Parts of a Cell Flashcards
Mitochandria
Organelles responsible for making ATP (energy)
Vacuole
Small organelle used to transfer materials within and out of the cell.
Nucleus
Contains all the genetic information (DNA).
Where DNA replication and transcription occur. Afterward mRNA is transported out of the nucleus.
Endoplasmic Reticulum
Used for translation of mRNA into proteins.
- Rough ER has ribosomes attached to transform RNA into protein
- Smooth ER associated with production of fats and steroid hormones
Ribosomes
small two-protein unit that reads mRNA & creates an amino acid
Golgi Apparatus
Collects, packages, & distributes the proteins produced by ribosomes
Chloroplasts
ONLY FOUND IN PLANT CELLS, where the reactions of photosynthesis take place.
Cell Membrane
-A semi-permiable membrane that surrounds the cells and controls what enters & leaves.
-Composed of Phospholipids
What is the difference between plant cells & animal cells?
Plant cells have a cell wall that doesn’t allow molecules to flow in or out.
Phospholipids
-Consist of an alkane tail & phospho-group head
1) Alkane Tail= hydrophobic
2) Phospho-group Head= hydrophilic
- Both of these molecules arrange to form the phospholipid bilayer which controls the import and export of substances into the cell.
Active Transport
- Uses ATP to move a molecule against the concentration gradient (from low concentration to high) or used to import/export a bulky molecule (sugar or a protein) across cell membrane.
Passive Transport
- Does not require ATP & allows molecules such as water passively diffuse across cell membrane.
EX: Facilitated Diffusion or Osmosis
Osmosis
-The process by which water enters or exits a cell.
Tonicity
-The concentration of solutes in a cell.
- Chemiosmotic Potential attempts to make tonicity equal across the membrane (inside & outside cell)
- EX: if higher tonicity inside the cell, water will enter the cell. If higher tonicity outside the cell, water will leave the cell.
3 Types of Tonicity
1) Isotonic- same concentration of solutes inside & outside the cell (no water transport)
2) Hypertonic- concentration of solutes outside the cell is higher so water will leave the cell (what happens if a cell is placed in a salty solution)
3) Hypotonic- concentration of solutes inside the cell is high so water will enter the cell (cell will swell becoming turgid)
What does salting meat do?
Creates a hypertonic environment that dehydrates microbes such as disease- causing bacteria to protect meat from infection (bacterial cells lose so much water that they can no longer function).
Cell Communication
1) Cycle AMP & Neurotransmitters are used for signaling cells close together.
2) Hormones are used for long-range or endocrine signaling (EX: production of insulin by the pancreas because it is only produced by cells in the pancreas but affects nearly all other cells in the body (by binding to receptors on a cell & telling it to take in more glucose).
The Cell Cycle (Go Sally Go, Make Children!)
1) G1: Growth Phase 1
2) S phase: DNA Synthesis
3) G2: Growth Phase 2
4) Mitosis
5) Cytokinesis
Phases 1-3 = Interphase (80-90% of total time in cell)*
What is Mitosis & it’s 5 substages? (IPPMAT, I Perfectly Passed My Math Test)
1) Prophase- DNA winds into chromatin & each pair of chromosomes are joined.
2) Prometaphase- nuclear membrane dissolves allowing chromosomes to attach to microtubules (which are linked to centrioles)
3) Metaphase- centrioles go to opposite sides of the cell, chromosomes align in the middle.
4) Anaphase- chromosomes move to separate sides of the cell & the cell structure starts to pull apart.
5) Telophase & Cytokinesis- Cell membrane splits & two new daughter cells are formed.
What is Meiosis?
Cellular division that creates gamets (sex cells)
