ch 2- cells Flashcards
living thing
anything that can move, respire, sense, grow, reproduce, equilibrium, excrete waste and take up nutrients
homeostasis
the maintenance of a relatively stable internal environment in the body, despite changes in the external environment
organism
living things made up of one or more cells
cell theory
- all living things are made up of cells
- cells are the smallest and most basic units of life
- all cells come from pre existing cells
prokaryotes
group of single-celled organisms with no nucleus and a circular loop of DNA. bacteria and arachaea are both prokaryotic
eukaryotes
a group of single and multicelled organisms with a nucleus and linear strands of DNA. animals, plants, fungi and protists are eukaryotics
plasma membrane
the phospholipid bilayer and embedded proteins which separate the intracellular environment from the extracellular environment. also known as cell membrane cytosol, the aqueous fluid that surrounds the organelles inside a cell
ribosomes
small RNA protein structure that is the site of protein synthesis. they either float freely in the cytoplasm or are attached to the rough endoplasmic reticulum
DNA- deoxyribose nucleic acid
a double-stranded nucleic acid chain made up of nucleotides. DNA carries the instructions for proteins which are required for cell and organism survival
membrane bound organelle
structure within a cell that is enclosed by a phospholipid bilayer
chromosome
the structure made of protein and nucleic acids that carries genetic information
nucleus
a double membrane- bound organelle that protects and confines the genetic information (DNA) of a cell. Inside the nucleus is a smaller structure known as the nucleolus which is the site of ribosome production
plasmid
a small, circular loop of DNA that is separate from a chromosome, typically found in bacteria
somatic cell
ny cell that is not a reproductive cell (such as sperm and egg cells). Somatic cells are diploid (2n), meaning they contain two sets of chromosomes – one inherited from each parent
mitosis
the cell division phase which involves the complete separation of sister chromatids and nuclei
germline cells
cells that are involved in the generation of gametes in eukaryotes
gametes
reproductive cells that arise from germline cells that contain half the genetic material (n) of a somatic cell. In humans, gametes are sperm and eggs
meiosis
a specialised form of cell division used to produce gametes in sexually-reproducing organisms
binary fission
the method of cell replication used by prokaryotes
micrometres- μm
unit of measurement where 1 mm =1000μm
table 2 Characteristics of each kingdom
domains and kingdoms of prokaryotes
domains- archaea and bacteria
kingdoms- archaea and bacteria
domains and kingdoms of eukaryotes
domains- eukarya
kingdoms- Animalia, Fungi, Plantae and Protista
organelle
a cellular structure that performs specific functions
cytosol
the aqueous fluid that surrounds the organelles inside a cell
cytoplasm
the cytosol and organelles inside the plasma membrane, excluding the nucleus
ribosomes
tiny structures made up of ribosomal RNA (rRNA) and proteins that fold into a large and small subunit. Cells have many ribosomes, which either float freely in the cytoplasm or are attached to the rough endoplasmic reticulum. Ribosomes assemble the building blocks to make proteins.
rough endoplasmic reticulum
A membranous chain of connected and flattened sacs which are coated with ribosomes. This allows the rough endoplasmic reticulum to synthesise and modify proteins. The rough endoplasmic reticulum typically surrounds, or is close to, the nucleus.
smooth endoplasmic reticulum
A membranous chain of connected and flattened sacs which are not coated with ribosomes. The smooth endoplasmic reticulum is responsible for the production of lipids in a cell.
golgi apparatus
Stacked flattened sacs that are the sites of protein sorting, packaging, and modification for use in the cell or export. Protein-filled vesicles often fuse with or bud off from the Golgi apparatus. Also known as the Golgi body.
lysosome
A membrane-bound vesicle that contains digestive enzymes. It is responsible for breaking down cell waste and toxins, acting like a garbage disposal.
mitochondrian
An organelle with a highly folded inner membrane surrounded by a second outer membrane. Mitochondria are the site of aerobic cellular respiration, a chemical reaction that produces the ATP required to power cellular processes. They also contain their own DNA and ribosomes. the primary site of energy production from aerobic cellular respiration
chloroplast
A double membrane-bound organelle that contains flattened, fluid-filled sacs that are the site of photosynthesis. Chloroplasts also contain their own DNA and ribosomes.
vacuole
A membrane-bound sac that is used for water and solute storage. Vacuoles can also play a role in maintaining plant cell structure.
plasma membrane
The plasma membrane is a selectively permeable barrier between the intracellular and the extracellular environment. It is made of a phospholipid bilayer which is studded with many molecules.
cell wall
A sturdy border outside the plasma membrane that provides strength and structure to plant, bacterial, and fungal cells.
vesicle
A small, membrane-bound sac that transports substances into or out of a cell, or stores substances within a cell.
cytoskeleton
A large network of protein filaments that start at the nucleus and reach out to the plasma membrane. The cytoskeleton is critical for maintaining shape and transporting vesicles around the cell. In the given fluorescence microscopy photo, the purple represents the cytoskeleton.
ribosomal RNA
a type of nucleic acid that is a key structural component of ribosomes
lumen
the space within a cavity which can act as a passage-way
membrane bound organelles
structure within a cell that is enclosed by a phospholipid bilayer
cellular respiration
the biochemical process in all living things that converts glucose into ATP. Can be aerobic or anaerobic respiration
matrix
the space inside the inner membrane of the mitochondria
crista (pl. cristae)
the fold of the inner membrane of the mitochondria
aerobic
requiring oxygen
anaerobic
requiring no oxygen
aerobic cellular respiration formula
C6H12O6+6O2-> 6CO2+6H20+36ATP
algae
a large diverse group of photosynthetic protists found in aquatic environments
granum (pl. grana)
a stack of thylakoids
thylakoid
a flattened sac-like structure inside the chloroplast. Thylakoids stacked upon one another make up a granum
stroma
the fluid substance that makes up the interior of chloroplasts
photosynthesis
the process of converting light energy, carbon dioxide, and water into glucose and oxygen
photosynthesis equation
6CO2+6H2O- sunlight + chlorophyll> CH12O6+6O2
chlorophyll
a green pigment found in the thylakoids of chloroplasts. It is responsible for absorbing light energy in photosynthesis
endosymbiosis
when one organism lives inside another in a mutually beneficial relationship
endosymbiosis theory
a theory suggesting that chloroplasts and mitochondria were once free-living organisms before being engulfed by a larger cell
key differences between plant and animal cells
plants have a cell wall, chloroplast and one large vacuole
ovum (pl. ova)
a fully mature female egg cell which, when fertilised, can divide and give rise to an embryo
red blood cells
cells that transport oxygen through the bloodstream and do not contain a nucleus
volume
the amount of space inside an object. Measured in (units of length)3 (i.e. mm3, cm3, m3)
surface area
the sum of the area of all exposed sides of
a three-dimensional shape. Measured in (units of length)2
222 (i.e.mm ,cm ,m )
ratio
a comparison between two things to show proportions
surface area: volume ratio (SA:V)
a comparison of the amount of surface area per unit of volume. In Biology, SA:V influences temperature regulation, and a
high SA:V leads to more effective transport into and out of cells
