IB Bio (A2.2, B2.1, B2.3)

cell membrane

cell membrane

A selectively permeable barrier that surrounds the cell, regulating the movement of substances in and out.

prokariotic cells

Cells without a nucleus or membrane-bound organelles, typically smaller than eukaryotic cells and found in bacteria and archaea.

eukariotic cells

Cells with a nucleus and membrane-bound organelles, typically larger than prokaryotic cells, found in organisms such as plants, animals, and fungi.

structures found in every cell:

cell membrane, cytoplasm, DNA/other genetic material

organelles

structures that preform a specific task within the cell (golgi apparatus, mitochondria, etc)

cell theory

everything is made of cells, cells are the basic unit of life, cells arise from other cells

ribosomes

small structures that synthesize proteins by translating messenger RNA

chloroplast

organelles that conduct photosynthesis in plant cells, converting light energy into chemical energy.

cell wall

provides extra support to the cell membrane, helps cells maintain their shape, ONLY IN PLANT CELLS

mitochondria

powerhouse of the cell, produces ATP (energy) through areobic resperationand contains its own DNA.

fluid mosaic model

current cell membrane model, hydeophillic, fatty acid tails, and hydrophobic, protein heads create a semi-permiable barrier for the cell

phospholipids

molecules that make up the cell membrane, consisting of a hydrophilic head and two hydrophobic tails, allowing for the formation of a bilayer.

sterol

stabilizes the cell membrane, provides fluidity and flexibility.

proteins

intergal (inside bilayer) and peripheral (outside the bilayer) transprotein (goes all the way through bilayer) JETRAT (junctions, emzymes, transport, recognition, anchorage and transduction)

carbohydrates

prefix -glyco, modifies other structures (ex: lipid into glycolipid)

passive transport

goes with the flow (high to low) w/o using energy

active transport

requires energy to be moved, going against the grain (low to high)

membrane transport

semi-permiable and selective, only specific molecules can enter through specific ways

cm to in conversion rate

2.54 cm in 1 in

magnification formula

measured size of image (ruler)/ actual size (life size)

steps for magnification calcs

before you start convert to the lowest unit present (mostly nanometers), use scale bar to find missing measurements, use a ruler for ruler measurements

light microscopes

use light to magnify via lenses, strudy dead OR living cells in color, cells are alive so you can study movwement, max mag is ~1500x and max resolution is ~0.3 microns

electron microscope

electron beams focused bt electromagnets, kills the cell in the process of creating a slide b/c of chemicals used, no movement visible, w/o stain there is no color, max mag ~300,000x and max res ~0.001 micron

resolution

smallest degree of detail visible through the microscope