BIOS 1030 EXAM 1

Metabolism

chemical reactions that transform molecules and energy to maintain life

Homeostasis

maintaining constant internal environment within cells and body as a whole

Domain: Bacteria

single cells, no nucleus

Domain: Archaea

primitive single cells, no nucleus, live in extreme conditions

Domain: Eukarya

Protista (protozoans and algae), Animalia, fungi, Plantae

kingdom

animalilia

phylum

chordata (backbones)

class

mammalia

order

primates

family

homoinidae

genus

homo (us but alive)

species

sapiens

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Animalia, chordata, mammalia, primates, hominidae, homo, sapiens

4 characteristics of being human

bipedalism, opposable thumbs, large brains, complex language

Elements in a living organism

H, C, N, O, P

Ionic bonds

atoms gain or lose electrons and opposite charges attract

Covalent bonds

atoms share electrons in order to fill outer electron shell

Hydrogen bonds (ex. 2 water molecules)

Partial charges interact

What types of molecules dissolve in water? 

Polar (partial charge), charged

Why do they dissolve in water?

charges interact with charge in water molecules

What does not dissolve in water?

Uncharged molecules like lipids

Why can they not dissolve?

cannot interact with water molecules

pH measures…

acidity or concentration of H+

Acid

less is more, releases H+

Bases

more is less, accepts H+

Carbon

makes 4 bonds with other atoms, more diverse structures, double bonds make molecules less flexible

Proteins

chains of molecules call amino acids

Lipids

Fats and oils, soluble in organic solvents and insoluble in polar solvents,

Carbohydrates

either single sugar molecules or chains of sugar

DNA

Carbohydrate uses

energy- glucose and other simple sugars broken down for energy, complex carbohydrates like glycogen store energy

saturated fatty acids

no double bonds, straight

unsaturated fatty acids

have double bonds, bent

lipid uses

fats store energy, phospholipids make membranes

importance of sequence in amino acids

determines shape and function

enzymes

acerbate biological reactions, can work over and over again

substrate

molecule enzymes works on

product

what it makes the substrate into

Nucleic Acid

chains of nucleotides

A to

T

C to

G

RNA

single stranded, has sugar ribose, USES U INSTEAD OF T

Transcription

making an RNA copy of the gene called the messenger RNA (mRNA)

Translation

making a protein using the information in the mRNA

ATP

energy currency, used by cells to get energy to work

Where in the ATP molecule is energy stored and how is it accessed by the cell?

stored in bonds between phosphates, cut off last phosphate to release and use energy

Eukaryotic

DNA within nucleus, have membrane-bound organelles, 10-100 um

prokaryotic

DNA is NOT enclosed in a nucleus, much smaller (1-2um), no organelles

phospholipids

form a bilayer of the membrane

cholesterol

affects flexibility of membrane

proteins (membrane)

control passage of molecules in and out of cell, receive information to send to other cells

Carbohydrates (membrane)

attached to some proteins (glycoproteins)

Passive transport

does not require energy to move substances across cell membranes.

What type of molecules can pass through membrane?

small,uncharged molecules like O2 or CO2

What type of molecules cannot pass through the membrane?

charged molecules like H+, larger molecules

Active transport

Movement from low toward high concentration, energy from ATP required

What are exocytosis and endocytosis?

Transport out of or into cells using vesicles forming or merging with the membrane (requires ATP)

signal transduction

information crossing the plasma membrane

a protein in the plasma membrane

signaling molecule binds to receptor

like a switch - on when signaling molecule binds

receptor becomes active

receptor acts as

an enzyme to create a product inside cell which carries the signal into a cell

Nucleus

DNA stored here, transcription happens here to make RNA

Endoplasmic reticulum

Rough ER- protein synthesis, Smooth ER- lipid synthesis

Golgi apparatus

protein and lipid processing and shipping

Lysosome

Macromolecule destruction and recycling

Cytoskeleton

protein fibers- support cell, give it shape and strength

Mitochondria

energy production

cellular respiration

breakdown food molecules to get energy in usable form - ATP

IN (cellular respiration)

glucose and O2

OUT (cellular respiration)

CO2 and ATP

Glycolysis

occurs in cytoplasm, glucose is split in half

Preparatory step

occurs in mitochondria, pyruvate made into acetyl-CoA and energy captured as electron carries

Glycolysis (IN)

glucose, 2 ATP

Glycolysis (OUT)

pyruvate, 4 ATP (2 net gain), electron carriers

Preparatory step (IN)

pyruvate

Preparatory step

acetyl-CoA, CO2, electron carries

Citric Acid Cycle

occurs in mitochondria, chemical cycle, energy used to make electron carriers and ATP

Citric Acid Cycle (IN)

Acetyl-CoA

Citric Acid Cycle (OUT)

CO2, ATP, electron carriers and ATP

Electron Transport Chain

occurs along inner mitochondrial membrane

Electron Transport Chain (IN)

electrons from electron carriers, O2

Electron Transport Chain (OUT)

lots of ATP

Electron Transport Chain (What happens)

electron carriers give electron to chain as electrons pass, energy pumped to H+ into intermembrane space, at the end of the chain electron give to O2, H+ go down in concretion gradient through ATP synthase

No oxygen in cellular respiration

all steps after glycoside are blocked, get small amount of ATP, pyruvate made into latin acid

M (1st phase of the cell cycle)

mitosis (nuclear division), cytokinesis (cell division)

G1 (second phase of cell cycle)

cell growth, preparation for DNA synthesis

S (third phase of cell cycle)

DNA synthesis (replication)

G2 (fourth phase of cell cycle)

preparing for mitosis

G0 (final phase of cell cycle)

exit from cell cycle

How DNA is copied

double helix unwinds, DNA polymerase adds new nucleotides one at a time, nucleotides are complementary to parent strands (AT,CG)

homologous chromosomes

cells have 2 copies of each chromosome (1 mom, 1 dad), both copied in S phase (sister chromatids)

Prophase (mitosis)

chromosomes condense, spindle forms, nuclear envelope dissolve, chromosome attach to spindle

Metaphase (Mitosis)

chromosomes line up at center of cell

Anaphase (mitosis)

sister chromatids separate and move toward opposite sides of cell

Telophase (mitosis)

chromosomes reach end of spindle, chromosomes decondense, new nuclear enevoples

Cytokinesis

cell divides to create 2 new daughter cells

Meiosis 1

homologous chromosomes line up side by side metaphase, crossing over exchanges DNA between non-sister chromatids, entire chromosomes (with both sister chromatids) goes to daughter cell

Meiosis 2

works like mitosis (sister chromatids separates)

mitosis results

4 cells (with only one copy of each chromosome), each chromosome is mom or dad’s mixture

transcription

DNA unwinds at the gene to be expressed, RNA polymerase copies by adding nucleotides (A-U)