Biology Unit Final Flashcards
what is the formula for estimating actual size
field diameter/fit number
what is the formula for scale
actual size/drawing size
who disproved spontaneous generation and how
Louis Pasteur; bent the neck of the flasks in his experiment so that air could reach the broth but microorganisms and other particles would be caught in the s bend
what does staining a cell do
improve contrast between internal structures to produce better images
what is resolution
ability to distinguish detail within a structure
what are the 3 components of the cell theory
all living things are made up of one or more cells, cells are the smallest units of life, all cells are produced from pre-existing cells through cell division
what is an open system
one that must interact with its environment to maintain its existence
what is the difference between a simple and a compound microscope
simple has one lens whereas a compound has 2 or more
what are lysosomes
sacs containing chemicals to digest molecules
whats the Golgi apparatus
transports substances from ER out of the cell
whats the cell membrane
selectively permeable membrane that acts as a protective barrier for the cell and controls what goes in and out of it
whats the mitochondria
place where cellular respiration occurs to produce energy for the cell
what are centrioles
pairs that move toward the poles of the nucleus to start cell division
what are ribosomes
granules where proteins are produced
whats the nucleus
control center of the cell containing DNA and genetic material of the cell
whats the cell wall
rigid frame that provides strength and support to plant cells
whats cytoplasm
gel-like substance that contains nutrients and suspends the organelles
what are chloroplasts
contain chlorophyll and are the sight of photosynthesis
whats the vacuole
stores waste and other components in the cell
whats the nuclear envelope
double membrane surrounding the nucleus
what does smooth ER do
help produce lipids
what does rough ER do
help with protein synthesis
what are the major elements making up a cell
carbon, hydrogen, oxygen, nitrogen
what are the four major compounds in a cell
lipids, carbohydrates, proteins and water
what are trace elements
things present in tiny amounts that are essential to the health of the cell
3 similarities between plant and animal cells are
cell membrane, cytoskeleton made up of proteins and lipids, genetic material (DNA)
5 differences between plant and animal cells
animal cells have centrioles, animal cells have lysosomes, plants have cell wall, plants have chlorophyll, plants have a large central vacuole
what do all cells contain no matter their type
cell membrane, cytoplasm, chromosomes and ribosomes
what are prokaryotes
single-celled organisms that do not have a nucleus or membrane-bound organelles
what are eukaryotes
cells with a nucleus and membrane-bound organelles that work together to help the cell function
what is the other name for the cell membrane
phospholipid bilayer
whats an integral protein
goes throughout whole cell membrane
whats peripheral protein
rests more on the side of the membrane
what do carbohydrates do in cell membrane
act as a physical barrier and signal to the cell what’s good or bad
what does cholesterol do in cell membrane
regulates how fluid it is
what do glycoproteins do
stabilize cell
what organelle is responsible for transport
cell membrane
what’s included in the particle model
all matter is made up of particles, particles are constantly moving, particles are attracted to each other, particles have spaces between them
whats concentration
amount of a specific particle
whats diffusion
natural movement of particles from an area of high concentration to an area of low concentration
what does diffusion do in a cell
allows needed substances to enter and keeps other substances outside as well s removes waste to maintain cellular equilibrium
what determines the passage of materials through the cell membrane
molecule size, charge and whether they are soluble in lipids
whats osmosis
movement of water molecules from high water concentration to low water concentration
whats hypertonic and what happens to the cell in this environment
a solution that has a higher concentration of solute meaning there is less water than that in a cell causing water to leave the cell, making it shrink
whats hypotonic and what happens to the cell in this environment
a solution that has a lower concentration of solute meaning there is mroe water than that in the cell causing water to enter the cell, making it swell
whats isotonic and what happens to a cell in this environment
a solution that has the same concentration of solutes as that in the cell, making there no net movement of water molecules
what is the ideal state for a cell
isotonic
whats osmoregulation
control of water balance and the tendency of water to move into the plant cell to create pressure
whats crenation
process of losing water and shrinking in animal cells
whats cytolysis
swelling and bursting of animal cells
whats plasmolysis
cell membrane of plant cell shrinks away from the cell wall due to a hypertonic environment
whats deplasmolysis
rehydration of plant cell due to hypotonic environment
what’s facilitated diffusion
channels that allow small water-soluble molecules to pass through the membrane
whats active transport
the use of energy to transport something against the concentration gradient
what happens in endocytosis
a vesicle forms around the particle and the cell membrane pinches it off so that the vesicle is inside the cell
what happens in exocytosis
a vesicle forms around the material and is brought to the surface of the cell membrane where it is released outside the cell
what do recognition proteins do
allow cells to recognize each other
what do receptor proteins do
bind specifically with certain molecules to bring them into the cell by endocytosis
whats insulin
small protein that stimulates the rate of movement of glucose into the cells
what happens in hemodialysis
blood is removed from the body, cleansed in a special machine and then returned to the body
what happens in peritoneal dialysis
dialysate fluid is pumped into a catheter and as it becomes saturated with waste it is removed from the body and new dialysate fluid is added
whats desalination
process of removing salt from seawater
why is it better for cells to be smaller
there is less travel time between the sruface of the cell and the nucleus, making them more efficient and increasing the ability for transport
what has to happen for the most efficient transport within a cell
cell must have a large surface area in relation to its volume
whats a tissue
groups of cells performing the same function together
name and define the two organ systems in plants
shoot system - everything above ground
root system - everything underground
what is the dermal tissue/epidermis and what does it do
out layer of plant cells that protect the plant from disease and is responsible for the exchange of matter and gasses in and out of the plant
whats ground tissue
it makes up the majority of the plant and is found as a layer beneath the epidermis
what is vascular tissue responsible for
transport of materials throughout the plant
whats the xylem do
move water and dissolved minerals from the roots up the stem to the leaves where they are used in photosynthesis
what is the xylem made of
non-living cell wall cells
what does the phloem do
transports sucrose and other dissolved sugars from the leaves to other parts of the plant
what is the phloem made of
sieve tubes
what are sieve tubes
cells that are still alive but have lost their nucleus
what is merismatic tissue
unspecialized cells that can be divided infinitely to produce new cells
what happens when cells are no longer a part of the meristem area
they become specialized for a particular function
what is the leaf
a collection of tissues whose main purpose is to carry out and support the process of photosynthesis
where are cells containing chloroplasts found
in the ground tissue of leaves and sometimes in stems
what is photosynthesis and what is the word equation for it
a chemical rxn in which light energy is absorbed by the chlorophyll and converted into chemical energy that is stored as glucose
H2O + CO2 + light + chlorophyll = glucose and O2
what is cytoplasmic steaming
movement of chloroplasts
what is the opposite of photosynthesis
cellular respiration
what’s the purpose of cellular respiration
produces energy needed by the cell to carry out life processes
can photosynthesis happen in the dark
no; the plant stops manufacturing food but the process of cellular respiration continues
what are guard cells
specialized cells. that form tiny openings called stomata that allow gas exchange to happen easily
what do the stomata do
regulate the movement of gas
how do guard cells open
they accumulate potassium which causes water to enter by osmosis, resulting in them swelling up and open
what’s the purpose of guard cells
to allow fas flow and protect the leaves from losing too much water through the stomata
whats transpiration
process of water vapour leaving the leaf through the stomata
whats the cuticle and what does it do
waxy substance that resists attack from microorganisms and helps to reduce water loss
whats mesophyll
specialized ground tissues located between the upper and lower epidermis
what are the two types of mesophyll tissue
palisade and spongy
whats palisade mesophyll tissue
long rectangular cells responsible for photosynthesis
whats spongey mesophyll tissue
weirdly shaped cells with increased space between them that allow for gas exchange by diffusion through the leaf
what are lenticels
pores that provide an opening for transpiration to occur and allow gas exchange to and from the inner parts of the tree trunk
whats cohesion
attraction of water molecules to other water molecules
whats adhesion
the attraction of water molecules to molecules of other substances
whats root pressure
when water is drawn into the cells because of the presence of dissolved minerals which creates a higher solute concentration inside the cell
what does root pressure do
force water from a higher pressure in the roots toward the lower pressure in the leaves
what does evaporation do for the transpiration process
it creates a transpiration pull that pulls on adjacent water molecules and draws the water up the xylem in combination with adhesions and cohesion forces
why is turgidity important
the pressure in all of the cells combines to hold the green parts of the plant up to the sunlight
whats the sink
places where the products of photosynthesis are stored
what’s the place where products of photosynthesis are manufactured called
the source
whats phototropism
growth movement in response to light stimulus
what’s the difference between positive and negative tropism
in positive the plant will grow toward the stimulus whereas in negative it grows away from it
whats gravitropism
growth movement in response to earth’s gravitational force
whats auxin
a hormone that is manufactured in one area and transported to another location where in low concentrations it has the ability to initiate cell elongation towards a stimulus
how do plants feel gravity
they rely on heavy starch particles in specialized cells to indicate direction of gravity
