophobic tail

keep stability in the cell

cholesterol

helps keep membranes more fluid @ cool temps
less fluid @ warm temps

membranes are

selectively permeable

selective permeability is

when some substances can cross more easily than others

hydrophobic molec pass through

non-polar membranes

hydrophillic molec pass through

polar membranes

fluid mosaic model

integral membrane proteins

pass into or through hydrophobic region of the membrane

peripheral membrane proteins

attach to the outside of the membrane

membrane protein functions

transport enzymes, cell communication, physical attachment

glycoproteins made of

carb + protein

glycolipid and glycoprotein functions

used in cell identification
immunity (self vs non self)
embryonic cell sorting

passive transport

not requiring cellular energy

diffusion

passive transport
movement from high concentration to low concentration
all molec are in constant mostion
each molec moves independently from other molec

factors that influence diffusion rate

size of molecule/ membrane
the concentration gradient
- larger difference in gradient = faster
temperature
- warmer = faster
elec. or pressure gradients

facilitated diffusion

passive transport
movement aided by membrane proteins with a channel or carrier

what needs facilitated diffusion

larger molec, polar molec, charged molec

aquaporin

facilitated protein for H2O
needed bc water is polar

facilitated proteins have

specific shape for each substance
ex enzymes

osmosis

movement of free H2O molec from low solute concentration to high across a semi permeable membrane

isotonic

same concentration on each side
no net movement on each side of cell but flow in and out

hypotonic

lower concentration

hypertonic

higher concentration

cells ____ to maintain balance

osmoregulate

animal- lysed

exploded
hypotonic

animal- plasmolysed

shrivled
hypertonic

plant- flacid

limp
hypertonic

plant- turgid

firm
hypotonic
ideal for plant
doesnt explode due to cell wall

____ is ideal for animal cell

isotonic

active transport

cell expends energy for transport
up/ against concentration gradient
driven by ATP
Na+ and K+ pump
inside of cell has slight negative charge

cotransport

active transport
transport of diff solutes through common protein

exocytosis

exit cell

endocytosis

enter cell

endocytosis and exocytosis functions

fuse with plasma membrane to transport larger molec

phagocytosis

cell eating

pinocytosis

cell drinking

receptor-mediated endocytosis

is a process by which cells absorb metabolites, hormones, proteins – and in some cases viruses – by the inward budding of the plasma membrane

ligand

molec that binds to the receptor

size of plasma membrane

8nm

DNA

deoxyribonucleic acid

genome

complete set of an organisms genetic information

gene

a segment of DNA that is the coding for polypeptides
sequence of amino acids
proteins > 1 polypeptide

humans have ___ genes

25,000

there is a ____ copy of genes in almost every cell

full copy

what is DNA's monomer

nucleotides

DNA structure

5 carbon sugar
phosphate group
nitrogenous base = rungs

sugar phosphate backbone
held with H bonds

DNA has a _____ shape

double helix

Purines

adenine and guanine
2 ring structure

pyramidines

cytosine, thymine, uracil in RNA
1 ring structure

A pairs with

T

G pairs with

C/U

differences between DNA and RNA

DNA
- double strand
- deoxyribose = H, no oxygen
- thymine
RNA
- single strand
- ribose = OH
- uracil

deoxyribose

5 carbon sugar
1' 2' 3' 4' 5'
1' to nitrogenous base
5' to phosphate group
3' to next nucleotide phosphate

there are ____ bonds within a nucleotide

covalent

there are ____ bonds between nitrogenous bases

hydrogen

what is semiconservative replication

when the parent strand is conserved and acts as a template for the daughter strand

how many origins of replication do prokaryotes have

one

what shape are prokaryotes DNA

circular

how many origins of replication are there for eukaryotes

multiple

what shape is a eukaryotes DNA

linear

helicase function

unwinds DNA