Animal Tissues Flashcards
What is a cell?
The basic unit of life.
What is tissue?
A group of similar cells performing a similar function.
What are organs?
A number of similar tissues.
What is a system?
A number of different organs.
What is an organism?
A number of systems that work together.
What is cell differentiation?
Cells that take on different functions.
How many groups are mammalian tissues classified into? Name them.
Four.
- Epithelial
- Connective
- Muscle
- Nerve
Name the four simple epithelium.
- Squamous
- Cuboidal
- Ciliated columnar
- Columnar
What are stem cells?
Undifferentiated cells. (cells without functions)
Where is squamous tissue found?
-Found in the walls of alveoli and blood vessels. (endothelium)
What is the function of squamous tissue?
- Creates a large surface area for CO2 + O2 to pass through easier.
- Easy movement.
- Reduces friction between blood and walls of blood.
What is the structure of squamous tissue?
-A single layer of thin flat cells which interlock tightly.
Where is cuboidal tissue found?
-Lines glands and walls of tubes in the kidney.
What is the function of cuboidal tissue?
- Secretion.
- Absorption of water back into the blood.
- Absorption in the kidneys.
What is the structure of cuboidal tissue?
- Appear cube shaped.
- Round nucleus in the centre of the cell.
- Tightly packed.
Where is ciliated columnar tissue found?
- Found in air passages such as the nose, trachea, bronchi.
- Also found in the fallopian tubes.
What is the function of ciliated columnar tissue?
- Cilia move in waves to move the mucus with the dust upwards away from the
lungs. Goblet cells secrete mucus to trap dust. - In fallopian tubes cilia + mucus propel the ovum to the uterus.
What is the structure of ciliated columnar tissue?
- Have cilia on free surface.
- Columnar in shape.
- Goblet cells may be present.
Where is columnar tissue?
-Lines the digestive system from the stomach to the anus.
What is the function of columnar tissue?
-In small intestines they aid in the movement or absorption of water, food, salts +
vitamins.
-Goblet cells secrete protective mucus in the digestive system.
What is the structure of columnar tissue.
- Elongated, large cells with an oval shaped nucleus near the base.
- Goblet cells may be present.
Where is compound epithelium found?
-Forms the epidermis of the skin and lines of the oesophagus.
What is the structure of compound epithelium?
-Innermost layer has cells that divide actively to replace dead cells.
-Uppermost layer of cells are dead and flattened and are continually rubbed off by
friction.
What is the function of compound epithelial tissues?
- Protective function:
- against mechanical injuries.
- desiccation. (drying out)
- entry of bacteria.
Name the six different types of connective tissues.
- Areolar
- Yellow elastic
- White fibrous
- Blood
- Bone
- Cartilage
Where is areolar tissue found?
- Found as a continuous layer.
- Fills spaces between organs and muscles.
What is the structure of areolar tissue?
-Made up of a jelly-like matrix
-With large fibroblasts which synthesize 2 types of fibres:
1. collagen (white + non elastic) fibres
2. yellow elastic fibres
Contain:
-mast cells
-adipocytes (fat cells)
-macrophages
What is the function of areolar tissues?
- Connects layers of skin.
- Supports + protects organs + muscles.
- Collagen fibres provide strength + yellow fibres allow stretching.
- Mast cells secrete matrix, adipocytes store fat, macrophages provide protection against infection.
Where is white fibrous tissue found?
-In the tendons to join muscle.
What is the structure of white fibrous tissue?
- Consists of a dense network of white collagen fibres which make it strong.
- The matrix is jelly-like.
What is the function of the white fibrous tissue?
-They are very strong so that muscles can pull on the bones to cause movement.
Where is yellow elastic tissue found?
-In the ligaments to join bones to bone at the joints.
What is the structure of yellow elastic tissue?
- Consists of a dense network of yellow elastic fibres.
- the matrix is jelly-like.
Where is blood found? (only connective tissue which is fluid)
-Found in a closed blood system consisting of heart, blood vessels and capillaries.
What is the structure of blood?
- Red blood cells/Erythrocytes, don’t have a nucleus, made in red bone marrow, short lifespan, pigment called haemaglobin which carries CO2 + O2, biconcave discs; allows a larger surface area to volume ratio.
- White blood cells/Leucocytes, produced in red bone marrow and in the lymph nodes, have one or more nuclei present, can move around like amoeba,
- Platelets/Thrombocytes, produced in bone marrow and are cell fragments with no nucleus.
- Plasma, has a white/yellowish colour, mainly water with many substances dissolved in it e.g. glucose, amino acids + CO2.
What is the function of blood?
- Erythrocytes have haemaglobin which carries O2 + CO2.
- Leucocytes fight infection and engulf any dead cells, produce antibodies to
destroy pathogens. - Platelets are involved in the clotting of blood which prevents excessive
bleeding. - Plasma transports dissolved substances such as nutrients, gases, hormones,
throughout the body.
Where is bone found?
-In the endoskeleton of humans.
What are bone cells called and lie in what fluid filled cavities?
Bone cells are osteocytes and lie in cavities called lacunae.
What is the function of bone?
-Osteocytes secrete minerals such as calcium phosphate to make bone hard.
-The endoskeleton protects internal organs, gives the body shape and support,
and allows movement.
Where is cartilage found?
-Found on the tip of the nose, in the ear and forms the epiglottis.
Where is white fibrous cartilage found?
-Between discs of vertebrae.
What is cartilage made up of?
-Made up of cells called chondrocytes and fibres that are found in a rubbery ground matrix called chondrin.
Where is hyaline cartilage found?
- Found at the ends of bones at moveable joints;
- Between the ribs and sternum.
- Forms C-shaped rings in the trachea.
What is the structure of white fibrous cartilage?
-Has thick collagen fibres in the matrix. (very strong)
Where is yellow elastic collagen found?
-Tip of the nose and ear and forms the epiglottis.
What is the structure of yellow elastic fibres?
-Many yellow elastic fibres which bend easily without breaking.
What is the function of hyaline cartilage?
- To prevent damage between joints and bones.
- Connects ribs to the sternum.
- Keeps the trachea open at all times.
What is the function of white cartilage?
-White cartilage is tough and flexible to provide cushioning between vertebrae to absorb shock.
What is the function of yellow cartilage?
- Gives shape and allows bending of ear + nose.
- The epiglottis keeps the trachea closed during swallowing.
What are the three types of muscle tissue?
- voluntary/skeletal
- involuntary/smooth
- cardiac
Where is skeletal muscle tissue found and what is its structure?
- Always attached to the bones of skeleton.
- Made of long striped muscle fibres. (eac muscle fibre has a nuclei)
What is the function of skeletal muscle tissue?
- Moves joints.
- Allows voluntary movements. (walking, running)
- Contract quickly and strongly and get easily tired.
Where is involuntary/smooth muscle tissue found and what is its structure?
- Found in blood vessels, walls of the gut, bladder
- They are thin and short with no striations. (spindle shaped, one nucleus per fibre)
What is the function of involuntary/smooth muscle tissue?
- Not controlled by will thus it is responsible for automatic movements in the body such as dilation and constriction of blood vessels.
- Does not tire.
Where are cardiac muscle tissues found and what are their structure?
- Only found in the heart walls.
- Striated, one spherical nucleus per fibre
- Fibres are branched.
What is the function of cardiac muscle tissues?
- Responsible for involuntary movements of the heart.
- Does not tire easily and is strong.
Name the three types of nerve tissues.
- Inter-neurons
- Motor neurons
- Sensory neurons
What is the structure of nerve cells?
- Consists of millions of nerve cells/neurons which consist of :
1. Dendrites which are outgrowths or processes. They are highly branched and lead to a:
2. cell body with cytoplasm and nucleus.
3. Axons are ingle long processes often covered by fatty tissue called a…
4. Myelin sheath which insulates, protects and speeds up the transmission of the nerve impulse.
5. A synapse is a microscopic gap between successive neurons where the impulse “jumps” from one neuron to the next.
What is the function of nerve tissue?
- keeps different parts of the body in contact so that they can all work together.
- neurons monitor changes that happen inside and outside the body; the processes the info and responds.
Sensory nrn. carry nerve impulses from receptors to the central nervous system.
Motor nrn. carry nerve impulses from the c.n.s to the effector (muscle/gland).
Inter-nrn. are found in the c.n.s and connect sensory nrn. to motor nrn.
What is the tissue found covering or lining organs?
Epithelial tissues.
Strong, white fibres found in connective tissue.
Collagen.
The extra-cellular substance found in connective tissues.
Matrix.
Hairs found on specific epithelial cells
Cilia
The type of epithelium found making the walls of alveoli
Squamous
Epithelial cells specialized to produce mucus
Goblet cells
Tissue connecting skin to underlying tissue
Areolar tissue.
Bone cells
Osteocytes
Cartilage cells
Chondrocytes
Connective tissue joining muscle to bone
Tendns
Epithelium lining kidney tubules.
Cuboidal
The layer on which epithelial cells rest.
Basement membrane
The protein making up the yellow, elastic fibres in ligaments.
Elastin.
The type of cartilage covering the end of bones.
Hyaline
The type of cartilage forming the tip of the nose
Yellow elastic
Bone cells are arranged in rings called?
Lamellae
Fluid filled spaces containing bone or cartilage cells.
Lacunae
Tiny interconnecting canals found in bone.
Haversian canals
Cells that store fat.
Adipocytes
Red blood cells
Erythrocytes
The liquid part of the blood
Plasma
The muscle type which allows for voluntary movements:
Skeletal
The type of muscle tissue making up the heart:
Cardiac
The small gap between nerve cells.
Synapse
Neurons that transmit impulses to the brain/spinal cord .
Sensory
The fatty layer around neuron axons:
Myelin sheath
The type of leucocyte that produces antibodies:
White blood cells.
The blood component responsible for clotting:
Platelets
The red pigment found in red blood cells
Haemoglobin.
