Final Unit 3 Biology 11 Cell Structure/ Nervous System

Microscope parts and functions

Ocular lens Lens you look through; usually magnifies 10×.

Objective lens Lens that provides most of the magnification.

Stage Platform that holds the slide.

Stage clips Hold the slide in place.

Diaphragm Controls the amount of light passing through the specimen.

Light source Provides light for viewing the specimen.

Coarse adjustment knob Large knob used for rough focusing on low power.

Fine adjustment knob Small knob used for sharp focusing, especially on high power.

Arm Supports the upper part of the microscope.

Base Bottom support of the microscope.

Cell stains

Chemicals used to make cells and structures easier to see under a microscope.

Cell theory

All living things are made of cells, cells are the basic unit of life, and cells come from existing cells.

Prokaryote

Simple cell without a nucleus or membrane-bound organelles.

Bacteria

Single-celled prokaryotes found in many environments.

Archaea

Single-celled prokaryotes often found in extreme environments.

Eukaryotic cell types

Cells with a nucleus and membrane-bound organelles.

Protists

Diverse group of mostly single-celled eukaryotes.

Plant cell

Eukaryotic cell with a cell wall, chloroplasts, and a large central vacuole.

Animal cell

Eukaryotic cell without a cell wall or chloroplasts.

Fungi

Eukaryotic organisms that absorb nutrients from their surroundings.

Fluid-Mosaic Model

Model describing the cell membrane as a flexible layer with proteins embedded in lipids.

Cell membrane

Thin barrier that controls what enters and leaves the cell.

Lipid bilayer

Double layer of phospholipids that makes up the cell membrane.

Selectively permeable

Allows some substances to pass while blocking others.

Mitochondria

Organelles that produce ATP energy through cellular respiration.

Lysosomes

Organelles containing enzymes that break down waste and old cell parts.

Nucleus

Organelle that stores DNA and controls cell activities.

Golgi apparatus

Organelle that modifies, packages, and ships proteins.

Vesicles

Small membrane sacs used for transport and storage.

Ribosomes

Structures that make proteins.

Cell wall

Rigid outer layer that supports and protects some cells.

Centriole

Structure that helps organize spindle fibers during cell division.

Endoplasmic reticulum

Membrane network involved in protein and lipid production.

Active transport

Movement of substances across a membrane using energy.

Passive transport

Movement of substances across a membrane without energy.

Concentration gradient

Difference in concentration between two areas.

Sodium-potassium pump

Protein that uses ATP to move sodium out and potassium into the cell.

Diffusion

Movement of molecules from high concentration to low concentration.

Facilitated diffusion

Movement of molecules through transport proteins without energy.

Endocytosis

Process by which a cell takes materials in using vesicles.

Exocytosis

Process by which a cell releases materials using vesicles.

Osmosis

Diffusion of water across a selectively permeable membrane.

Hypertonic

Solution with a higher solute concentration than the cell, causing water to leave the cell.

Hypotonic

Solution with a lower solute concentration than the cell, causing water to enter the cell.

Isotonic

Solution with equal solute concentration to the cell, causing no net movement of water.

Aquaporins

Channel proteins that allow water to move across membranes.

Neuron

Nerve cell that transmits signals throughout the body.

Motor Neuron

Neuron that carries signals from the brain and spinal cord to muscles and glands.

Sensory Neuron

Neuron that carries signals from sensory organs to the brain and spinal cord.

Brain

Organ that processes information and controls body functions.

Spinal Cord

Bundle of nerves that connects the brain to the rest of the body and relays signals.