Quiz 3 CELLS Flashcards
CELL
the smallest unit of life (millions in the body)
PROTEINS in a cell
- enzymes, (catalyst for a chemical reaction)
- movement (contraction, transportation, etc.)
- codes of DNA
CARBOHYDRATES in a cell
- energy source
- structure, Identification Marker
LIPIDS in a cell
- make up a large part of the membrane
- main part of “defining a cell”
- “as soon as you mess with with the defining border, the cell dies”
Plasma Membrane
boundary between the cell and its environment, regulates what enters and exits the cell
made up of heads and tails (within the two heads)
heads: hydrophilic
tails: hydrophobic
Cytosol
- is the part of the cytoplasm that is not held by any of the organelles in the cell. On the other hand, cytoplasm is the part of the cell which is contained within the entire cell membrane^^
Nucleus
- contains DNA and genes
- (the DNA contains the information necessary for constructing the cell and directing the multitude of synthesis tasks performed by the cell in life and reproduction)^^
- coding allows the cells “to build” and “to do”
- most of the cells in your body are going to have your entire genetic code
Endoplasmic Reticulum
- a network of tubular membranes within the cytoplasm of the cell, occurring either with a smooth surface (no ribosomes; creation and STORAGE of lipids and steroids) or studded (with ribosomes; synthesis and packaging of proteins)^^
- communication network linking membranes
Golgi Apparatis
- rearrange/modify proteins
- part of breaking down a larger molecule
- makes it more transportable through the membrane
Mitochondria
“powerhouse”; where ATP is built/put together
Cytoskeleton
- responsible for cell shape, motility (movement) of the cell as a whole, and motility of organelles within a cell^^
- movement and stability
Ribosomes
part of endoplasmic reticulum; building blocks of proteins (amino acids)
Cilia
single hair-like projections (respiratory tract, female reproductive tract); MOVEMENT
Flagella
one single projection (sperm cell); MOTILITY
Plasma Membrane Folds
vili and microvilli increase surface area for more absorption, more efficient absorption
MEMBRANE TRANSPORT
Passive
- requires no energy
- simple diffusion
- facilitated diffusion
- osmosis
- filtration
MEMBRANE TRANSPORT
Active
- requires energy
- active transport
- endocytosis
- exocytosis
Simple Diffusion
movement of matter from area of high concentration to low
Facilitated Diffusion
diffusion across a membrane involving a carrier or channel
Osmosis
diffusion of a solvent across a semi-permeable membrane
Filtration
separation by the movement of matter through pores that discriminate based on their size
Active Transport
movement of matter from area of low concentration to high
Endocytosis
engulfing a large substance that doesn’t fit through a pore and cannot diffuse freely because of its polar nature
Exocytosis
expelling intracellular ‘stuff’ into the membrane or interstitial space
Membrane Potential
- ion concentrations on either side of the plasma membrane create a difference in charge between the inside and outside of a cell providing a source of energy
- the movement of ions occurs through membrane transporters, channels, and pumps
- constant ion fluctuations are triggered by CHEMICAL CHANGES, PRESSURE CHANGES, and ELECTRICAL STIMULI detected at the cell surface
Genome
refers to the total genes of an organism; genes are codes for structures or function
- the entirety of the human genome is contained within 46 (23 pairs) chromosomes-each chromosome coding for between 350 to 4,000 genes
Chromosome
single strand of DNA (each DNA strand contains b/w 45-245 million nucleotides (base pairs), segments of which are referred to as genes) 3 nucleotides code for 1 amino acid and as such our DNA/genes are codes for building proteins
Genes code for:
- Regulatory Proteins: “enzymes?”, allowing or inhibiting muscle contraction^^
- Structural Proteins: 5%, stability and elasticity of myofibrils e.g. “titin” serves to help a stretched or contracted muscle return to its relaxed length^^
Regulation of Gene Expression
includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products (protein or RNA)^^
- essential for viruses, prokaryotes and eukaryotes as it increases the versatility and adaptability of an organism by allowing the cell to express protein when needed^^
Protein Synthesis
the process by which amino acids are linearly arranged into proteins through the involvement of ribosomal RNA, transfer RNA, messenger RNA, and various enzymes^^
Mitosis
- is a part of the cell cycle in which chromosomes in a cell nucleus are separated into two identical sets of chromosomes, each in its own nucleus^^ – 2 cells each within the same DNA (somatic cells)
- result: two equal looking cells
Meiosis
a process in which a parent cell divides to produce cells with half the genetic material of the parent
2 gamete cells (sperm and eggs)
