CALM 2 Flashcards
fundamental units of structure and function – from microorganisms to the most gigantic of all living organisms.
cell
smallest unit that is capable of performing life functions.
cell
Our bodies include more than ___ differentiated cell types that aggregate and interact to form the basic tissues.
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Most cells are ___ cells (body cells) and are said to have two copies of the____ .
somatic ; genome (diploid)
__________which are sperm and egg cells, have one copy of the genome and are haploid.
Germ cells
______are diploid cells that divide to give rise to differentiated cells and replicate themselves in a process called___
Stem cells ; self-renewal.
Cells are composed of
macromolecules.
Provide energy and contribute to cell structure.
Carbohydrates (sugars and starches)
Forms the basis of some hormones, membranes, provides insulation, & stores energy.
Lipids (fats and oils)
Enables blood clotting, forms bulk of connective tissue
Proteins
catalyze biochemical reactions to sustain life.
Enzymes
Translate information from past generations into specific proteins that give a cell its characteristics.
Nucleic Acids (DNA and RNA)
provide specialized functions for the cell.
Organelles
All cell types have a single nucleus, except for ___, which expel their nuclei as they mature.
RBCs
lies between the cell membrane and contains the organelles.
cytoplasm
gelatin-like aqueous fluid that contains salts, mineral and organic molecules.
cytosol
The most prominent organelle of cells
nucleus
genetic headquarter
nucleus
allow specific molecules to move in and out of the nucleus through the envelope.
Nuclear pores
Site of chemical reactions that transfer energy from organic compounds to ATP.
mitochondria
powerhouse of the cel
mitochondria
Has 2 membranes
smooth outer and inner membrane
Boundary between the mitochondria and the cytosol.
smooth outer membrane
Has many folds called Cristae, which enlarge the surface area for more chemical reactions.
inner membrane
folds
cristae
Most numerous and not surrounded by a membrane
Made up of proteins and RNA.
ribosomes
packaged into the ribosomes then transported to the cytosol.
RNA
Protein to be used in the cytosol
free ribosomes
Proteins to be exported or inserted in the cell membrane
ribosomes in ER
System of membranous tubules and sacs
ENDOPLASMIC RETICULUM
molecules move from one part of the cell to another.
ENDOPLASMIC RETICULUM
Covered by ribosomes, prominent in cells that make large amounts of proteins to be exported from the cell.
Rough ER
No ribosomes
Smooth ER
Processing, packaging and secreting organelles.
golgi apparatus
Works closely with ER to modify proteins.
golgi apparatus
Small spherical organelles.
lysosomes
Enclose hydrolytic enzymes within single membranes.
lysosomes
Maintains the shape and size of the cell.
cytoskeleton
Network of long protein strands, not surrounded by a membrane.
cytoskeleton
Small thin threads/ strands of actin (protein).
microfilaments
Largest strands that are hollow tubes; help the cell divide by forming spindle diners that extend across the cell.
microtubules
Hairlike organelles that extend from the surface of the cell.
CILIA & FLAGELLA
Short and present in large numbers.
cilia
Long filaments and less numerous.
flagella
Most prominent structure; maintains its shape with a protein skeleton called the nuclear matrix
nucleus
the site where ribosomes are synthesized; contains RNA to build protein.
nucleolus
Most commonly found in plant cells & bacteria.
Supports and protects cells.
Cell wall
Exclusive in plant cells.
Contains green chlorophyll.
Where photosynthesis takes place.
Chloroplast
Stacks of membrane- enclosed sac.
Golgi apparatus
Sac containing digestive enzymes.
lysosomes
Sac containing enzymes.
peroxisomes
Scaffoid and catalyst for protein synthesis
ribosomes
Releases energy from nutrients, participates in cell death.
mitochondria
Membrane-bound sac
vesicle
Breaks down and detoxifies various molecules.
peroxisome
Temporarily stores or transport substances.
vesicle
Is a bilayer of molecules called ___which forms the structural backbone
phospholipids
A process wherein a series of molecules form pathways that detect signals from outside the cell and transmit them inward.
Signal Transduction
Process wherein the cell membrane helps attach to certain other cells.
Cellular Adhesion
The movement of molecules from a region of high concentration to a region of lower concentration
Diffusion
The diffusion of water across a semipermeable membrane from a weak solution to a strong solution
osmosis
Cell and external solution are at the same concentration
Water entering RBC = water leaving
No change in cell size
isotonic
Cells are placed in a very concentrated (sugar) solution Cells are diluted compared to external solutions & lose water. Cell shrinks (crenation)
hypertomic
Cells are placed in a dilute (sugar) solution
Cell takes up water
Cells swell and finally burst (lyses)
hypotonic
When substances cross the cell membrane against a concentration gradient, using energy and carriers in the membrane.
active transport
Movement of other materials across the cell membrane. Concentration must be higher on one side than the other for there to be movement; imbalance.
passive transport
Moving large molecules across the cell membrane,
facilitated diffusion
Materials enter the cell; cell membrane “pinches in” and forms vesicle inside the cell.
endocytosis
Solid particles are ingested; part of the cell membrane extends around a particle and fuses. Majority of WBCs are phagocytes, responsible for consuming and getting rid of foreign invaders in the body.
phagocytosis
Smaller vesicles;
Contains liquid not particles.
pinocytosis
Materials exit the cell; membrane wrapped particles merge with the cell membrane and are pushed into the external environment.
exocytosis
A meshwork of protein rods and tubules that serves as the cell’s architecture, positioning organelles overall providing 3D shape.
cytoskeleton
3 major types of elements:
Microtubules,
Microfilaments, and
Intermediate filaments
which include bacteria, blue-green algae, spirochetes, rickettsia and mycoplasma organisms, are very small living cells that reproduce asexually by a process that does not involve mitosis.
Prokaryotes
They have no membranes, except the cell membrane and no cytoplasmic organelles such as vacuoles, mitochondria, endoplasmic reticulum or photosynthetic plastids
prokaryotes
Cocci
round
Bacilli
rods
Spirilla or Spirochetes
helical cells
have a single chromosome consisting of a tightly coiled molecule of deoxyribonucleic acid that is not associated with protein and is not separated from the cytoplasm by a membrane.
prokaryotes
make up organisms from the protists, fungi, plant and animal kingdoms.
Eukaryotic cells
is any life form consisting of one or more cells that contain a membrane-bound nucleus and organelles separate from the plasma membrane enveloping the cell
eukaryote or eukaryote
Cells of higher plants and animals
eukaryotic
Cells of this type are larger and more complex
eukaryotic
have a true nucleus containing the DNA as well as various other membrane-bound organelles. These include mitochondria, the rough and smooth endoplasmic reticulum, and the nucleus.
eukaryotic
ordinarily larger (10 – 100um)
eukaryotic
1 – 10um
prokaryotic
multicellular
Eukaryotes
unicellular
prokaryotes
undergo sexual reproduction
Eukaryotes
reproduce asexually
prokaryotes
occurs by mitosis
Eukaryotes
binary fission
prokaryotes
this process does not involve the nuclear envelope and centromere and spindle formation.
binary fission
a form of cell death.
apoptosis
Series of events which describes the sequence of activities as a cell prepares to divide and then does
Cell Cycle
not dividing
interphase
dividing
mitosis
a cell duplicates its chromosomes
mitosis
it apportions one set of chromosomes into each of two resulting cells, called daughter cells.
cytokinesis
produces sperm or eggs, which have half the amount of genetic material in somatic cells, as 23 single chromosomes.
meiosis
a cell continues the basic biochemical functions of life while replicating its DNA and other subcellular structures.
interphase
Interphase is divided into two gap phases
(G1 and G2) & one synthesis phase (S).
is the period of the cell cycle that varies the most in duration among different cell types. Slowly dividing cells, like liver cells, may exit at G1 & enter G0 where they remain for years.
G1
the cell replicates its entire genome. As a result, each chromosome then consists of two copies joined at an area called the centromere. In most human cells, the ___takes 8-10 hours.
S phase
will pull the chromosomes apart.
mitotic spindle
Microtubules form structures called __ near the nucleus.
centrioles
Centriole microtubules join with other proteins and are oriented at right angles to each other, forming paired, oblong structures called ___that organize other microtubules into the spindle.
centrosomes
The 2 long strands of identical chromosomal material in a replicated chromosome are called___
chromatids,
Temporarily pauses the cell cycle while special proteins repair damaged DNA.
DNA damage checkpoint
Turns on as mitosis begins. Proteins called survivins override signals telling the cell to die, ensuring that mitosis (division) rather than apoptosis (death) occurs.
Apoptosis checkpoint
Oversees construction of the spindle & the binding of chromosomes to it.
Spindle assembly checkpoint
Cells know how many divisions remain through the chromosome tips
telomeres
function like cellular fuses that burn down as pieces are lost from the ends. At each mitosis, ____ lose bases, gradually shortening the chromosome.
Telomeres
keeps chromosome tips long
telomerase
rapidly & neatly dismantles a cell into membrane-enclosed pieces that a phagocyte (a cell that engulfs and destroys another) can mop up.
apoptosis
also a continuous process.
apoptosis
Within seconds, enzymes called ___are activated inside the doomed cell, stimulating each other and snipping apart various cell components.
caspases
renew tissues so that as the body grows, or loses cells to apoptosis, injury, and disease, other cells are produced that take their places.
stem cells and progenitor cells
produces progenitors whose daughter cells are specialized blood cells.
hematopoietic stem cell in bone marrow
its ability to continue the lineage of cells that can divide to give rise to another cell like itself
Self-renewal
Which means it can give rise to every cell type, including the cells of the membranes that support the embryo.
Totipotent
Their daughter cells have fewer possible fates.
Pluripotent
Daughter cells have only a few developmental choices.
multipotent
which follows mitosis, the cell resumes synthesis of biomolecules which contribute to building the extra plasma membrane required to surround the two new cells that form from the original one.
G1
contains only a “nucleoid” where DNA is located
prokaryotess
Which phase during the cell cycle is a cell’s DNA replicated?
s-phase
During which stage of mitosis do the centromeres split?
anaphase
Which of the following organelles aids in the production of proteins?
-Ribosomes
Which of the following is NOT a function of the plasma membrane?
-Regulates the flow of materials in and out of the cell
When during the cell cycle are chromosomes visible?
-Only during cell division
