Cells tissues and blood composition Flashcards
Cells are often called
the microscopic building blocks of the human body
They are active and dynamic
they continually grow ad specialise, function, die and replenish themselves by the millions every second
The whole body contains
about 37.2 trillion cells
There are
226 different kinds of cells
The cell
provide structure for the body
take in nutrients form food
convert those nutrient into energy
carry out specialised functions
contain then body’s hereditary material in the form of DNA and make copies of themselves
the cell is the basic unit of life
Most of our cells have three main parts
cell membrane
mitochondria
nucleus
The cell membrane
selectively permeable (it only lets certain molecules enter and exit and it controls the amount substances that go into or out of the cell)
The mitochondria
present in nearly all human cell types (powerhouse of the cell) are vital to our survival. They generate the majority of energy from food we ingest
1. Energy production
2. Cell death
3. Storing calcium
4. Heat production
The nucleus
the cells control centre
as it encloses the genetic material, which contains the information that specifies all the cell activity
Cell types found in the human body
Red blood cells (RBC)
Epithelial cells
Adipose (fat) cells
Red blood cells (RBC)
Unlike other cells, red blood cells lack a nucleus and organelles. instead, they have an oxygen carrying protein (Hemoglobin). which gives blood its red colour
Epithelial cells
The skin cells and the cells lining the lungs and reproductive tracts are among the barrier cells, called epithelial cells, which line the cavities and surfaces of the body
Adipose (fat) cells
These cells are highly adapted for storing fat. the bulk of their interior is taken up by a large droplet or semi-liquid fat. when we gain weight, they fill up with more fat.
Nerve cells
these electrically excitable cells transmit electrical signals down an extended set called an axon. Found throughout the body, they enable s to feel sensations
Smooth muscle cells
one of three types of muscle cell, smooth muscle cells are spindle-shaped cells found in the arteries and the digestive tract that produce contractions
Ovum (egg) cells
The largest cells in the female human body, eggs are female reproductive cells, like sperm they have just 3 chromosome
tissue
group of ells working together with a common function
organ
group of tissues working together with a common function
system
group of organs working together with a common function
organism
can be made by only one cells or many organ systems
Tissue types
- Connective
- Epithelial
- Muscle
- Nervous
Connective
fat and other soft padding tissue
bone
tendon
Epithelial
Lining of GI tract organs and other hollow organs
skin surface (epidermis)
Muscle
cardiac muscle
smooth muscle
skeletal muscle
