Cell Structure, Metabolism, Respiration, DNA, and Cell Division Flashcards

Comprehensive vocabulary flashcards covering cell structure, cell metabolism, cellular respiration, DNA replication, gene expression/regulation, and mitosis/meiosis based directly on the lecture study guide.

Organelle

A specialized structure within a cell performing a specific function.

Prokaryote

Cell without a nucleus or membrane-bound organelles (e.g., bacteria).

Eukaryote

Cell with a nucleus and membrane-bound organelles (e.g., plants, animals).

Nucleus

Contains DNA, coordinates cell activities; double membraned.

Mitochondria

Energy (ATP) production through respiration; double membraned.

Chloroplast (plants/algae)

Photosynthesis; double membraned.

Endoplasmic Reticulum (ER)

Protein (rough ER) and lipid (smooth ER) synthesis.

Golgi Apparatus

Packages, modifies, and ships products.

Lysosome

• Digests substances

• single membrane (m.b.o)

• suicide bags

Peroxisome

Breaks down fats/toxins; single membrane.

Ribosome

Protein synthesis (not membrane bound).

Microtubules

• Largest & thickest cytoskeleton filaments

• hollow rods for cell shape & transport

• made of tublin

Intermediate filaments

Cytoskeleton filaments that provide structural support.

Microfilaments (actin)

• Cytoskeleton filaments involved in movement and shape

• works w/ myosin to contract

Enzyme

Protein acting as a catalyst, speeding reactions.

ATP (Adenosine Triphosphate)

Cell's energy molecule.

Activation Energy

Minimum energy to start a reaction.

Catalyst

Lowers activation energy, speeds reactions.

Protease

Enzyme breaking proteins.

1st Law of Thermodynamics

Energy is neither created nor destroyed.

2nd Law of Thermodynamics

Energy conversions increase disorder (entropy); some energy lost as heat.

Endergonic

Reaction needing energy input.

Exergonic

Reaction releasing energy.

Substrate

Molecule enzyme acts on.

Active Site

Region where enzyme binds substrate.

Glycolysis

Breaks down glucose to pyruvate in cytoplasm, net gain 2 ATP.

Pyruvic Acid (Pyruvate)

End product of glycolysis.

NADH/FADH2

Electron carriers.

Kreb’s Cycle (Citric Acid Cycle)

Produces NADH, FADH2, ATP, CO2 in mitochondria.

ETC (Electron Transport Chain)

Uses electrons to build H+ gradient, making ATP.

Conversion to Acetyl CoA

Pyruvate → Acetyl CoA, enters Krebs.

Chemiosmosis

ATP synthesis via H+ gradient and ATP synthase.

G3P

3-carbon intermediate in glycolysis.

Helicase

Unwinds DNA.

DNA Polymerase

Builds new DNA strand.

Semi-conservative Replication

Each new DNA has an old and new strand.

Complementary Base Pairing

A-T, C-G.

Promoter

DNA region where transcription starts.

Exon

Coding region of gene.

Codon

3-base mRNA code for amino acids.

RNA Polymerase

Makes RNA from DNA.

Anticodon

3-base code on tRNA matching codon.

Cap & Tail

RNA modifications for stability/recognition.

Transcription

DNA → mRNA.

Translation

mRNA decoded to protein.

Point Mutation

Single-base change.

P Site/A Site (ribosome)

Sites where tRNAs bind during translation.

Insertion/Deletion Mutation

Adds or removes base(s), shifts reading frame (frameshift).

Intron

Non-coding, removed from mRNA.

Somatic Cells

Body (non-reproductive) cells.

Activator Protein

Turns gene ON.

Repressor Protein

Turns gene OFF.

Gene Regulation

Controlling gene expression.

Sexual Reproduction

Offspring from two parents; genetic variation.

Mitosis

Cell division for growth & repair; produces identical cells.

Meiosis

Cell division for gametes (eggs/sperm); halves chromosome number.

Cell Cycle

All phases of cell’s life (G1, S, G2, M).

Interphase

G1 (growth), S (DNA replication), G2 (prep).

Chromatin

DNA + proteins; loosely packed.

Chromosome

Condensed DNA.

Sister Chromatid

Identical DNA strands post-replication.

Centromere

Region joining sister chromatids.

Kinetochore

Protein on centromere for spindle attachment.

Spindle

Microtubule fibers that separate chromosomes.

Cleavage Furrow

Indentation in animal cells during cytokinesis.

Meiosis I/II

Division phases; I separates homologs, II separates sister chromatids.

1N/Haploid

Half chromosome set.

2N/Diploid

Full chromosome set.

Gametes

Egg/sperm; haploid cells.

Zygote

Fertilized egg; diploid.

Homologous Chromosomes

Same type, not identical.

Chiasmata/Crossing Over

Exchange parts between homologous chromosomes (genetic diversity).

Independent Assortment

Random segregation of chromosomes.

Interkinesis

Pause between meiosis I and II.

Spermatogenesis/Oogenesis

Sperm/egg formation.

Random Fertilization

Random sperm + egg meeting.

stages of interphase

The phases of the cell cycle during which the cell prepares for division, growth 1, synthesis, growth 2

nucleus vs nucleoid

The nucleus is a membrane-bound organelle found in eukaryotic cells that contains the cell's genetic material, while a nucleoid is a region in prokaryotic cells where DNA is located, not surrounded by a membrane.

synthesis

each chromosome now consists of 2 identical sister chromatids, which are held together at their centromere regions and DNA replication occurs during this phase.

G1

1st growth phase (normal cell business + doubling of organelles)

G2

2nd growth subphrase, making proteins for cell division

M phase

prophase, metaphase, anaphase, telophase

M phase 1

prophase

M phase 2

Metaphase

M phase 3

anaphase

M phase 4

Telophase

prophase 4 hallmarks

1. DNA condenses into chromosomes

2. nucleolus disappears

3. nuclear envelope disappears

4. spindle fibers

spindle fibers detail

each spindle fiber seeks to connect with a kinetochore on the outside of each pair of chromatids

metaphase

1. chromosomes line up in middle of cell

2. spindle fibers pushed then there

anaphase

1. proteins btwn chromosomes break down

2. chromatids separate - now chromosomes

3. chromosomes pulled to opposite sides of cell

telophase

prophase in reverse

• begins when chromosomes reach opposite poles

1. spindle fibers breaks down and disappears

2. nuclear envelope reforms

3. nucleolus reforms

4. DNA uncondenses

mitosis

first division, creates 2 identical daughter cells

meiosis

only one daughter cell goes through

aerobic cellular respiration

glycolysis, conversion to Acetyl CoA, Kreb’s cycle, ETC

anaerobic cellular respiration

glycolysis, fermentation

glycolysis (aerobic) where, net, end product

cytosol, 2 ATP & 2 NADH, 2 pyruvic acid

conversion to Acetyl CoA where, waste, net, end product

mitochondria, 2CO₂, 2NADH, 2 Acetyl CoA

Kreb’s cycle where, waste, net, end product

Mitochondria, 4CO₂, 2 ATP & 6NADH & 2 FADH₂, banked energy

Electron Transport Train where, cost, waste, net, end product

Mitochondria, ~2 ATP, 6H₂O, ~28 ATP, n/a

glycolysis (anaerobic) where, net, end product

cytosol, 2 ATP & 2 NADH, 2 pyruvate