Visua of the Human Body

Cell and tissues
The human body is formed of hierarchically organized components (tissues, organs,
and systems), of which the basic unit is the cell. Cells are the site of intense activity:
they accumulate and transmit energy, make proteins that are essential to the body’s
functioning, and constantly reproduce by cellular division. They also contain all of the
genes belonging to each individual.
human cell
célula F humana
Basic unit of the human body, whose size and shape vary depending on the functions that it performs.
structure of a cell
estructura F de la célula F
CELL AND TISSUES
All human cells have a similar structure:
they are formed of a nucleus surrounded
by cytoplasm and encased in a
membrane.
cell nucleus
núcleo M celular
Central core of the cell containing
genetic information in the form of DNA
and guiding protein synthesis.
cytoplasm
citoplasma M
Liquid substance forming the inside of
the cell, around the nucleus, in which
cellular organelles bathe.
endoplasmic reticulum
retículo M endoplásmico
Cell structure consisting of a network of
pockets surrounding the nucleus; it is
involved in protein synthesis.
Golgi apparatus
aparato M de Golgi
Cell structure consisting of a group of
membrane sacs; it is involved in the
transport and maturation of proteins in
the cell.
microfilament
microfilamento M
Rod-shaped structure supporting the
cell and giving it its shape.
centriole
centríolo M
Cell structure playing a key role during
mitosis.
vacuole
vacuola F
Spherical cavity in which water, waste
and various substances required by the
cell are stored.
mitochondrion
mitocondria F
Structure associated with cell
breathing; it produces and stores
energy in the cell.
pseudopod
pseudópodo M
Extension of the cytoplasm of
certain cells, serving mainly in cell
displacement.
ribosome
ribosoma M
Organelle, floating free or bound to
the endoplasmic reticulum, producing
proteins essential to the formation and
functioning of the human body.
cell membrane
membrana F celular
microtubule
microtúbulo M
Cylindrical structure supporting the
cell and allowing organelles and
substances in the cell to move about.
Bilayer of lipid molecules forming the
outer surface of the cell.
lipids
lípidos M
Molecules containing fatty acids,
making up the cell membrane.
The Life of Cells
Each human being is composed of more than
50 trillion cells. Hundreds of millions of them die
every minute, and just as many are born through
cellular division. Some, such as certain white
blood cells, die after only a few hours, while
others, such as neurons, may survive throughout
a human being's life.
protein
proteína F
Organic compound formed of amino
acids; in the cell membrane, proteins
form channels allowing the exchange
of substances with the outside
environment.
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human cell
cell nucleus
núcleo M celular
Central core of the cell containing genetic
information in the form of DNA and
guiding protein synthesis.
chromatin
cromatina F
Substance consisting of proteins and
DNA contained in the nucleus; it is
compressed into chromosomes during
mitosis.
nucleoplasm
nucleoplasma M
Liquid substance forming the inside
of the nucleus of a cell and in which
especially chromatin and nucleoli
bathe.
CELL AND TISSUES
nuclear envelope
envoltura F nuclear
Membrane surrounding the nucleus.
nucleolus
nucléolo M
Spherical body located inside the
nucleus and playing a role in the
synthesis of ribosomes.
examples of cells
ejemplos M de células F
The human body has about 200 types of cells, having very different characteristics and
appearance depending on the functions that they perform in the organism.
ovum
óvulo M
spermatozoon
espermatozoide M
muscle fiber
fibra F muscular
Mature female reproductive cell
produced by the ovary; after fertilization
by a spermatozoon, it enables an embryo
to develop.
Mature and mobile male reproductive
cell produced by the testis; the main
constituent of sperm, its purpose is to
fertilize the ovum.
Contractile cell, constituent element of
muscles.
osteocyte
osteocito M
chondrocyte
condrocito M
fat cell
adipocito M
Mature cell, constituent element of bone
tissue.
Cell, constituent element of cartilage.
Cell forming the essential component
of adipose tissue and ensuring the
synthesis, storage and release of lipids.
photoreceptor
fotorreceptor M
neuron
neurona F
white blood cell
glóbulo M blanco
red blood cell
glóbulo M rojo
Cell found in the retina capable of
capturing light rays and translating them
into nerve signals.
Cell of the nervous system allowing
information to be carried in the form of
electrical and chemical signals.
Blood cell belonging to the immune
system, thus playing an essential role in
the body’s defenses.
Blood cell that carries oxygen from the
lungs to the tissues and carbon dioxide
from the tissues to the lungs.
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tissue
tejido M
All the cells that have a similar structure and perform similar or complementary functions. Four main cell types make up the frame of the
organism: epithelial, connective, muscle and nervous.
CELL AND TISSUES
epithelium
tejido M epitelial
microvillus
microvellosidad F
Protrusion of the cell membrane that
increases its surface.
Tissue formed of cells organized in
layers; it serves covering, secretory and
protective functions.
basal lamina
lámina F basal
Extracellular matrix anchoring epithelial
cells to adjacent tissue.
epithelial cell
célula F epitelial
Cell component of epithelial tissue.
examples of epithelia
ejemplos M de tejidos M epiteliales
They include tissues that form the covering of all body
surfaces and line inner cavities (mucous membranes,
endothelia, epidermis), and glandular tissues that have
secretory functions.
exocrine gland
glándula F exocrina
All secretory cells producing secretions
released outside the body; they consist
especially of salivary and sweat glands.
excretory duct
canal M excretor
Duct carrying secretions from the
exocrine gland.
secretory cell
célula F secretora
Epithelial cell specialized in the
secretion of various substances useful
to the body.
mucous membrane
mucosa F
Damp epithelial tissue lining an
open cavity of the body; the mucous
membrane plays a role in absorption and
secretion (mucus).
epithelium
tejido M epitelial
Tissue formed of cells organized in
layers; it serves covering, secretory and
protective functions.
mucous gland
glándula F mucosa
Exocrine gland that secretes mainly
mucus.
mucus
mucosidad F
Translucent viscous substance secreted
by the mucous membrane and that
plays a protective role.
mucous cell
célula F calciforme
Epithelial cell that secretes mucus.
chorion
corion M
Loose connective tissue beneath
the epithelial tissue of the mucous
membrane.
muscularis mucosae
mucosa F muscular
Fine layer of smooth tissue beneath the
chorion.
submucosa
submucosa F
Connective tissue beneath the mucous
membrane.
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tissue
fibrous tissue
tejido M fibroso
Connective tissue characterized by an
abundance of collagen fibers; it forms
especially the tendons and ligaments.
examples of connective tissues
ejemplos M de tejidos M conjuntivos
Connective tissue: tissue made up of relatively few cells and fibers bathed
in a more or less abundant fluid; its functions are to support, protect and
fill in spaces.
CELL AND TISSUES
adipose tissue
tejido M adiposo
Connective tissue made up essentially of
adipocytes; it is the body’s energy reserve.
cartilage
tejido M cartilaginoso
Connective tissue consisting of cells encased
in a rigid substance; it covers the articular
surfaces of bones and forms certain soft parts
of the body.
The Most Abundant
elastic tissue
tejido M elástico
Connective tissue made up predominantly of
elastic fibers; it is found especially in certain
ligaments and in the walls of the arteries,
trachea and vocal chords.
Connective tissue, present in all organs,
is the most abundant tissue in the human
body: it accounts for two thirds of the total
volume of tissue.
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mitosis
mitosis F
All the mechanisms of cell division that allow the formation of two identical daughter cells from a mother cell.
CELL AND TISSUES
prophase
profase F
First stage of mitosis, during which the
chromatin condenses into chromosomes;
the two pairs of centrioles move toward
opposite poles.
interphase
interfase F
metaphase
metafase F
Period between two successive cell
divisions, during which the cell grows.
Second stage of mitosis, during which the
chromosomes align in the middle of the
cell, guided by the mitotic spindle; the
nuclear membrane disaggregates.
chromosomes
cromosomas M
Elements of the nucleus of a cell, made up
of DNA and proteins and carrying genetic
information; they are observed only during
cell division.
centrioles
centriolos M
Double cellular structures that
duplicate during interphase.
mitotic spindle
huso M mitótico
Ephemeral cellular structure joining the
two pairs of centrioles during mitosis.
cytokinesis
citocinesis F
anaphase
anafase F
Stage of mitosis during which the
cytoplasm separates in two; the original
cell (or mother cell) is replaced by two
identical daughter cells.
Third stage of mitosis, during which the
chromosomes separate into chromatids
and move to either of the cell’s poles.
telophase
telofase F
Fourth stage of mitosis, during which the
chromosomes reassume the appearance
of the chromatin; a new nuclear envelope
appears to cordon off the two nuclei.
chromatid
cromátida F
One of the two strands of a chromosome.
cytoplasm
citoplasma M
Gel-like substance forming the inside of
the cell, around the cell nucleus.
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DNA
ADN M
Complex molecule containing the genetic characteristics (genes) of every person.
DNA molecule
molécula F de ADN M
Billions of Copies
adenine
adenina F
Complementary nitrogenous base of
thymine.
thymine
timina F
Complementary nitrogenous base of
adenine.
nucleotide
nucleótido M
cytosine
citosina F
Complementary nitrogenous base of
guanine.
Basic unit of DNA molecules, consisting
of a nitrogenous base.
guanine
guanina F
Complementary nitrogenous base of
cytosine.
nitrogenous base
base F nitrogenada
Small constituent molecule of a nucleotide;
there are four types that assemble in the DNA
molecule to form a sequence specific to each
individual.
chromosomes
cromosomas M
Elements of the nucleus of a cell, made up
of DNA and proteins and carrying genetic
information; they are observed only during
cell division.
autosome
autosoma M
Chromosome that carries hereditary
characteristics unrelated to sex.
sex chromosomes
cromosomas M sexuales
Chromosomes responsible for
determining sex.
centromere
centrómero M
Short section of a chromosome that
holds the two chromatids together.
X chromosome
cromosoma M X
Sex chromosome present in both men
and women.
Y chromosome
cromosoma M Y
Sex chromosome present only in men.
chromatid
cromátida F
One of two strands of a chromosome, consisting of
a short arm and a long arm; during cell division, the
two chromatids separate at the centromere.
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CELL AND TISSUES
The DNA molecule appears in the shape
of a double helix made up of billions of
nucleotides; it is the largest molecule in
the human body.
The human genetic heritage is included in
46 chromosomes (22 pairs of autosomes and
1 pair of sex chromosomes). Each cell in the body
has its own copy: for example, a skin cell contains
the instruction for eye color.