Topic 3 Cells

1.6.1

3.2

3.2

Cell membrane Boundary Metabolic reactions Signal transduction

Characteristics: Extremely thin Flexible Selectively permeable

“Receptor” “transport” 3.3.1

2. Cytoplasm Diffusion medium Dissolved materials for rxns Site of rxns

Endoplasmic reticulum Cisternae Intracellular transport Site for protein synthesis & others Ribosomes Protein & RNA Found… Links a.a.

Makes/stores… Has ribosomes Protein synthesis Lipids Hormones glycogen Smooth ER Rough ER Makes/stores… Lipids Hormones glycogen Has ribosomes Protein synthesis

Renews/modifies the cell membrane Modifies/packages/delivers proteins Golgi apparatus Renews/modifies the cell membrane Modifies/packages/delivers proteins May or may not be released 3.6.1

Tiny sacs with dig. enzymes Lysosomes Tiny sacs with dig. enzymes Break down/recycle: Organic molecules Damaged organelles Pathogens Cholesterol & toxins Isolates reactions 3.6.2

Mitochondria

3.1

Centrosome

Involved in cell division 9 triplet groups of microtubules Cytoskeleton factory Involved in cell division 9 triplet groups of microtubules 3.4.3

Cilia & flagella

Produce undulating motion 9 pairs of microtubules Produce undulating motion 3.4(4,5)

Cytoskeleton

Microfilaments Actin rods Alters shape Framework Microtubules Tubulin Rigid From centrioles Tract 3.4.1

Inclusions can be melanin, lipids, etc

3. Nucleus Control center Stores DNA 3.9.1

Chromatin

CELL TRANSPORT

Diffusion- movement of solutes from high to low concentration Movement into & out of the cell. Diffusion- movement of solutes from high to low concentration Requires no energy 3.14.1

3.13

Osmosis Osmolarity Osmotic flow

Tonicity 3.15.2

3.16.1

Not gradient dependent Requires ATP “Ion pumps.” 3.16.2

Endo/Exocytosis Vesicular transpot Uses ATP Large substances 1.Receptor-mediated endocytosis Receives specific materials 3.17.1

2. Pinocytosis Not selective

3. Phagocytosis For large/solid substances Phagocytes & macrophages Clean up/defense 3.17.3

Cell cycle 3.18.2

Interphase Somatic cells spend most time Duplication Many check points Divided into phases

3.19.1

3.20(1-6)

Cell differentiation 3.1.2

Control of Cell Division Telomeres Cell size Kinase & cyclins Growth hormones Space availability

3.21(1-4)

Cancer Unchecked growth Does not respond to factors Likely with high turn over Loss of function Benign vs malignant

Nucleic acids & protein synthesis 3.9.2

Two chains of nucleotides Ladder Nucleic acids & protein synthesis Gene Enough DNA… Genome All cellular DNA Two chains of nucleotides Ladder Backbone Rungs 2.20.3

Triplet = 3 base pairs = codon Genetic code Sequence of base pairs Triplet = 3 base pairs = codon 3.11.1

translation transcription 3.10.2

Transcription RNA polymerase mRNA & codon Uracil Translation tRNA matches mRNA 3.10.3+

transcription 3.11 +

translation 3.12+

DNA Replication Location… Preparing… During… Uses… 3.19.2

Changes in genetic information: Mutation B.p. replaced B.p. added B.p. deleted Inversion Transfer of DNA Errors can be corrected Repair enzymes or masked Multiple codes for an amino acids reduce changes.