Anatomy Ch 3 Test Flashcards
the basic unit of structure and function in organisms
cell
in 1665, who discovered cells
Robert hooke
who invented the complex microscope
Antony van leeuwenhoek
cell theory:
1) all organisms are made up of one or more cells
2) cells are the basic unit of structure and function of all organisms
3) all cells come from other cells that already exist
what type of cell will be directly affected by a cell or virus getting in?
prokaryotic
cells without a nucleus or membrane bound organelles
prokaryotic
cells with a nucleus and membrane bound organelles
eukaryotic
cells come in all different _______ and _______
sizes and shapes
different tissues contain cells with different sizes and shapes for ___________ purposes
functional
a molecule that specifically binds to a receptor protein on a cell’s plasma membrane
ligand
examples of ligands
hormones, neurotransmitters, nutrients, enzymes, ions, antibodies
all of the examples of ligands are…
chemicals
main structures of a cell:
1) plasma membrane - also called cell membrane
2) nucleus
3) cytoplasm/organelles
is the cytoplasm a structure?
no
plasma membrane functions
protection - serves as a barrier from outside of the cell
semi permeable - allows only certain molecules to enter or exit
communication - allows cells to talk to their surroundings
plasma membrane composition:
lipid (phospholipids)
proteins
carbohydrates
some cholesterol
phospholipid molecules: (in the plasma membrane) have a double layer that acts as the __________ for the cell
barrier
what all do phospholipid molecules allow through
allows oxygen, carbon dioxide, steroids to enter and exit but few other molecules can get through this layer
Cell surface proteins (3):
a. Marker protein - identifies the cell
b. Channel protein - allows specific molecules to enter & exit
c. Receptor protein - allows cells to communicate
__________ is a name given to cell surface proteins that extend through the lipid bilayer and may protrude from one or both sides of the cell membrane
integral protein
the area inside the cell surround the nucleus
cytoplasm
the __________ are found in the cytoplasm of the cell
organelles
there is a fluid in the cytoplasm called ___________
cytosol
contains the DNA and an organelle called the nucleolus
nucleus
The nucleolus produces…
ribosomes
The nucleus us enclosed by the __________
nuclear membrane
The nuclear membrane acts just like the ________ of the cell, and has the same composition as the _________
plasma membrane, plasma membrane
True or False: Every structure in your body is made of proteins
True
two main/primary compositions of plasma membrane
lipids and proteins
big, spherical structure found inside the nucleus; contains DNA
nucelolus
cells have many __________ __________ that work together to perform the necessary functions for life
compartmentalized organelles
the first signs of amytrophic lateral shclerosis, also known as _____________ diseases, are subtle - a foot drages, clothing feels heavy on the body, or an exercise usually done with ease becomes difficult. Usually within _____ years of noticing these first signs, failure of the _________ that stimulate muscles becomes so widespread that breathing unaided becomes impossible.
Lou Gehrig’s; five; motor neurons;
ALS currently has no treatment. part of the reason is that neurons do not _______, so they are difficult to grow in the lab in order to test a new drug.
divide
To treat ALS, potentially, a technology called __________ can take a specialized cell type back to a stage in which it can specialize in any of several ways.
cellular reprogramming
_______ is a group of closely related diseases that can affect many different organs
cancer
the lifetime risk of developing cancer is _____ for males and _____ for females
1 in 2; 1 in 3
Cancer results from ________ that alter the cell cycle in __________
mutations; somatic cells
5 characteristics cancer shares
hyperplasia; dedifferentiation; invasiveness; angiogenesis; metastasis
hyperplasia is __________-
uncontrolled cell division
dedifferentiation is ____________
loss of the specialized structures and functions of the normal type of cell from which the cancer cells descend
invasiveness is ________
the ability of cancer cells to break through boundaries
angiogenesis is ___________
the ability of cancer cells to induce extension of nearby blood vessels
metastasis is _________
the spread of cancer cells to other tissues through the bloodstream or lymphatic system
_________ are small structures in a cell that perform specific functions to keep the cell in homeostasis
organelles
list the functions, shape, general location in cell, and any special notes about: nucleus
functions: contains DNA; Controls cell growth and reproduction; regulates gene expression
shape: generally spherical or oval
general location: central part of the cell (typically in eukaryotic)
special notes: surrounded by a double membrane; contains nucleoplasm and nucleolus where ribosome synthesis occurs
list the functions, shape, general location in cell, and any special notes about:
Functions:
Synthesizes ribosomal RNA (rRNA)
Assembles ribosomal subunits
Shape:
Generally round or irregular
General Location:
Within the nucleus
Special Notes:
Not membrane-bound
Visible during interphase as a dense region in the nucleus
brief brief brief list the functions, shape, general location in cell, and any special notes about: nuclear membrane
Functions:
Encloses the nucleus
Regulates the transport of molecules in and out of the nucleus
Shape:
Double-layered membrane
General Location:
Surrounds the nucleus
Special Notes:
Composed of inner and outer lipid bilayers
Contains nuclear pores for selective transport
brief brief brief list the functions, shape, general location in cell, and any special notes about: ribosomes
Ribosomes
Functions:
Synthesizes proteins by translating mRNA
Shape:
Small, round structures (subunits)
General Location:
Free in the cytoplasm or attached to the endoplasmic reticulum (rough ER)
Special Notes:
Composed of rRNA and proteins
Present in both prokaryotic and eukaryotic cells
brief brief brief list the functions, shape, general location in cell, and any special notes about: mitochondria
Functions:
Produces ATP through cellular respiration
Regulates metabolic processes
Shape:
Rod-shaped or oval
General Location:
Scattered throughout the cytoplasm
Special Notes:
Has a double membrane (inner and outer)
Contains its own DNA and ribosomes, enabling some independent replication
brief brief brief list the functions, shape, general location in cell, and any special notes about: lysosomes
Functions:
Digests and breaks down waste materials and cellular debris
Contains digestive enzymes
Shape:
Spherical or oval
General Location:
Scattered throughout the cytoplasm
Special Notes:
Often referred to as the cell’s “clean-up crew”
Plays a role in autophagy (removal of damaged organelles)
brief brief brief list the functions, shape, general location in cell, and any special notes about: vacuoles
Functions:
Storage of substances (water, nutrients, waste)
Helps maintain turgor pressure in plant cells
Shape:
Generally large and membrane-bound; can vary in shape
General Location:
Predominantly in the cytoplasm; larger in plant cells
Special Notes:
Plant cells often have a central vacuole, while animal cells may have smaller vacuoles
Involved in cellular metabolism and maintaining pH balance
brief brief brief list the functions, shape, general location in cell, and any special notes about: endoplasmic reticulum
Functions:
Synthesizes proteins (rough ER) and lipids (smooth ER)
Detoxifies harmful substances
Shape:
Network of membrane-bound tubules and sacs
General Location:
Adjacent to the nucleus and throughout the cytoplasm
Special Notes:
Rough ER has ribosomes on its surface; smooth ER does not
Plays a role in intracellular transport and processing of biomolecules
brief brief brief list the functions, shape, general location in cell, and any special notes about: microtubules and microfilaments
Microtubules
Functions:
Provides structural support
Aids in cell division and intracellular transport
Shape:
Hollow, tube-like structures
General Location:
Throughout the cytoplasm, forming part of the cytoskeleton
Special Notes:
Composed of tubulin protein subunits
Involved in forming the mitotic spindle during cell division
Microfilaments
Functions:
Supports cell shape
Facilitates cell movement and muscle contraction
Shape:
Thin, thread-like structures
General Location:
Throughout the cytoplasm, also part of the cytoskeleton
Special Notes:
Composed of actin protein subunits
Plays a role in cytokinesis and cell motility
brief brief brief list the functions, shape, general location in cell, and any special notes about: cilia
Functions:
Move fluids and particles across the cell surface
Assist in locomotion for certain cells
Shape:
Short, hair-like projections
General Location:
Found on the surface of some eukaryotic cells
Special Notes:
Composed of microtubules arranged in a “9+2” structure
Involved in sensory functions and can be found in respiratory tract and reproductive organs
brief brief brief list the functions, shape, general location in cell, and any special notes about: flagella
Functions:
Propel cells through liquid environments
Aid in cell motility
Shape:
Long, whip-like projections
General Location:
Found on the surface of certain cells, such as sperm
Special Notes:
Composed of microtubules arranged in a “9+2” structure
Typically fewer in number than cilia and longer in length
brief brief brief list the functions, shape, general location in cell, and any special notes about: vesicles
Functions:
Transport materials within the cell
Store substances and facilitate metabolism
Shape:
Small, membrane-bound sacs
General Location:
Scattered throughout the cytoplasm
Special Notes:
Can originate from the endoplasmic reticulum or Golgi apparatus
Involved in processes like exocytosis and endocytosis
brief brief brief list the functions, shape, general location in cell, and any special notes about: centrosome
Functions:
Organizes microtubules
Plays a key role in cell division (spindle formation)
Shape:
Typically cylindrical structure
General Location:
Near the nucleus in the cytoplasm
Special Notes:
Composed of a pair of centrioles surrounded by pericentriolar material
Important for maintaining cell structure and facilitating mitosis
brief brief brief list the functions, shape, general location in cell, and any special notes about: chromatin
Functions:
Packages DNA to fit in the nucleus
Regulates gene expression and DNA replication
Shape:
Fibrous and thread-like structure
General Location:
Found within the nucleus
Special Notes:
Composed of DNA and proteins (histones)
Exists in two forms: euchromatin (active) and heterochromatin (inactive)