AP Bio Unit 3: Cells

cell theory

cell theory

3 Interrelated observations that helps us understand and study life

Cell theory observations

1.All organisms are made up of cells 2.The cell is a fundamental unit of life 3.Cells come from preexisting cells

How does a cell's inside compare to its outside?

inside= stable while outside is unstable

Homeostasis of a cell

When the cell is at a certain ph range and salt concentration inside of the cell, important for inner cellular functions (chemical reactions and protein folding) , cell membrane maintains this

DNA (deoxyribonucleic acid)

genetic material, varying sequences of 4 different nucleotides that make each one special

RNA (ribonucelic acid)

used to direct synthesis of proteins

Ribosome

composed of a top large subunit and bottom small subunit, assembles proteins

Nucleus

Contains DNA of cell, determines timing of creating enzymes

Nucleolus

Within the nucleus, uses all chromosomes within the nucleus and their genes to make ribosomes in one area within the nucleus (1.produces ribosomal RNA and builds proteins in cytoplasm, 2.goes back to nucleus to assemble amino acids/ribosomes)

Vesicle

membrane bound container, moves materials around

Rough Endoplasmic Reticulum

A folded membrane continuous with nucleus, ribosomes on it, protein + membrane factory (site)

Golgi body (apparatus)

folded structure, modifies and sorts proteins and lipids

Cytoskeleton

dynamic structure inside the cell, helps move and maintain shape, 2 types of components (microtubules=big , microfilament=small)

Smooth endoplasmic reticulum

Missing ribosomes, produces lipids, detoxification

Lysosomes

specialized vesicle of Golgi body used for digestion and recycling of molecules (has digestive enzymes), can kill a cell if popped due to its acidity.

Vacuoles

Major component of plant cells (smaller in animal), stores water for turgor pressure (inflates cell)

Cytosol

Fluid that contains solutes inside it, concentration gradients, excludes organelles

Mitochondria

folded membrane structure (mitochondrial matrix + intermembrane space), generates ATP inside membrane as energy for the rest of the cell, originated from proteobacteria, metabolic functions, requires oxygen

Chloroplast

Only in plant cell, photosynthesis, folded membrane, originated from cyanobacteria

Cell Wall

outside cell membrane, found in plants and prokaryotic cells, maintains cell shape and size, provides protection, rigid, resists water pressure

Prokaryotic

cells without a nucleus, bacteria and archaea, small (to absorb nutrients), plasmids (circular DNA), not primitive

Eukaryotic

cells with a nucleus and organelles

Bacteria

commonly found prokaryote, walls made up of peptidoglycan

Archaea

Prokaryote found in extreme environments, closer related to Eukaryotes than bacteria evolution wise

organelles

smaller spaces in a cell specialized for different functions

central dogma

usual flow of information in a cell, DNA to RNA to protein

Endosymbiotic theory

Mitochondria and chloroplasts were their own prokaryotic cells at one point before being engulfed by a eukaryote cell based on the genetic similarities between these organelles and bacteria.

Nuclear envelope

boundary of the nucleus, has pores (large protein complexes) that allow molecules to enter and exit the nucleus