Cells Flashcards
Cranial Cavity contains:
- the brain
- meninges (the covering)
- spinal cord
Where does the spinal cord run?
from the brain down through vertebral column within the spinal cavity
Thoracic Cavity contains:
- heart
- lungs
Abdominal Cavity (from front) contains:
- liver
- gall bladder
- stomach
- small intestine
- large intestine
What are the Thoracic and Abdominal cavities separated by?
The diaphragm
Abdominal Cavity (from back) contains:
- spleen
- kidneys
- pancreas
- large blood vessels
Pelvic Cavity contains:
- bladder
- urethra
- bowel
- female = ovaries, uterus, vagina
What are the two types of cells? (not all found in the human body)
1 - Eukaryotes
2 - Prokaryotes
Eukaryotes contains:
membrane bound organelles such as nucleus.
Examples of eukaryote cells:
- human cells
- plant cells
- fungi
What do Prokaryotes cells not contain? example?
They are cells that do not contain a nucleus or membrane bound organelle.
ie. bacteria
What two types of cells does the human body contain?
1 - somatic - body cell
2 - germ - sex cell
What does a somatic cells contain?
46 chromosomes
What does a germ cell contain?
23 chromosomes
- sperm in male
- ovum in female
What does a chromosome do?
Carries genetic information.
The structure of a ‘typical’ cell is divided into 4 parts,w which are:
1 - cytoplasm
2 - organelles
3 - plasma membrane (cell wall)
4 - interstitial (watery) fluid - intracellular + extracellular
Where’s intercellular interstitial fluid found?
within the cell membrane/wall
Where’s extracellular interstitial fluid found?
exterior to the cell membrane/wall
What are the functions of the plasma membrane?
communication and regulation
How does the plasma membrane communicate?
receptors attach to chemical messengers which alters the cell activity
How does the plasma membrane regulate activity?
the membrane and membrane channels regulate what enters and exits the cells.
This maintaining ‘internal environment’ ensuring an ideal environment for cellular activity to take place
What does the Plasma membrane consist of?
- phospholipid membrane
- receptors
- glycoproteins, glycolipids and carbohydrates
- protein channels
What does phospholipid mean?
bi-layer
Phospholipid membranes are made of two layers:
- hydrophilic
- hydrophobic
Explain the HYDROPHILIC layer of a phospholipid membrane
- water loving
- leads in contact the the interstitial fluids, both intracellular and extracellular
Explains the HYDROPHOBIC layer of phospholipid membrane
- water hating
- tails within bi-layer, not in contact with fluids
What do the glycoproteins, glycolipids and carbohydrates do within the plasma membrane?
Enable communication with other cells
What do protein channels do within the plasma membrane?
enable movement of substances across the membrane
What do receptors do? and how?
They signal molecules. Activity can change by chemical messengers which attach to receptors on the membrane.
Give an example of when receptors signal
hormone adrenaline and neurotransmitters speed up heart rate
What kind of things are recognised by receptors on nerve endings?
signals such as pressure and temperature
What do nerves do?
Nerves convey information to the brain so we’re aware of a situation
Define the plasma membrane
A thin wall that separates one cell from the other cells and the environment
Substances enter the plasma membrane via 2 processes:
diffusion and osmosis
Explain diffusion
- particles distribute evenly within a solution
- movement is from high concentration to low concentration
- movement of solutes continues until both solutions are equal in strength
Explain osmosis
- movement of water molecules
- from low to high concentrate until equilibrium is achieved
Percentage of intracellular (ICF) fluid in the body
66% of body fluid