Chapter 4 Vocab Flashcards
what is a cell?
the smallest unit that can carry out all activities associated with life
what is cellular theory?
cells are the basic units of life, cells come from cells, and cells have a common origin
what are the basic functions of all cells?
maintaining homeostasis, specialized organelles, genetic instructions coded in DNA
How does the Plasma Membrane support homeostasis?
the plasma membrane acts as a selective barrier which allows specific materials in and out of the cell, separating the cell from the outside environment
what is surface area/volume ratio and how does it affect diffusion?
the size of the cell compared to its volume affects the rate in which products can diffuse within the cell. Smaller ratio= slower diffusion process
who first described cells using a self-made microscope?
Robert Hooke
What did Antonie van Leeuwenhoek discover using a self-made small lense?
bacteria, protists, blood cells, and sperm cells
What is light microscopy?
the study of stained and living cells. consisting of a tube with glass lenses on each end where visible light passes through.
what is magnification?
the ratio of the size of the image in the microscope compared to its actual size
what is resolution?
the minimum distance between two points at which they can both be seen separately
what is electron microscopy?
used to study the ultrastructure of cells, two types
what are the two types of electron microscopy?
transmission and scanning
what is cell fraction?
a technique used for separating parts of the cell for studying. cells are spun in a centrifuge, separating the extract into pellet and supernatant
what type of cell are bacteria and archaea?
prokaryotic
what is a eukaryotic cell?
characterized by highly organized and specialized membrane enclosed organelles
what are structures within the eukaryotic cell?
lysosomes, mitochondria, Golgi complex, ER,, nucleus and nucleolus, centrioles, microtubules, cytoplasm, ribosomes, and cell membrane
what are structures within the prokaryotic cell?
cell wall, ell membrane, Golgi complex, ribosomes, chloroplast, vacuole membrane, nucleus and nucleolus, ER, druse crystal, mitochondrion, cytoplasm, amyloplast, aphid crystal, and large central vacuole
what are the benefits of a cell membrane?
the compartments allow for specialization, chemical reactions carried out by enzyme bound membrane, allow for storage of energy
what is the nucleus?
the control center of the cell, houses DNA (including replication and transcription)
What is DNA replication?
occurs during cell division, when DNA is reproduced and passed on to two daughter cells
What is transcription of DNA?
DNA to mRNA occurs in the nucleus and moves to the cytoplasm where proteins are manufactured
What is chromatin?
DNA associates with RNA and certain proteins, tightly packs DNA
What is the function of the nucleoli?
synthesize ribosomal RNA
What is the function of the nucleoli?
synthesize ribosomal RNA
What is a ribosome?
an organelle found free in the cytoplasm or attached to certain membranes; synthesizes proteins (consists proteins and rRNA)
What is the endomembrane system?
a network of organelles that exchange materials through small membrane-enclosed transport vesicles
what does the smooth ER synthesize?
lipids and breaks down toxins
what does the rough ER synthesize?
secreted and membrane proteins
what is the Golgi complex?
consists of stacks of flattened membranous spaces called cisternae
what are the three portions of the Golgi stack?
cis face, trans face, medial region
what is cis face?
entry surface
what is trans face?
exit surface
what is medial region?
in between
what are lysosomes?
small sacs of digestive enzymes dispersed in the cytoplasm of animal cells only
what is the structure of primary lysosomes?
contain hydrolytic enzymes and synthesized in rough ER
How is the Golgi complex directed to sort enzymes to lysosomes?
by attached sugars
what do secondary lysosome do?
aid in cell digestion
what is a vacuole?
large, single, membrane-enclosed sacs (tonoplast is the membrane of the vacuole), play a significant role in plant growth and development
what are mitochondria and chloroplasts?
energy converting organelles that convert chemical or light energy into ATP. Both have their own ribosomes and DNA molecules
what is aerobic respiration
conversion of chemical energy in certain foods to ATP
what is the inter membrane space and matrix?
a double membrane forms two compartments
what is chlorophyll?
a green pigment that traps light energy for photosynthesis
what are the components of the cytoskeleton?
plasma membrane, microfilaments, intermediate filament, and microtubules
what are microtubules?
hollow cylinders that are rigid
what are microfilaments?
consist of intertwined strings of actin filaments, flexible solid fibers consisting of two intertwined polymer chains
how do microfilaments generate movement?
by rapidly assembling and disassembling
myosin and actin
what are intermediate filaments?
tough flexible fibers about 10 nm in diameter
what are cilia and flagella?
unicellular and small multicellular organisms that move through watery environments
what is glycocalyx?
surrounds many cells and allows cells to recognized one another, make contact, and form adhesive or communicating associations, contributes to mechanical strength
what are fibronectins?
organize the matrix and help cells attach to it
where are integrins?
in the plasma membrane maintain adhesions between ECM and intermediate filaments nd microfilaments inside the cell
what does a plant cell wall contain?
cellulose
