Unit 2 Flashcards
First people to identify and observe cells?
Leeunwehoek - first scientist to observe cells
Robert Hooke - first to use the term “cell”
Cell theory
idea that all living things are composed of cells, because they’re the basic units of structure and function in living things, and new cells are only produced from existing cells
Why do cells rely on SA?
because it makes it easier for the villi to surround the nutrients, while the microvilli protects the cell by moving small things around the outside of it
Why are smaller cells more efficient than larger ones?
a larger cell has a reduced surface-area-to-volume ratio, and the amount of diffusion of nutrients, wastes, and gases across the cell membrane is reduced.
Why are humans multicellular?
b/c the vili would be too small to allow for efficient movement of nutrients and oxygen into the cell and wastes
Prokaryotic cells
no membrane bound nucleus
Eukaryotic
has a membrane bound nucleus
fimbriae
hair like structures on the outside of a prokaryotic cell and help attach to appropriate surfaces
Nucleoid
instead of having a true nucleus, prokaryotic cells have a nucleoid which contains the cell’s DNA and isn’t surrounded by a nuclear envelope.
plasma membrane
forms a barrier between the inside and outside of the cell to regulate what crosses that barrier
cell wall
in the outermost layer of plant cells ONLY, it protects the cell from dehydration and external environment, and maintains typical shape
capsule
a gel like coating outside of cell wall
flagella
has a long, thin protein extensions that rotate like a propeller, allowing them to push the cell forward
ribosomes
synthesises proteins
phospholipid bilayer
part of the plasma membrane, has cholestorol to help maintain fluidity
cytoplasm
jellylike substances that surrounds the inside of the cells, provides extra protection
plasmids
rings of DNA located within the cytoplasm
Archea
type of bacteria
Cell wall - usually
has - plasma membrane & ribosomes
doesn’t have - nucleus, peptidoglycan, or membrane bound organelle
Bacteria
cell wall - usually
has - peptidoglycan, plasma membrane & ribosomes
doesn’t have - nucleus or membrane bound organelle
eukaryotes
cell wall (plants) - sometimes has - plasma membrane, ribosomes (larger than prokaryotic), nucleus, phospholipid bilayer doesn't have - peptidoglycan
nuclear envelope
a double membrane separating the nucleus and cytoplasm
chromatin
consists of DNA and proteins becomes chromosomes when the cell is ready to undergo cell division
nucleolus
a region within the nucleus where a type of RNA, called ribosomal RNA (rRNA), is produced
vesicles
membrane bound sacs that stores and transport substances & unique organelle
endoplasmic reticulum (ER)
smooth & rough combined an interconnected system of membranous channels and sacs that is physically continuous with the outer membrane of the nuclear envelope.
golgi apparatus
has cisternea, collects, sorts, packages, and distributes materials such as proteins and lipids
vacuole
a large membranous sac
Rough endoplasmic reticulum
cisternea, ribosomes, large folding, and transport of proteins for export
cell wall eukaryotes
Protecting the cell while remaining permeable.
how does the endomembrane system acts as a transport system?
because the organelles that compose it are connected directly or by transport vesicles.
Explain why plant cells need both chloroplasts and mitochondria
Chloroplasts allow them to capture solar energy to produce organic molecules. Plant cells need mitochondria to break down the organic molecules to produce ATP which is used for energy in their metabolism.
Animal & plant cell ONLY
mitochondria
As the size of a cell decreases, the ratio of its surface area to volume
increases
NOT in a Prokaryotic cell
mitochondria
What is the role of proteins, steroids, and phospholipids in the fluid-mosaic model.
Phospholipids compose a bilayer that separates the inside from the outside of the cell. Steroids in the bilayer regulate the fluidity of the membrane. Proteins present in the membrane contribute to its structure, the passage of molecules across the membrane, signaling pathways, cell recognition, and enzyme reactions.
extracellular matrix in an animal cell functions
- Collagen and elastin fibers provide structure
- Fibronectin binds to integrin in the membrane & signal the cell’s cytoskeleton.
- Proteoglycans assist in cell signaling
difference between adhesion, gap, and tight junction
Adhesion junction—mechanically attaches to cell membrane
gap junction—allows cells to communicate through channels;
tight junction—connects plasma membranes, creating a tight barrier ; zipper
fluid mosiac model structure
shows a plasma membrane, states that components like (proteins, glycolipids) form a pattern in the fluid like environment
channel proteins
allow a substance to simply move across the membrane, w/o hydrogen ions & ATP aren’t produced
carrier proteins
they combine w/ a substance to move it across the membrane
cell recognition proteins
glycoproteins that help the body recognize when there’s a bad cell
receptor proteins
a protein that binds to a specific molecule
enzymatic proteins
carry out metabolic reactions directly
passive diffusion
moves from high to low, concentration gradient
facilitated diffusion
the movement of molecules that only take place if it is helped by a specific protein carrier and chanel in the membrane, can occur in either direction depending on the concentration gradient
prokaryotic & eukaryotic
cytoplasm, ribosome, bacteria
inegral proteins
chanel, carrier, receptor, - travel through the membrane
peripheral proteins
cell recognition, glycogen - stay on the outside
embedded proteins
control movement across plasma membrane
- channel proteins
- carrier proteins
- cell recognition
- receptor proteins
- enzymatic proteins
smoothe endoplasmic reticulumn
small dough foldings, no ribosome, it transports proteins for export, no cisterna
osmosis
moves high to low
less water+ more solute = high osmotic pressure
more water+ less solute= low osmotic pressure
selectively permeable
the plasma membrane, because only certain substances can cross it such as small noncharged molecules (oxygen, carbon dioxide, glycerol
diffusion
the movement of molecules from a higher to a lower concentration
hypotonic
a cell gains water because concentration is higher inside so there’s less water
hypertonic
a cell loses water because there’s less water outside the cell
isotonic
- the same amount of water that moves in moves out state of equalibrium on either side of the membrane
- (good) animal cell
- (bad) plant cell
crenation
when a lot of water leaves the cell, ruining the structure
active transport
from low to high concentration, requires ATP
sodium potassium pump
1 ATP = 2 K (in) & 3 Na (out)
exocytosis
takes something to the cell wall to go outside
endocytosis
takes something into the cell, the plasma membrane surrounds pinches it off and moves it inward (insulin)
cellular junction
cells come in close or physical contact with other cells to communicate
tight junction
found lining the digestive system
PM connects adjacent cells
gap junction
physically connects with proteins, creates a channel for things to travel through
plasmodesmata
little holes in a plant cell, that allows thing to pass through
tissue types
Epithelial - covers the body, lines body cavities
Connective
Muscular
Nervous
epthelial (human)
External - protections from injury, regenerate liver, prevents desiccation
internal - secret mucus (goblet), remove debris (cilia), absorption
sits on a basement membrane
Epthelial Classification
Squamous - flattened
- Simple (one) - lungs, blood vessels, diffusion
Stratified (multiple) nose, mouth, esophagus, anal canal, vagina
- Cuboidal - simple cubed shaped, absorption, gastric pits, the lining of kidney, pancreatic islets
- Columnar (simple) - digestive tract, absorption
Pseudostratified removes impurities
connective tissues
binds organs together, produces blood cells, stores fat
connective (CT)
binds organs together, produces blood cells, stores fat
collagen
main structural protein in the ECM
- gives skin strength & elasticity
adipose & reticular CT
enlarged fibroblasts filled with fat, important for insulation and storage
transport of membrane assisted
pinches off ER and goes to golgi
secretory of membrane assisted
Pinches off the golgi and goes to outside the cell
phagocytosis
cellular ingestion using the PM and pseudopods
fuses with lysosome and digestion occurs
pinocytosis
PM surrounds and an indent is made in it then is pinched off
types of endocytosis
phagocytosis, pinocytosis, and receptor-mediated
receptor-mediated
binds with receptor proteins and moves to a pit in the PM “coated pit”
extracellular matrix
a complex meshwork of polysaccharides and proteins made by cells
structural proteins
used to build structural components of the body like bones uses collagen, elastin
adhesive proteins
cell to cell; fibronectin
adhesive junction
connect cytoskeleton
most common type
reticular
small support structures of fibrousis matrix
elastic
stretchy elastin protein
loose fibrous CT
supports and binds, under the skin, allows expansion
covers muscles, nerves, and blood vessels
dense fibrous CT
high density and tightly packed
support of muscles and bones
dermis of skin
tendons
connect muscle to bone
ligaments
connect bone to bone
cartilage
dense fibrous CT, smooth surfaces, joint movement
Lacunae
where the cartilage sits
Types of cartilage
hyaline- common found in the trachea
elastic- stretchy and is the outer ear
fibrocartilage- tension it is the disk in our spine
Bone
Rigid CT
Inorganic salts being calcium and phosphate
Collagen fibers interlaced for flexibility
Provides oxygen for blood which helps broken bones repair
Living tissue that is compact and spongey
osteoblasts
secret bone and become trapped by doing so
osteocytes
calcium storage
osteoclasts
resorbs bone
blood
matrix noncellular
plasma 55%, red/white blood cells 45%, platelets- clot blood
muscular tissue
actin and myosin proteins
muscle contraction
Skeletal muscle MT
attached to tendons, striations, fusion of cells containing multiple nuclei, voluntary control, moves body parts
Smooth MT
no striations, spindle shape, thick over thin, only one nucleus, line digestive organs and blood vessels, peristalsis, involuntary control
Cardiac MT
lines walls of heart, has striations, single nucleus, pumps blood
Intercalated disc- connects cells end to end and promotes an electrical current
Involuntary control
Nervous tissue
contain neurons that have a cell body, dendrites that receive information and sends it to the cell body, axon where the message is sent down and is covered by the myelin sheath
Found in the brain and spinal cord
sensory input and motor output
neuroglia
more common than neurons and support neurons
Body cavities and membranes
anterior- upward, posterior- downward, ventral- belly,
dorsal- back
superior- pertaining to the head, inferior- pertaining to the feet, medial- the middle of, proximal- close to the center of gravity, distal- father from the center of gravity
ventral cavities
thoracic- lungs and heart
abdominal- spleen and liver contains most of digestive system
Pelvic- some large intestine and rectum bladder and reproductive system
diaphragm
separates thoracic and abdominal cavity and helps with breathing
dorsal cavities
cranial cavity- holds the brain
vertebral canal- holds the spinal cord
body membranes
Mucous, serous, synovial, meninges
mucous ET and LCT
goblet cells, lines dig, resp, uri, and repro
serous ET and LCT
lines thoracic and abdominal cavities, watery lubricant, support and compartmentalize
synovial
line joints, lubricate with cartilage
meninges
protective brain cover
integumentary system
epidermis, dermis, skin, synthesize vitamin-D, sensory input, homeostasis
cardiovascular system
heart, transport blood, temp ph, and fluid homeostasis
lymphatic and immune
lymphatic vessels and nodes, spleen, protection from disease, absorbs fat, collect interstitial fluid
digestive
ingest and digest, absorb and eliminate, fluid homeostasis
respiratory system
lungs, exchange gases, ph homeostasis
urinary
kidneys and bladder, remove metabolic waste, ph and fluid homeostasis
musculoskeletal
bones and muscles, support and protection, movement and heat, store minerals, produce blood cells
nervous
brain and spinal cord, sense process motor, coordination
endocrine
organs and glands, hormones, coordination, homeostasis
reproductive
testes and ovaries, produce and transport gametes, nurture offspring
List a major organ found in 4 organ system
Integumentary - skin;
cardiovascular - heart;
lymphatic and immune - lymph nodes;
digestive - small intestine;
identify 2 organ system that protect the body from disease
Integumentary, and lymphatic and immune
Meristematic tissue
allows a plant to grow its entire life because it retains cells that forever have the ability to divide and produce more tissues so PLANTS GROW TILL DEATH
Apical meristem
the type of meristematic tissue that is present in the tips of all growing stems and roots of a plant- VERTICAL growth types: Epidermal tissue - outer cover Ground tissue - fills interior Vascular tissue - water & sap transport
Epidermal tissue
forms the outer protective covering of a herbaceous plants (NOT A TREE) ; plant skin
Ground tissue
fills the interior of a plant; produces toxins, hormones & pigments. these cells are parenchyma, collenchyma, and sclerenchyma
Vascular tissue
transports water & nutrients in a plant and provides support
epidermis
the complex tissue covering the entire body of non woody (herbaceous) and young woody plants
cuticle
a waxy covering for air exposed epidermal cells; minimizes water cells
root hairs
long slendar projections in certain epidermal cells; increase the surface area of the root for water & mineral absorption
parenchyma
- most abundant, thinnest cell wall, photosynthesis
- found in all organs of a plant, alive at maturity
collenchyma
gives flexible support to immature regions of plant body
- thicker primary wall
- prominent corners, often in bundles
sclerenchyma
- thick secondary cell wall that forms between the primary cell wall and plasma membrane
- contains lignin, support mature regions of a plant
- dead at maturity
ligin
a highly resistant organic substance that makes cell walls tough, inside secondary cell wall
xylem (vascular plant tissue)
transports water and mineral from roots to stem to leaves (transpiration) ]
phloem (vascular plant tissue
transports sugar and organic molecule like hormones throughout the plant (translocation)
1 phloem – 1 companion cell (has nucleus)
Vascular tissue locations(plants)
roots - vascular cylinder
stem - vascular bundles
leaves - leaf veins
periderm
epidermal tissues for older woody trees
stomata
allows water to leave cells
tracheids & vessel element
two types of xylem cells that stack to form a straw to tranport water
vessel - great transporter
tracheids - not a good tranporter
root system
penetrates soil function - anchorage, absorption, and soil
shoot system
transports water & sap
terminal bud - allows plant upward growth
lateral growth - only possible for the stem for certain plants
stem - main axis of a plant, transports water & sap
leaves - require water and and sunlight to carry on photosynthesis
node & internode
node - occurs where leaves are attached to the stem, internode - the region between the nodes
petiole
the stalk that attaches the blade to the stem
blade; leaf margin
- maximizes sunlight
- photosynthesis
blade
wide portion of the leaf
axillary bud
Bud located in the axil of a leaf.
functions of leaves
maximizes sunlight
specialized tissue
photosynthesis
tree types
Deciduous - loose leaves
Evergreen - loose needles
Modified - in cacti (holds water)
symbiosis
Nitrogen fixing bacteria, the fungus colonizes the plants roots and is provided with carbohydrates, sucrose and glucose, in return the plant benefits from the fungi ’s higher water and mineral absorption capabilities
Compare the structure and function of roots, stems, and leaves
Roots - the root hairs, with their large surface area, allow for uptake of water and minerals. The branching allows them to stabilize the aboveground portion of the plant.
Stems - allow for continued growth and contain xylem and phloem for transportation of water and nutrients through the plant.
Leaves - allow for sunlight to reach the chloroplasts and gases can diffuse easily. The petiole allows for maximum exposure to the sun.
monocots (angio sperm)
Seed - 1 cotyledon ( seed leaf) Root - Xylem & phloem in a ring (fibrous - many) Stem - scattered Vascular bundles Leaf - veins form a parallel pattern Flower - splits in 3 and multiples of 3 Pollen - One pore or slit
Eudicots (angio sperm)
Seed - 2 cotyledon (seed leaf)
Root - phloem between arms of xylem (taproot)
Stem - vascular bundles in distinct ring
Leaf - veins form net pattern
Flowers - parts in 4’s, 5’s, or multiples
Pollen - 3 pores or slits
TREES are eudicots!!
List monocots & eudicots plants
Monocots: corn, grass, palms
Eudicots: dandelions, oak trees, potatoes, kale
angiosperm
a plant that has flowers and produces seeds
pericycle
The first layer of cells within the vascular cylinder
tap root
(eudicots only!) the first or primary root grows straight down
fibrous root system
consists of many fine roots similar in diameter
- mature plants have both!
How does a plant control what enters the vascular bundle?
through a Casparian strip, which requires water and minerals to pass through the cells to enter the xylem
Monocots and & Eudicots both have
Dermal tissues
Ground tissues
Vascular
guard cells
control water movement
open stoma
transports potassium, water follows (osmosis) into vacuole = turgid
closed stoma
potassium leaves vacuole, water follows (transpiration) = good
transpiration
- UNIDIRECTIONAL -
water evaporates through leaves, creating tension to pull water up, cohesion keeps it in a continuous column, adhesion keeps it in place
translocation
- BIDRECTIONAL -
sugar is actively transported into phloem at a source, and water follows by osmosis. The resulting increase in pressure creates a flow, which moves water and sugar to a sink.
cellular respiration
The mitochondria of a eukaryotic cell is the site of
