ATDH EXAM STUDY MATERIAL 2024-2025
Cell membrane - ANSWER Hold cellular components and are mainly composed of
phospholipids, cholesterol, and proteins
Organelles - ANSWER Cellular compartments enclosed by phospholipids bilateral
(membrane-bound)
Are located within the cytosol (aqueous intracellular fluid) and help make up the
cytoplasm
Only eukaryotes contain membrane-bound organelles
Nucleoid - ANSWER Where do prokaryotes keep their genetic material
Nucleus - ANSWER Primarily functions to protect and house DNA
DNA replication and translation occur here
Nucleoplasm - ANSWER Cytoplasm of the nucleus
Nuclear envelope - ANSWER Membrane of the nucleus
Contains two phospholipid bilayers with a perinuclear space in the middle
Nuclear pores - ANSWER Holes in the nuclear envelope that allow molecules to
travel in and out of the nucleus
Nuclear lamina - ANSWER Provides structural support to the nucleus, as well as
regulates DNA and cell division
Nucleolus - ANSWER Dense area that is responsible for making rRNA and
producing ribosomal subunits
Ribosomes - ANSWER Work as small factories that carry out translation
Composed of ribosomal subunits
Rough er - ANSWER Continuous with the outer membrane of the nuclear envelope
,and is "rough" because it has ribosomes embedded in it
Lumen - ANSWER Inside of the rough er
Smooth er - ANSWER Not continuous with other membranes
The main function is to synthesize lipids, produce steroid hormones, and detoxify
cells
Golgi apparatus - ANSWER Made up of cisternae (flattened sacs) that modify and
package substances
Lysosomes - ANSWER Membrane-bound organelles that break down substances
(through hydrolysis) taken in through endocytosis
Transport vacuoles - ANSWER transport materials between organelles
Food vacuoles - ANSWER temporarily hold endocytosed food and later fuse with
lysosomes
Central vacuoles - ANSWER Very large in plants and have specialized membrane
called the tonoplast
Function in storage and material breakdown
Storage vacuoles - ANSWER store starches, pigments, and toxic substances
Contractile vacuoles - ANSWER Found in single-called organisms and work to
actively pump out excess water
Endomembrane system - ANSWER Group of organelles and membranes that work
together to modify, package, and transport proteins and lipids that are entering or
exiting a cell
Includes the nucleus, rough and smooth ERs, Golgi apparatus, lysosomes, vacuoles,
and cell membrane
Peroxisomes - ANSWER Perform hydrolysis, break down stored fatty acids, and
help with detoxification
Mitochondria - ANSWER Powerhouse of the cell
Produces ATP for energy use through cellular respiration
, Chloroplasts - ANSWER Found in plants and some protists
Carry out photosynthesis
Centrosomes - ANSWER Organelles found in animal cells containing a pair of
centrioles
Cytoskeleton - ANSWER Provides structure and function within the cytoplasm
Microfilaments - ANSWER Smallest structure of the cytoskeleton, and are
composed of a double helix made of two actin filaments
Cyclosis - ANSWER 'stirring of the cytoplasm'; organelles and vesicles travel on
microfilament "tracks".
Cleavage furrow - ANSWER during cell division, actin microfilaments form
contractile rings that split the cell
Muscle contraction - ANSWER actin microfilaments have directionality, allowing
myosin motor proteins to pull on them for muscle contraction
Intermediate filaments - ANSWER Between microfilaments and microtubules in
size
More stable than microfilaments and mainly help with structural support
Microtubules - ANSWER Largest and give structural integrity to cells
Hollow and have walls made of tubulin protein dimers
Centrioles - ANSWER Hollow cylinders made of nine triplets of microtubules
Centrosomes - ANSWER Contain a pair of centrioles oriented at 90-degree angle
to one another
Extracellular matrix - ANSWER Provides extracellular mechanical support for
cells
Cell walls - ANSWER Carbohydrate-based structures act like a substitute ECM
because they provide structural support to cells that either do not have ECM, or
have minimal ECM
Glycocalyx - ANSWER Glycolipid/glycoproteins coat found mainly on bacterial
Cell membrane - ANSWER Hold cellular components and are mainly composed of
phospholipids, cholesterol, and proteins
Organelles - ANSWER Cellular compartments enclosed by phospholipids bilateral
(membrane-bound)
Are located within the cytosol (aqueous intracellular fluid) and help make up the
cytoplasm
Only eukaryotes contain membrane-bound organelles
Nucleoid - ANSWER Where do prokaryotes keep their genetic material
Nucleus - ANSWER Primarily functions to protect and house DNA
DNA replication and translation occur here
Nucleoplasm - ANSWER Cytoplasm of the nucleus
Nuclear envelope - ANSWER Membrane of the nucleus
Contains two phospholipid bilayers with a perinuclear space in the middle
Nuclear pores - ANSWER Holes in the nuclear envelope that allow molecules to
travel in and out of the nucleus
Nuclear lamina - ANSWER Provides structural support to the nucleus, as well as
regulates DNA and cell division
Nucleolus - ANSWER Dense area that is responsible for making rRNA and
producing ribosomal subunits
Ribosomes - ANSWER Work as small factories that carry out translation
Composed of ribosomal subunits
Rough er - ANSWER Continuous with the outer membrane of the nuclear envelope
,and is "rough" because it has ribosomes embedded in it
Lumen - ANSWER Inside of the rough er
Smooth er - ANSWER Not continuous with other membranes
The main function is to synthesize lipids, produce steroid hormones, and detoxify
cells
Golgi apparatus - ANSWER Made up of cisternae (flattened sacs) that modify and
package substances
Lysosomes - ANSWER Membrane-bound organelles that break down substances
(through hydrolysis) taken in through endocytosis
Transport vacuoles - ANSWER transport materials between organelles
Food vacuoles - ANSWER temporarily hold endocytosed food and later fuse with
lysosomes
Central vacuoles - ANSWER Very large in plants and have specialized membrane
called the tonoplast
Function in storage and material breakdown
Storage vacuoles - ANSWER store starches, pigments, and toxic substances
Contractile vacuoles - ANSWER Found in single-called organisms and work to
actively pump out excess water
Endomembrane system - ANSWER Group of organelles and membranes that work
together to modify, package, and transport proteins and lipids that are entering or
exiting a cell
Includes the nucleus, rough and smooth ERs, Golgi apparatus, lysosomes, vacuoles,
and cell membrane
Peroxisomes - ANSWER Perform hydrolysis, break down stored fatty acids, and
help with detoxification
Mitochondria - ANSWER Powerhouse of the cell
Produces ATP for energy use through cellular respiration
, Chloroplasts - ANSWER Found in plants and some protists
Carry out photosynthesis
Centrosomes - ANSWER Organelles found in animal cells containing a pair of
centrioles
Cytoskeleton - ANSWER Provides structure and function within the cytoplasm
Microfilaments - ANSWER Smallest structure of the cytoskeleton, and are
composed of a double helix made of two actin filaments
Cyclosis - ANSWER 'stirring of the cytoplasm'; organelles and vesicles travel on
microfilament "tracks".
Cleavage furrow - ANSWER during cell division, actin microfilaments form
contractile rings that split the cell
Muscle contraction - ANSWER actin microfilaments have directionality, allowing
myosin motor proteins to pull on them for muscle contraction
Intermediate filaments - ANSWER Between microfilaments and microtubules in
size
More stable than microfilaments and mainly help with structural support
Microtubules - ANSWER Largest and give structural integrity to cells
Hollow and have walls made of tubulin protein dimers
Centrioles - ANSWER Hollow cylinders made of nine triplets of microtubules
Centrosomes - ANSWER Contain a pair of centrioles oriented at 90-degree angle
to one another
Extracellular matrix - ANSWER Provides extracellular mechanical support for
cells
Cell walls - ANSWER Carbohydrate-based structures act like a substitute ECM
because they provide structural support to cells that either do not have ECM, or
have minimal ECM
Glycocalyx - ANSWER Glycolipid/glycoproteins coat found mainly on bacterial
