chapter 3 Flashcards
who developed the cell theory
robert hooke
parts of the cell theory
- everything living is made of cells
- all cells come from preexisting cells
- cells are the smallest unit of life
- each cell maintains homeostasis at the cellular level
two types of cells
sex cells (germ cells) somatic cells
sex cells
- reproductive cells
- male sperm
- female oocyte (cell that turns into egg)
somatic cells
soma= body
all body cells except sex cells
how many cells do we have
trillions with over 200 different cells types
cell shapes
- disc- RBC
- sphere- fat
- long extensions- nerve
- toothpicks- smooth muscle
- cubed- columns, flat
functions of cells
- connect body parts
- cover & line organs
- store nutrients
- fight disease
- gather information
- control the body
- carry out the chemical activities needed to sustain life
two types of cells
prokaryotic & eukaryotic
prokaryotic cells
does not have membrane bound organelles or nucleus
eukaryotic
has membrane bound organelles & nucleus
trace elements
carbon
oxygen
hydrogen
nitrogen
key elements
- calcium (blood clotting)
- iron (carry hemoglobin)
- iodine (metabolism)
- sodium
- potassium
nucleus
- control center
- largest organelle
- contains genes to control cellular activity
mitochondria
- power house of the cell
- produces ATP
cell membrane
allows movement of molecules
-proteins are binding sites & receptors for hormones & chemical messages
ribosomes
proteins are produced here
lysosomes
digestive enzymes to break down non usable substances
cilia/ flagella
move substances along cell
- single- sperm
- multiple-cilia
golgi body
- transport proteins from ER to other parts of the cell
- 4-6 flattened sacs by the nucleus
- packages & sorts proteins & lipids
ER
- protein synthesis
- modifies materials to prepare for transport by golgi body
- system of double membrane channels continuous with nuclear envelope
cell membrane
regulates flow of materials inside& outside of body (lipid bylayer)
cytoplasm
holds cellular content (cytosol)
ribosomes
tiny granules composed of protein & rRNA site for protein synthesis
lysosomes
membrane bound sacs that contain digestive enzymes
cytoskeleton
internal structure in cytosol
-made of microfilaments & microtubules
centriols
microtubules used in cell division
membrane transport
- barrier
- lets nutrients in
- lets products & waste out
- selectively permeable
permeability
determines what moves in & out of a cell
impermeable
membrane that lets nothing in or out
freely permeable
membrane that lets anything pass
selectively permeable
membrane that restricts movement
how does selective permeability restrict
by
- size
- electrical charge
- molecular shape
- lipid solubility
active transport
requires energy
- carrier mediated transport
- vesicular transport
passive transport
no energy required
- diffusion
- carrier mediated transport
diffusion
movement of liquids from high to low concentration
concentration gradient
more solute in one part of a solvent than another
factors influencing diffustion
- distance
- molecule size (smaller moves faster
- temperature (hotter= faster)
- concentration gradient
- electrical forces (opposites attract)
channel mediated diffusioin
water soluble compounds & ions
factors influencing channel mediated diffusion
- size
- charge
- interaction with the channel
osmosis
diffusion of water across the cell membrane
enzymes
speeds up chemical reations
DNA
contains genetic material & instructions to make proteins
RNA
aides in making proteins at the ribosomes
endocytosis
packaging of extracellular materials in a vesicle for transport into a cell
receptor mediated endocytosis
target molecules bind to receptor proteins on membrane surface, forming vesicles
phagocytosis
vesicles form at plasma membrane to bring solid molecules into the cells “cell eating”
pinocytosis
vesicles for large membrane & bring fluids & small molecules to cell “cell drinking”
exocytosis
intracellular vesicles fuse with plasma membrane membrane releasing fluids from cell
mitosis
divides & duplicates two sets of chromosomes
stages of mitosis
interphase prophase metaphas anaphase telophase
oncology
study of cancer, tumors, & treatments
malignant
tumor that spreads fast & is life threatning
benign
non cancerous tumor that is slow growing & easily removeable
metastasis
spread of cancer cells to other areas of the body via lymphatic & circulatory systems through blood
carcinogen
cancer causing substance
treatment for cancer
- radiation
- chemotherapy
- surgery
steps to cancer development
- abnormal cell
- primary tumor
- metastasis
- secondary tumor
tumor (neoplasm)
- enlarged mass of cells
- abnormal cell growth & developement
meiosis
reproductive cells
- two devisions
- sperm & egg
- 23 chromosomes
proliferation
rapid reproduction of cell parts or organism
senescence
aging
hyperplasia
abnormal increase in number of cells
dysplasia
early development of cancer
in situ cancer
early cancer that has not metastisized
invasive cancer
cancer that has metastasized
apoptosis
death of cells that occurs normally & needs to be replaced
telomeres
caps on chromosomes that affect how cells age
