MODULE 1: Cells as the basic of life Flashcards
what is an organelle
Tiny cellular structure that performs a specific function in a cell
List the main cell types for Prokaryotic
DNA is naked
DNA is circular
Usually no introns
No nucleus
No membrane-bound organelles
Single chromosomes
Smaller
Structurally simple
List the main cell types for Eukaryotic
DNA bound is protein
DNA is linear
Usually has introns
Has nucleus
Membrane-bound organelles
Chromosomes paired
Larger
Structurally complex
Light microscope
Light microscope
first type of microscope TOTAL MAGNIFICATION = objective lens x eyepiece
Electron microscope and explain SEM, TEM
uses electron beams instead of light
Scanning (SEM): scans the surface of the specimen
Transmission (TEM): produces images of internal organelles
Staining techniques
Dye allows for the staining E.g crystal violet stains the cell wall
lighting techniques
Phase contrast microscopy allows scientists to gain improved image quality of cells
function of a Cell membrane
Outer membrane that surrounds a cell, controls movement in and out of the cell.
function of a cell wall
Tough material surrounding the cell membrane in plant cells.
Supports and protects cells.
function of a nucleus
Directs cell activities
Separated from cytoplasm by nuclear membrane.
Contains genetic material DNA.
Function of a Cytoplasm
The material of the cell between the cell membrane and the nucleus.
Gel-like mixture
Surrounded by cell membrane
Contains hereditary material
Function of a Nucleus
Directs cell activities
Separated from cytoplasm by nuclear membrane.
Contains genetic material DNA.
Function of a Cell wall
Tough material surrounding the cell membrane in plant cells.
Supports and protects cells.
Function of a Cell membrane
Outer membrane that surrounds a cell, controls movement in and out of the cell.
Function of a Mitochrondria
The powerhouse of the cell.
Mitochondria combine oxygen and food to produce energy in the process of cellular respiration.
Controls level of water and other materials in the cell.
Function of a Chloroplast
Uses the energy in sunlight to turn water wand carbon dioxide into sugar and oxygen (a process called photosynthesis)
Usually found in plant cells.
Contains green, light-absorbing chlorophyll.
Function of a Vacuole
Membrane-bound sacs for storage, digestion, and waste removal.
Contains water solution.
Function of a Vacuole
Membrane-bound sacs for storage, digestion, and waste removal.
Contains water solution.
Larger in-plant cells.
Help plants maintain shape by storing water.
Function of a Ribosome
Cell structure that makes protein, for proper cell functioning including cell repair and metabolism.
Found floating within the cytoplasm or attached to the (rough) endoplasmic reticulum.
Function of a Lysosome
Contain digestive enzymes
Digest excess or worn out organelles, food particles and engulfed viruses or bacteria. It is known as the garbage disposal system of the cell.
Function of a Golgi apparatus
Membrane stacks with transport vesicles at the perimeter. They receive, sort, store and secrete materials
Function of a Endoplasmic Reticulum
Rough E.R:
Connect with the nuclear membrane and transport proteins throughout the cell, ribosomes are attached.
Smooth E.R:
Transports lipids and steroids, has no ribosomes
Passive Transport
without energy
Diffusion molecules spread from areas of high concentration to areas of low concentration along a concentration gradient
E.g oxygen enters the cells needed for cellular respiration from the capillaries
Facilitated diffusion movement of particles from high to low concentration through protein channels in the cell membrane
Passive Transport
without energy
Diffusion molecules spread from areas of high concentration to areas of low concentration along a concentration gradient
E.g oxygen enters the cells needed for cellular respiration from the capillaries
Facilitated diffusion movement of particles from high to low concentration through protein channels in the cell membrane
Osmosis the movement of water from high to low concentration across a semipermeable membrane until equilibrium is reacted
Active Transport
with energy
Endocytosis - cells take in substances from outside of the cell by engulfing them in a vesicle.
Phagocytosis - plasma membrane engulfs the solid material, forming a phagocytic vesicle
Pinocytosis - plasma membrane folds inwards to form a channel allowing dissolved substances to enter the cell when the channel is closed the liquid is encircled within a pinocytic vesicle.
Exocytosis is the release of cellular substances contained in cell vesicles by fusion of the vesicular membrane with the plasma membrane and subsequent release of the contents to the exterior of the cell.
What are Enzymes
Enzymes are organic catalysts, Enzymes are proteins made up of amino acids linked and folded to produce a three dimensional protein structure.
Catalyst Enzyme
substance that speeds up or brings about a chemical change without being used up or changed in the reaction.
Substrate Enzyme
the reactant on which an enzyme works.
Lock and Key model
the enzyme permits it to bind at a particular site to the substrate molecule (reactant). This causes a reaction to occur. The key (substrate) fitting the lock (enzyme).
Induced Fit model
when the active site slightly changes its shape to accommodate the substrate perfectly.
why does Temperature effect activity of Enzymes
why does Temperature effect activity of Enzymes
- Temperature
- PH
- Substrate concentration
why does Temperature effect activity of Enzymes
- Temperature
- PH
- Substrate concentration
why does Temperature effect activity of Enzymes
why does Substrate effect activity of Enzymes
why does PH effect activity of Enzymes
why does Substrate effect activity of Enzymes
- Enzyme concentration increased = rate of reaction increased
- Substrate concentration increased = enzyme concentration remains constant
why does PH effect activity of Enzymes
- Slight pH on either side of optimum pH = reversible changes
- Extreme pH variations = irreversible changes (denature)
why does Temperature effect activity of Enzymes
- Low temperature = activity of enzyme is low (vice versa)
- Increase in temperature = increase in kinetic energy
What is the Saturation Point
vmax or max velocity/rate
The Optimum Temperature
enzyme is most active
What is Denature
breaking of bonds (e.g hydrogen bonds) modifying the molecule structure
To much heat can cause a decrease because the enzymes become denatured
The substrate no longer has an active site with which it can bind so there is little to no activity
