Unit 2 exam Flashcards
What functional groups are present in all amino acids?
amine group (NH2) and carboxyl group (COOH)
What functional group can act as an acid?
carboxyl
which functional group can act as a base?
amine (NH2)
what is another name for a condensation reaction?
dehydration synthesis
what’s an example of a polysaccharide?
cellulose
what can amylase breakdown?
glycogen, starch, amylopectin
What are the storage polysaccharides?
starch and glycogen
Which macromolecule is cellulose?
carb
What is a phospholipid?
two fatty acids and a phosphate group are attached to a glycerol
What is cholesterol?
a type of steroid, which is a component of animal cell membranes and a precursor from which other steroids are synthesized
What are the bonds between amino acids?
peptide bonds
What are polynucleotides made of?
a nitrogenous base, pentose sugar and one or more phosphate groups
What links nucleotides together?
phosphodiester bond
What do all cells share?
plasma membrane, cytoplasm, chromosomes, ribosomes
How are prokaryotic cells are characterized?
no membrane bound nucleus, nucleoid, no membrane bound organelles, cytoplasm bound by a plasma membrane
What does the endomembrane system consist of?
nuclear envelope, endoplasmic reticulum, golgi apparatus, lysosomes, vacuoles, plasma membran
What does the smooth ER do?
makes lipids and detoxes drugs and poisons
What does the rough ER do?
secrete glycoproteins, vesicles, and membrane proteins
What does the golgi do?
modifies products of the ER and sorts and packages them
What do lysosomes do?
digest macromolecules (basically stomach)
What are vacuoles?
large vesicles from the ER and Golgi
What are perioxisomes?
oxidative organelles that carry out chemical reactions
What is the endosymbiont theory?
early eukaryotic ancestor engulfed other cells that became the host cell (basically ate other cells and those became organelles)
What do cristae do for mitochondria?
present a large surface area for enzymes that synthesize ATP
What do chloroplasts do and where are they located?
they contain a green pigment called chlorophyll, and other enzymes that function in photosynthesis and is in leaves and other green organs of plants and algae
What are the structures of chloroplasts?
thylakoids (which form granum) and stroma
Explain how peroxisomes work
they contain enzymes that remove hydrogen atoms and transfer them to oxygen, creating H2O2 (hydrogen peroxide), which can help break down fatty acids and detoxify alcohol
What does the cytoskeleton do?
supports the cell, helps it maintain its shape, and interacts with motor proteins for cell motility
How do vesicles and other organelles move?
they use their motor protein feet to travel along to cytoskeleton
What are the three types of fibers that make up the cytoskeleton (listed from largest to smallest)?
microtubules, intermediate filaments, microfilaments
What do microtubules do?
shape the cell, guide movement of motor proteins, and separate chromosomes during cell division
Where are cilia and flagella located?
sperm, lining of the respiratory tracts
What do microfilaments fo?
help support the cell’s shape and forms a cortex just inside of the plasma membrane
What do intermediate filaments do?
they support cell shape and fix organelles in place
What are plasmodesmata?
channels that connect plant cells
What do tight junctions do?
everything is pressed tightly together to limit the leaking of extracellular fluid
What do desmosomes do?
fasten cells into strong sheets
What do gap junctions do?
provide cytoplasmic channels between adjacent cells
What are structural isomers?
have different covalent arrangements (contain the same atoms, but they are in a different structure)
What are cis-trans isomers?
have the same covalent bonds but the atoms are in different places (structure looks the same but atoms have swapped places)
What are enantiomers?
isomers that are mirror images of each other (like hands)
What part of organic molecules are most commonly involved in chemical reactions?
functional groups
How do cells in multicellular organisms communicate?
signaling molecules
What are cell junctions and what kind of communication do they do?
direct connections between neighbors and direct signaling
Can some cells communicate through direct contact?
yes, some animal cells
What is paracrine signaling?
local signaling when secreted messenger molecules travel a short distance (ex: growth factors in nearby cells)
What is synaptic signaling?
occurs in the nervous system (neurotransmitters)
What is endocrine signaling?
signaling in animal specialized cells which release hormones and can travel far
What are the three phases of cell signaling?
signal reception, signal transduction, cellular response
What is apoptosis?
programmed cell death
