EOC REVIEW

Cell Processes Day 3

Cell Theory

  1. All cells come from pre existing cells
  2. Cells are the basic unit of structure and function
  3. All living things are made of cells

Cell to Cell Communication

•Chemical Signals (hormones) can be sent from one cell to another

•Receptor proteins on the plasma membrane receive the signal

Review Questions

  1. What are the levels of cell organization?

CellTissueOrganOrgan SystemIndividual Organism

  1. What do eukaryotes have that prokaryotes don’t have?

Eukaryotes contain a nucleus and membrane bound organelles

Organelles-compartment for carrying out a specific job/reaction

•Chloroplast: Photosynthesis, plant cell only

•Mitochondria: “powerhouse” of the cell, produces energy in ATP form, cellular respiration

•Ribosomes: protein synthesis, in prokaryotes and eukaryotes. A protein is a polymer made of a series of amino acid monomers. Examples of protein are some hormones and enzymes

•Lysosome- digest waste/ food material

•Vacuoles: storage of materials. Plants have one large vacuole

•Nucleus: control center, contains DNA/chromosomes

•Nucleolus: makes ribosomes

•Endoplasmic Reticulum-

•Rough – transports protein

•Smooth – synthesizes lipids and membranes

Review Questions

  1. Name one organelle a plant cell has that an animal cell doesn’t.

Chloroplast, cell wall, large vacuole

  1. Name one organelle an animal cell has that a plant cell doesn’t.

Centrioles

  1. Name one organelle an animal cell and plant cell have in common.

Cell membrane, mitochondria, ER, golgi apparatus…

Plasma Membrane AKA Cell Membrane

•Surrounds the cell

•Regulates what enters and leaves the cell

•Helps maintain homeostasis

•Made of phospholipids with embedded proteins

Osmosis & Diffusion- Passive Transport

•Diffusion: solutes move from high to low concentration

•Osmosis: diffusion of water from high to low water concentrations through a semi permeable membrane

Hypotonic – water enters cell

Hypertonic – water exits cell

Isotonic – equal movement of water in and out of cell

•Does not require energy: Passive Transport

•Ex: cell is salt water shrivels & cell in fresh water swells

•Ex: Turgor pressure in plants- wilted plants do not have enough pressure

•Ex: regulating the amount of water lost during transpiration due to opening and closing in stoma and guard cell.

Facilitated Diffusion

•Movement of a substance down its concentration through a transport protein channel

Review Questions

  1. What is passive transport?

Movement of molecules from a high to low concentration: Does not require energy.

  1. What are the examples of passive transport?

Diffusion and Osmosis

  1. What does semi permeable mean?

Some (semi) particles can enter/leave and others cannot

Active Transport

•Particles move against the concentration gradient from low to high concentration, which REQUIRES ENERGY (ATP)

  • Endocytosis: process by which cells take in material
  • Phagocytosis: the process of a cell engulfing solid particles
  • Pinocytosis: cells engulf liquid particles
  • Exocytosis
  • Energy process which a cell releases contents out of the cell membrane

Review Questions:

Fill in this chart. Also give the letter or number of the part as seen in the diagrams below.

Cell Part and Letter / Structure Description / Function
Nucleus / Contains cells heredity information and controls growth & reproduction. / Control center of the cell
Plasma Membrane / Also known as cell membrane. Protects the interior of the cell. / Controls the movement of substances in and out of the cell.
Cell wall / Made up of cellulose. / A tough outside layer surrounding a plant cell.
Mitochondria / Provides the cell with energy. / “Powerhouse” of the cell.
Vacuoles / Plants have one large vacuole. Animals have one or more small vacuoles. / Storage of materials.
Chloroplasts / Only in plant cells. / Carry out photosynthesis.
Ribosomes / Synthesizes (makes) proteins. Protein production.

Comparison of active and passive transport

PASSIVE TRANPORT / ACTIVE TRANSPORT
Requires energy? / Does NOT require energy / Requires Energy (ATP)
Low to high concentration or high to low concentration? / High to Low / Low to High
Examples / Diffusion/Osmosis / Endocytosis & Exocytosis

1. Which cell is the plant cell (left or right)? LEFT

2. Which structures are found only in the plant cell?

Cell wall, chloroplast, large vacuole

3. Which structures are found only in the animal cell?

Centrioles