Chapter 3 Flashcards
size & shape of cells
vary in size & shape
microscopic
composition of cells
cytoplasm
organelles
plasma membrane
location of cytoplasm
fluid in cells
location of organelles
specialized structures in cytoplasm
location of plasma membrane
surrounding the cell
function of plasma membrane
boundary
selectively permeability
2 layered membrane
what is plasma membrane made of
(2 layered membrane)
-phospholipids
-protein
function of cytoplasm
substance from nucleus to plasma membrane
contains cytoskeleton
cytoskeleton
framework, support, movement
microfilaments & microtubules
what are ribosomes made of
2 sub units of ribosomal RNA (rRNA)
location of ribosomes
attached to rough ER
free in cytoplasm
function of ribosomes
makes enzymes & proteins (protein factories)
endoplasmic reticulum (ER)
sacs & canals
carries through cytoplasm
rough ER
transports proteins made by ribosomes
smooth ER
synthesizes chemicals, makes a new membrane
location of golgi apparatus
flattened sacs near nucleus
function of golgi apparatus
(chemical processing & package center)
collects chemicals to move from smooth ER outside plasma membrane
mitochondria
inner & outer membranous sacs
function of mitochondria
(power plants)
1 DNA molecule
energy releasing chemical reactions (cellular respiration)
lysosomes
membrane enclosed packets containing digestive enzymes
function of lysosomes
- protective function (eat microbes)
- formerly thought to be responsible for apoptosis (programmed cell death)
centrosome
- microtubule
- centrioles
microtubule
organizing region of cytoskeleton
centrioles
paired organelles within centrosome
moving chromosomes during cell reproduction
nucleus
control center
genome
making proteins
determine cell structure & functions
component structures in nucleus
nuclear envelope
nucleoplasm
nucleolus
chromatin granules
nucleus involving DNA
- DNA becomes tightly coiled chromosomes during cell division
- 46 clear chromosomes contain DNA
cell extensions
- microvilli
- cilia
- flagella
what is a cell extensions
extending beyond boundary of a cell
microvilli
short extensions
slight movement for cell absorption
cilia
hairlike extensions
sensory function
moves wavelike to propel mucus
flagella
single projections
act as “tail” of sperm
every human cell has a designated function:
maintain the cell
regulate life processes
specialized functions of a cell:
differ depending on number and type of organelles
2 types of membrane transport:
Passive
Active
what is a membrane transport
move substances in and out of cell
passive transport
- no ATP
- down concentration gradient
active transport
- uses ATP
- only in living things
- up concentration gradient
Passive transport processes
Diffusion
Dialysis
Osmosis
Filtration
Diffusion
scatter evenly throughout space
high to low concentration
diffusion equilibrium
solutes move through channels or carriers in membrane
equality of concentration of solution on both sides of membrane
semipermeable membranes
pores that allow only certain substances to pass through
dialysis
may have semipermeable membrane
uneven distribution
used in medical procedures
osmosis
passive movement of water molecules when some cannot cross membrane
produces equilibrium by diluting concentrated solutes
osmotic pressure
filtration
movement of water and solutes caused by hydrostatic pressure on one side of membrane
active transport processes
- ion pumps
- phagocytosis
- pinocytosis
ion pumps
protein complex in cell membrane
use ATP to move substances across membrane against concentration gradient
examples of ion pumps
(ion pumps work with glucose & amino acids. ions are transported)
- sodium - potassium pump
- calcium pump
phagocytosis
cell eating
protective mechanism to destroy bacteria or debris from tissue damage
pinocytosis
cell drinking
engulfs fluid or dissolved substances
cell growth
proteins determine structure & function of cells
protein synthesis is directed by 2 nucleic acids
nucleic acids
DNA
RNA
structural & functional proteins
structure:
collage & keratin
functional:
hormones, enzymes, channels & receptors
types of cell growth
- DNA
- RNA
- protein synthesis
shape of DNA
spiral staircase (double helix)
DNA
46 chromosomes in nucleus
DNA base pairs are made of
deoxyribose (sugar)
phosphate
gene
sequence of base pairs in DNA
indirectly determines cell structure & function
RNA
genes that do not code directly for proteins
protein synthesis
subunits made of nucleotides
3 types of protein synthesis
transcription
mRNA pass from nucleus to cytoplasm to direct protein synthesis in ribosomes & ER
translation
what is protein synthesis
occurs in cytoplasm
genetic info passes from nucleus to cytoplasm
transcription
DNA separates to form mRNA
translation
mRNA transcript to synthesize proteins in cytoplasm in ribosomes
codon
series of 3 nucleotide bases in mRNA that acts as code for amino acid
transfer RNA (tRNA)
carries amino acid and anticodon
tRNA brings amino acid to mRNA
steps for cell reproduction
- cell life cycle - reproduction
- DNA replication
- Mitosis
what is cell life cycle
reproduction of cell, division of nucleus and the cytoplasm
2 daughter cells from division
interphase
interphase
when cell is not actively dividing
DNA replication
half of DNA becomes whole molecule identical to original DNA
mitosis
cell division that distributes identical nuclear chromosomes (DNA) to each new cell formed
steps of mitosis (PMAT)
Prophase
Metaphase
Anaphase
Telophase
prophase
chromatin granules become organized
pairs of linked chromatids
centrioles move away from nucleus
nuclear envelope disappears
spindle fibers appear
metaphase
chromosomes align across center cell
spindle fibers attach themselves to each to each chromatid
anaphase
centromeres break apart
separated chromatids > chromosomes
chromosomes are pulled to opposite ends of each cell
cleavage develops
telophase
cell division completed
nuclear envelope & nucleoli in daughter cells
cytoplasm divided (cytokineses)
what happens after telophase
daughter cells fully functional ending mitosis & entering interphase
results of cell division
two identical cells
growing tissues, replacing old or damaged cells
differentiation
daughter cells specialize & from different tissues
neoplasms (new tumors)
abnormalities of mitotic division can produce malignant or benign tumors
anticodon
tRNA complements mRNA codon