biology 01

Cell Theory

a fundamental scientific theory in biology that provides a general understanding of life on Earth and its characteristics

Robert Hooke

he examined a slice of cork under the microscope he built

Cellula

latin word and is the origin of the word ‘cell’

Micrographia

contains the astonishing collection of copper plate illustrations of objects he observed under his own compound microscope

All organisms are made up of cells

1st Classical Cell Theory

Cells are the basic unit of life

2nd Classical Cell Theory

All cells come from pre-existing skills

3rd Classical Cell Theory

Matthias Schleiden, Theodor Schwann, Rudolf Virchow

they proposed the first three tenets MS TS RV

discovery of DNA

this prompted the addition of the next three tenets, called the Modern Cell Theory

Omnis cellula e cellula

All cells come from pre-existing skills

Genetic information is passed through DNA or RNA during cell division

1st Modern Cell Theory

Cells of the same species are mostly the same both structurally and chemically

2nd Modern Cell Theory

Energy flows occurs within cells

3rd Modern Cell Theory

99.9%

the genetic similarity between a human and a human

Mitochondria

• powerhouse of the cell, it makes the cell’s energy

• more energy needed = more mitochondria needed

Lysosome

a membranous sac filled with hydrolitic enzymes that digest worn-out cells, food particles, and macromolecules

Matthias Schleiden

• 1838

• German lawyer and botanist who discovered cell in plants

• he published a study of vegetable cell

Theodor Schwann

• 1839

• German physiologist who discovered that animal tissues are made up of cells

• he published a study of several slides of animal cells

Rudolf Virchow

• 1855

• he proved the last postulate by showing that cells play a role in body diseases

Anton Leeuwenhoek

• 1660s

• Father of Microbiology

• created his own microscope with higher magnification

Animalcules

includes protozoans and other unicellular organisms

Organelle

membrane-bound "little organs" inside cells that perform specific functions.

Cytoplasm

includes all organelles and the cytosol

Nucleus

the control center of the cell that houses DNA and nucleoli; surrounded by a nuclear envelope with pores

Nuclear envelope

double membrane enclosing the nucleus; continuous with the endoplasmic reticulum

Nucleolus

site of ribosome production

Nucleoplasm

fluid matrix inside the nucleus

Nuclear pores

regulate entry and exit of substances in and out of the nucleus

Skeletal muscle cells

cells that have one more nucleus

Red blood cells

cells that lose their nucleus when they mature

RMT

3 type of RNA

Ribosomal RNA

joins with proteins to form ribosome subunits

mRNA

carries genetic code from DNA to ribosomes

tRNA

assembles amino acids during protein synthesis

Deoxyribonucleic acid

DNA

Ribonucleic acid

RNA

Ribosomal RNA

rRNA

Messenger RNA

mRNA

Transfer RNA

tRNA

Ribosome

protein factory made of rRNA and protein; found free in cytosol or bound to rough ER

Endoplasmic reticulum

network of membranes involved in producing and transporting proteins and lipids

Rough ER

ER with ribosomes; makes proteins to be exported or sent to membranes

ER without ribosomes; makes lipids and detoxifies substances

Cisternae

flattened membrane sacs found in the ER and Golgi apparatus

Lumen

the internal space within the ER

Glycoprotein

a molecule made of protein and carbohydrate; produced in the RER

Golgi Apparatus

stacks of membranes that modify, sort, and package proteins and lipids

Cis face

the receiving side of the Golgi apparatus

Trans face

the shipping side of the Golgi apparatus

Vesicle

a small membrane-bound sac that transports materials in the cell

Endomembrane System

a group of organelles that work together to produce, process, and transport proteins and lipids (includes ER, Golgi, and vesicles)

Lysosome, peroxisome, vacuole

organelles that are responsible for cell maintenance LPV

Lysosome

a vesicle filled with digestive enzymes that breaks down waste, food, or damaged organelles

Hydrolytic enzymes

enzymes that break down molecules using water

pH

measure of acidity or basicity

Phagocytosis

the process of engulfing and digesting large particles or cells

Autophagy

the breakdown and recycling of a cell’s own components

Peroxisome

an single membrane bound organelle that detoxifies harmful substances and breaks down fatty acids

Hydrogen Peroxide

a toxic byproduct of metabolism that is broken down by peroxisomes

Vacuole

a large storage sac in plant cells that helps with structure, water balance, and storage.

Cell Sap

fluid inside the central vacuole containing water and dissolved substances

Pigments

molecules that give color

Plastid

plant cell organelles involved in photosynthesis, pigment storage, and food storage

Chloroplast

a plastid with chlorophyll that performs photosynthesis.

Chlorophyll

green pigment that captures light energy for photosynthesis

Thylakoid

flattened sacs in the chloroplast where light reactions occur

Granum or Grana

stacks of thylakoids inside the chloroplast

Stroma

the fluid inside chloroplasts that contains DNA and enzymes

Chromoplast

plastids that store colored pigments (red, orange, yellow)

Leucoplast

colorless plastids that synthesize and store starch or oil

Mitochondrion

organelle that produces ATP (energy) through cellular respiration

Cristae

inner folds of the mitochondrial membrane that increase surface area

Mitochondrial Matrix

the inner fluid space of the mitochondrion containing enzymes and DNA

Intermembrance Space

narrow region between the inner and outer membranes

Plasma Membrane

a selective barrier that controls what enters and leaves the cell

Phospholipid Bilayer

the two-layered structure of the plasma membrane

Cytoskeleton

network of fibers that provides structure, shape, and movement

Microfilament

thin filaments made of actin; involved in movement and muscle contraction

Microtubule

hollow tubes that help with cell shape, organelle placement, and form cilia and flagella

Intermediate Filament

medium-sized fibers that provide strength and anchor organelles

Cilia

short hair-like structures that move substances along cell surfaces

Flagella

long tail-like structures that help cells move (e.g., sperm cells)