bio1140 midterm 1

7 properties of life

Growth and development, Reproduction, Regulation and homeostasis, Response to stimuli, Energy and metabolism, Cellular organisation, Heredity and evolution

importance of carbon

bond to four groups (polymerisation), amino acid chains

importance of oxygen

needed for amino acid groups, cellular respiration \-- reacts with glucose

importance of hydrogen

determines the saturation of carbon chains, hydrogen bonding

importance of nitrogen

forms amine groups on carbon chains

cyclic dna

replication

cyclic rna

ribosomal activities

dna to rna

transcription

rna to dna

reversal

rna to protein

translation

advantages to multicellularity

increased SA for diffusion, longer lifespan, specialisation, protection, feeding, locomotion

light microscopy

magnified via refraction

TEM \-- transmission electron microscope

excite the electrons, internal structures of an organism, thin slices that are hard

SEM \-- scanning electron microscope

electrons scan the surface coated in gold and are liberated \-- converts to electrical signal for imaging

fluorescence microscope

marked with different fluorescent proteins, excited at specific wavelengths to see different proteins

formula of a sphere volume

4/3πr3

formula of a sphere surface area

4pir^2

microvilli

small extensions of a cell wall to increase SA and diffusion rates

prokaryotes or eukaryotes first?

prokaryotes

how did a prokaryote become a eukaryote

the eukaryote ate a prokaryote and that prokaryote became an organelle

embosymbiont organelle

double membrane

composition of plasma membrane

bilayer of lipids, with a hydrophilic head and hydrophobic tail

nucleoid

non-membrane bounded, circular chromosome is concentrated

nucleus

nucleolus, linear chromosomes made of chromatin

what is chromatin made of

DNA and histone

what is the cell wall of a prokaryote made of?

peptidoglycan layers

gram positive bacteria

thick outside, purple

gram negative bacteria

thin, sandwiched between two bilayers of phospholipids; pink

reproduction of prokaryotes

asexual, binary fission

locomotion of bacteria

flagellum made of flagellin; inserted in plasma membrane

how many RNA synthesizing enzymes in a bacteria?

one RNA synthesizing enzyme

what does the cytoplasm in eukaryotes contain

cytosol, organelles, inclusions

plant cell wall composition

cellulose

animal cell wall composition

ECM: glycoproteins, polysaccharides, collagen in proteoglycan

what is fibronectin

attaches ECM and integrins

reproduction of eukaryotes

sexual; mitosis, microtubule spindles

flagellum of eukaryotes

projects from cytoskeleton, made of microtubules

how many RNA synthesizing proteins are in eukaryotes

3 RNA synthesizing proteins

function of cytoskeleton

microfilaments, microtubules; networking of the cell

what happens to rRNA synthesis (ribosomal ribonucleic acid)

subunits leave nucleus via pores and become ribosomes

what is done with mRNA

synthesized in nucleus with genetic info needed to make proteins in cytoplasm

endoplasmic reticulum

continuous with nuclear envelope

rough ER

has ribosomes; makes or sends proteins via transport vesicles that bud off

smooth ER

enzymes for metabolisms; synthesis for phospho/lipids, steroids, cholesterol, carbohydrates, detoxifications, calcium storage after muscle contraction (sarcoplasmic reticulum)

golgi apparatus

cis receives, trans transports; posttranslational modifications (phosphorylation, glycosylation, acetylation

lysosomes

very acidic vesicles that contain hydrolytic enzymes for digestion \-- convert to simple sugars or amino acids \-- released into cytoplasm

peroxisome

removes hydrogen from substrates (H2O2), breaks down fatty acids into smaller molecules, oxidizes OH; H2O2 is then converted to H2O before leaving the organelle

glyoxisome

for seedlings to grow via breakdown of stored fatty acids \-- growth before photosynthesis

vacuole

plants! semi-permeable membranous sac that stores nutritious and poisonous molecules, lytic enzymes, pigments, water, ions; stores/produces molecules for genetic engineering

tendrils

climbing stems

turgor pressure

hydrostatic pressure of a vacule on cell wall

aerobic respiration chemical formula

C6H12O6 + 6O2 -\> 6CO2 + 6H2O

where is energy derived from?

the energy between the bonds of atoms (carbon or phosphate groups) \-- electrons are released

infoldings of mitochondria are called...?

cristae

does mitochondria have its own DNA?

yes

does chloroplast have its own DNA?

yes

what is the purpose of cristae in mitochondria?

increased surface area

what is a thylakoid?

disc; contains photosynthetic pigments that capture sun

what is chlorophyll

pigment that captures sun

why is chlorophyll green?

it reflects green wavelengths of light

stroma

fluid containing chloroplast DNA, ribosomes, enzymes \-- space between thylakoids

granum

stack of thylakoids

stroma lamellae

bridge that connects the thylakoids

chromoplasts are found in what kind of plant?

fruit and flower pigmentation

amyloplasts are found where

roots and tuber

what are microtubules made of?

thick, hollow rod made of tubulin proteins

microtubules and collagen

produces it in ECM; vesicles and enzymes travel on them

what end of a microtubule is connected to the centrosome?

negative end

what end of a microtubule can grow/shrink?

positive end

catastrophe of a microtubule

shrinking

rescue of a microtubule

growing

kinesin

walking guy; carries cargo to plus end

dyenin

cherry guy walks cargo to negative end

how do transport proteins move?

ATP powered

why are microtubes related to mitosis?

centrosome projects MTs and it pulls chromosomes appart

composition of the centriole of a centrosome

9+0 arrangement

composition of an axoneme

9+2 arrangement

purpose of axoneme

flagella and cilia; locomotion or SA

how does flagella/cilia move?

dynein slides the microtubules to flap the appendage

what is gdp tubulin made of

alpha and beta tubulin

what does gtp tubulin do

it forms a gtp cap when polymerized \-- gdp: the gtp loses a phosphate group when polymerizing

what are microfilaments made of?

double chain of actin filaments that act alone or in muscle contraction

purpose of microfilaments when it works on its own?

resists compression, maintains shape of cell,

what is myosin?

it is a protein (thick filament) that is a part of muscle contraction

steps in muscle contraction?

1. myosin head is bound to atp and is low
2. adp and phosphate bind to the myosin head
3. calcium binds to troponin to pull the tropomyosin from closed to open
4. myosin head attaches: myosin cross-bridge
5. adp and phosphate is released, head pulls the thin filament to the centre of the sarcomere \-- Z lines are closer
6. atp binds again

role of intermediate filaments

mechanical support of cell and nuclear lamina against physical stress

how permanent are intermediate filaments

more permanent than microtubules \-- less change of catastrophizing.

plasmodesmata (plants)

neighbouring cells that have small channels where substances can travel through

tight junctions

impermeable,; made of occludin and claudin that bind from neighbouring cells \-- prevents leakage in epithelium

desmosomes

semidesmosomes from neighbouring cells that bind to each other via transmembrane proteins \-- found especially in tissues that stretch

gap junctions

the animal cell version of plasmodesmata; 6 proteins in a flower shape that open to let ions and small molecules travel intercellularly.

what is a lipid

large, nonpolar molecule that is hydrophobic

what is a fatty acid

hydrocarbon chain with a carboxyl group at one end

what is a saturated fat

(ex. butter) solid at room temperature with a carboxylic acid end (C\=O and CHO_)

what environment are saturated fats found

in animals that live in warm environments

what does a saturated fat mean in terms of bonding

alkane, the carbons have the max amount of hydrogens it can have.

what is an unsaturated fat

(ex. oil) is liquid at room temperature

what environment are unsaturated fats found

in colder climates

what is an unsaturated fat in terms of bonding

carbon chain with double bounds at every kink

what is the importance of double bonds in an unsaturated fat

the kinks push on each other, allowing the organism to move; lower melting points