BIO Midterm Studying

hydrothermal vents

spots on the ocean floor where hot gases and minerals escape from earth's interior into the water

prokaryotes

- earliest cells that lack membrane bound organelles

- no nucleus to hold DNA

nucleoid

non membrane bounded region in a prokaryotic cell where DNA is concentrated

cytoplasm (cytosol)

- the liquid portion of the cell outside the nucleus

- provides foundation for cellular structures in a cell

cell wall

- rigid layer of material that surrounds the cells of plants

- protection and filter for cells

cell membrane

- semipermeable barrier around a cell for protection

- regulates what enters and leaves the cell

- phospholipids

ribosomes

site of protein synthesis by linking amino acids dependent on RNA instructions to form polypeptide chains

pili

appendages that allow bacteria to attach to each other and to transfer DNA (among other things)

eukaryotes

organisms made up of one or more cells that have a nucleus and membrane-bound organelles

endosymbiosis

- theorized process in which early eukaryotic cells were formed from simpler prokaryotes

- one engulfed the other through mutual benefit

why do eukaryotic cells compartmentalize?

- volume grows faster than surface area

- larger cells require more materials and produce more waste, and there is less area to exchange the two

cytoskeleton

network of protein filaments within some cells that helps the cell maintain its shape and is involved in many forms of cell movement

nucleus

- part of the cell containing DNA and RNA and responsible for growth and reproduction

- contains chromosomes, and is where replication, translation, and transcription occurs

nuclear envelope

layer of two membranes that surrounds the nucleus of a cell

nuclear lamina

a netlike array of protein filaments that maintains the shape of the nucleus by mechanically supporting the nuclear envelope

nucleolus

found inside the nucleus and produces ribosomes

chromosomes

threadlike structures made of DNA molecules that contain the genes

nucleoplasm

fluid inside the nucleus that supports structure

nuclear pores

protein lined channels in the nuclear envelope that allow passage of certain materials between the cell nucleus and the cytoplasm

endoplasmic reticulum (rough)

- largest organelle in the cell, studded with ribosomes

- protein folding and provides transportation

endoplasmic reticulum (smooth)

- synthesizes lipids, and phospholipids (and steroids)

- metabolizes carbohydrates

- detoxification of drugs, poisons

- stores calcium

golgi appartatus

- processes proteins from rough ER, sorts them, and transports them

- primarily delivers to cell membrane, lysosomes, and vacuoles

vacuoles

- storage of materials (plants have one large vacuole, and animals have multiple smaller vacuoles)

- break down molecules and reduce cell hazards

lysosomes

- organelle containing digestive enzymes to break down wastes

- plant cells do not have this, animal cells do

peroxisomes

- breaks down materials in a cell using enzymes

- differ from lysosomes due to the golgi apparatus not delivering to it

centrosomes (centrioles)

cell organelle that aids in cell division, carries microtubules

mitochondria

- yes the mf powerhouse of the cell

- generates ATP through cellular respiration

chloroplasts

- organelles that capture the energy from sunlight and convert it into chemical energy in photosynthesis

what do plant cells have that animal cells don't?

chloroplast, cell wall, large vacuole, plasmodesmata

plasmodesmata

- channels through cell walls that connect the cell walls of other plant cells

- enables transport, communication

chromatin

DNA tightly wound around specific proteins

what is the difference in ribosomes attached to the ER or nuclear envelope over those that are freely floating?

- bound to ER or nuclear envelope, ribosomes make proteins for membranes or specific organelles

- freely floating make assorted

endomembrane system

- regulates protein traffic and performs metabolic functions in the cell

- nuclear envelope, ER, golgi apparatus, lysosomes, vesicles, vacuoles, plasma membrane work together to package, label, and transport lipids and proteins

- connected together though vesicles

vesicles

- small membrane sacs that specialize in moving products into, out of, and within a cell

- transports materials, recycles wastes, and destroys toxins

process of endomembrane system

1. the nucleus makes mRNA for creating proteins, which delivers to the ribosomes on the rough ER

2. the ribosome receives the RNA and makes the proteins in their primary structure, and is transported to rough ER

3. rough ER folds proteins in its secondary/tertiary structure, and is transported to golgi through vesicle

4. vesicle enters golgi from cis side (receiving end). golgi sorts the proteins into certain transport vesicles and packages them accordingly, leaves through the trans side (shipping end)

5. vesicles are delivered to: plasma membrane, lysosomes, vacuoles primarily

6. if the protein is transported out of the cell, through bulk transport, the protein will be pushed out of the cell from the cell membrane

cisternae

flattened stacked membrane folds

secretory proteins

proteins destined for release to the extracellular environment

hydrolases

- protein enzymes aiding in hydrolysis

- works best in acidic pH to facilitate digestion in the lysosome

phagocytosis

type of endocytosis (bulk transport) in which a cell engulfs large particles or whole cells

autophagy

- process in which lysosomes decompose damaged organelles to recycle their organic monomers

photosynthesis

plants use the sun's energy to convert water and carbon dioxide into sugars and oxygen

thylakoids

- flattened membrane sac inside the chloroplast

- used to convert light energy to chemical energy

grana

stacks of thylakoids

stroma

- fluid surrounding inside of chloroplasts

- contains needed enzymes and manages chloroplasts' reaction to changes

glycolysis

- first step in releasing the energy of glucose from cellular respiration

- takes place in cytoplasm and does not need oxygen

- glucose and 2NAD+ \----- 2 net ATP, 2NADH, 2 pyruvate, 2H2O

cellular respiration

- process that releases energy (ATP) by breaking down glucose and other food molecules in the presence of oxygen

- occurs in mitochondria

endosymbiotic theory

a theory that states that certain kinds of prokaryotes began living inside of larger cells and evolved into the organelles of modern-day eukaryotes

laws of thermodynamics

1) energy can not be created or destroyed, only converted from one form to another

2) entropy in the universe is always constantly increasing

entropy

- a measure of the disorder of a system at a molecular state

- will increase as energy is transferred or transformed

metabolism

sum of the chemical processes / reactions that occur within a living organism in order to maintain life

1. converting energy from food to power cellular processes

2. converting food to biological macromolecules to act as building blocks structurally

3. eliminates waste from metabolic process

potential energy

stored energy that results from the position or shape of an object

kinetic energy

the energy an object has due to its motion

thermal energy

- kinetic energy associated with the random movement of atoms or molecules

- heat energy that causes atoms in molecules to move faster

chemical energy

form of potential energy that is stored in chemical bonds between atoms

metabolic pathways

- series of enzymatic reactions that converts one biological material to another

- molecules that are altered and catalyzed by enzymes resulting in products

anabolic reactions

- needs energy to build molecules

- maintains order in localized regions (like cells)

- not spontaneous, endergonic reaction

catabolic reaction

- releases energy by breaking down molecules

- increases disorder