Topic 3: Cellular Level of Organization Flashcards
Semipermeable, outer structure of cell
cell membrane
Composition of cell membrane
double-layer of phospholipids
Double-layer of phospholipids orientation
Phosphate head on outside - Hydrophilic
Lipid tails on inside - Hydrophobic
passive movement of substances from regions of highconcentration to regions of low concentration
Diffusion
passive movement of water molecules across asemi-permeable membrane
Osmosis
More selective/precise barrier than semi-permeable.
Selectively-Permeable
particle concentration outside the cell compared toinside the cell
Tonicity
equal concentrations outside vs. inside
Isotonic
Greater concentration outside vs inside
Hypertonic
Lower concentration outside vs inside
Hypotonic
forced movement of fluid across a membrane whosepores restrict the passage of solutes based on their size
Filtration
movement of a substance across thecell membrane by means of a protein carrier
carrier-mediated transport
Passive movement along a concentrated gradient
Facilitated diffusion
ATP-driven movement against aconcentration gradient
Active transport
Moving things in/out of cell
Vesicular transport
Transport something INTO the cell
Endocytosis
Vesicular movement of fluids
Pinocytosis
vesicular movement of extracellular substances (solids)
Phagocytosis
Receptors on the outside collect a specific molecule. Once enough receptors have the specific molecule, they pull into the cell to create a vesicle, travel thru the cell, release the molecules and make their way back to the membrane to collect more.
Receptor-mediated endocytosis
Transport of substances OUT of the cell (exit the cell)
Exocytosis
Everything inside the cell membrane besides the nucleus
Cytoplasm
Network of interconnected membranes, forming sacs and canals which transport/store materials within the cell
Endoplasmic Reticulum (ER)
Ribosomes where protein is synthesized
Rough ER
“ER” associated with lipid production (no ribosomes associated)
Smooth ER
Manufactures protein
Ribosomes
Handles protein particles that will be exported
Fixed ribosomes
Handles protein that get used within the cell
Free robisomes
Stack of interconnected flattened, membranous sacs, usually located near the cell nucleus
Golgi Apparatus
Processes protein molecules for secretion
Golgi apparatus
Membranous sacs/Storage & Transport compartments
Vesicles
Cell’s “power plant”/ Cite of ATP production
Mitochondria
Looks like vesical; Has Plasma membrane;
Has digestive chemicals; “janitorial dept of cell” - digests nutrients
Lysosomes
How do bodily cells differ?
size, shape, structure & function
Extensions of the cell’s surface, supported by microfilaments andmicrotubules. Microvilli
Cilia (shorter)
Flagella (longer)
Only human flagella
Sperm cell
Spherical, non-membranous mass located near cell nucleus, consisting of two rod-like centrioles (which are composed of
microtubules)
Participate in cell reproduction
Centrosomes
Home of the cell’s genetic material
Cell Nucleus
Small, dense body of protein and ribonucleic acid (RNA) in nucleus. Forms ribosomes.
Nucleolus
Uncondensed chromosomes (protein + deoxyribonucleic acid [DNA])
Chromatin
Somatic cell division
Mitosis - Interphase, Prophase, Metaphase, Anaphase, Telophase
interphase - normal cell function
G0 phase
interphase - cytoplasmic preparation for cell division
G1 phase
interphase - duplication of DNA and chromosomes
S phase
interphase - last minute preparations for cell division
G2 phase
Duplicated chromosomes coalesce out of the chromatin; two chromatids held together by a centromere
(phase of mitosis)
Prophase
Chromosomes line up individually along the cell’s equatorial plane
Metaphase
Chromatids separate from each other and migrate to opposite poles of the cell
Anaphase
Formation of new nuclear and cell membranes; cytokinesis
Telophase
Sex cell division, production of male and female gametes
Meiosis
S phase and DNA/chromosome duplicate (meiosis)
Interphase
REDUCTION of chromosomes from diploid to haploid
Meiosis I
Duplicated chromosomes coalesce out of the chromatin (meiosis I)
Prophase I
Chromosomes line up along the cell’s equatorial plane as HOMOLOGOUS pairs
Metaphase I
Chromosomes separate from their homologous partner and migrate to opposite poles
Anaphase I
Formation of new nuclear and cell membranes; cytokinesis
haploid number in each cell
Telophase I
Division of the sister chromatids
Meiosis II
Chromosomes coalesce out of the chromatin (meiosis II)
Prophase II
Chromosomes line up INDIVIDUALLY along the cell’s equatorial plane
(meiosis II)
Metaphase II
Chromatids separate from each other and migrate to opposite poles of the cell (meiosis II)
Anaphase II
Four daughter cells
Telophase II
Male sex cell formation resulting in four viable gametes (4 sperm cells)
Spermatogenesis
Female sex cell formation resulting in one viable gamete + two or three polar bodies due to uneven division of cytoplasm.
Oogenesis
Two stages of protein synthesis
TRANSCRIPTION: copying/making messenger RNA (mRNA) to be transferred to ribosomes.
TRANSLATION of mRNA at the ribosomes into a string of amino acids