A and P Lab 2

Cells vary by

Type, structure, and function

Plasma membrane

Outside barrier of the cell

Cytoplasm

Includes cytosol and all the organelles and structures in it

Cytosol

Fluid component of the cytoplasm

Nucleus

Contains the cell’s DNA and controls cell activities

Phospholipid bilayer (plasma membrane)

Made up of phospholipid molecules. The heads are hydrophilic and face outwards, while the tails are hydrophobic and face inwards

Proteins in and around the lipid bilayer form ion channels, carry substances through the membrane, act as markers or receptors, and facilitate other cellular functions

Semi-permeable

Passive Transport

Osmosis or diffusion, these don’t require the cell to use any energy

Active Transport

Move molecules from low to high concentration. It uses specialized channels or carriers in the cell membrane. This process expends energy

Hypertonic Solution

Greater concentration of water inside the cell than outside the cell. Water flows out and the cell shrinks

Isotonic Solution

Balance of water inside and outside of cell is equal

Hypotonic Solution

Greater concentration of water outside the cell than inside. The cell swells and may burst

Cytoskeleton

Consists of proteins called microfilaments and microtubules that support the cell

Centrosome

Contains centrioles and pericentriolar material that are essential for cell division

Endoplasmic Reticulum

A folded membrane network that synthesizes proteins and other substances. Rough ER contains ribosomes, but smooth ER doesn’t

Golgi Complex

Proteins produced in the ER are processed in a set of membrane sacs known as the Golgi complex before being released. It packages

Lysosomes

Capsules inside the cell that contain digestive enzymes. Their function is to break down substances consumed by the cell or to recycle waste

Peroxisomes

Process and neutralize toxins, metabolize long chain fatty acids, and contribute to energy production

Nucleus

Largest organelle and it contains the cells genetic information encoded in the molecules of DNA

Mitochondria

Use oxygen taken in by the cell to produce ATP, the molecule that cells use as fuel for energy

Ribosomes

Produced by the nucleolus, these organelles synthesize proteins

Transcription

The double-helix DNA molecule is unzipped, and a messenger RNA (mRNA) molecule is created from the DNA template

Translation

Formation of a linear chain of amino acids (a protein), using the transcribed information provided by an mRNA strand. The mRNA template is “translated” to synthesize a protein within the ribosome

Interphase

Cells perform their normal functions and prepare for division. During this period, cells grow and create copies of their organelles, replicate their DNA, and synthesize proteins

G1

The growth stage of interphase

S

The stage of interphase where DNA replicates

G2

The stage of interphase when the cell prepares for division

Mitosis

After interphase

The cell phase in which the nucleus divides

Two identical offspring

Diploid, 46 chromosomes

Prophase

The first stage of mitosis; the nuclear membrane disappears

Metaphase

The second stage of mitosis; chromosomes align in the middle of the cell

Anaphase

The third phase of mitosis; sister chromatids move to opposite ends of the cell

Telophase

The fourth phase of mitosis; the nuclear membrane and nucleolus reappear

Cytokinesis

The division of the cell cytoplasm. Begins near end of mitosis and finishes after mitosis

Meiosis

After interphase

Cell division that produces sex cells

4 genetically different offspring

Haploid, 23 chromosomes