Basic cells and tissues (lesson 2) Flashcards
What is a cell?
A cell is the basic unit of life
Basic cell functions are to:
- Obtain ____ and ______
- perform ______ _______
- Eliminate ______ _______ and ____ produce
- Synthesise _____ and cell ______
- control _____ of materials
- Adapt/respond to _______ change
- nutrients, oxygen
- chemical reactions
- carbon dioxide, waste
- proteins, components
- exchange
- environmental
Cells are ____ ____ of all living organisms
building blocks
Where do all cells come from?
The division of pre-existing cells
cells are the smallest units that perform vital ______ functions
physiological
Define Homeostasis
The maintenance of a stable, internal environment.
the nucleus and the cytoplasm are part of the cell ____
interior
what 2 things does the cytoplasm contain?
cytosol (gel like fluid in the cytoplasm) and cell organelles
______ fluid is part of the cell exterior.
Extracellular
The cell membrane/plasma membrane can also be known as the _______
plasmalemma
What is the plasma membrane made up of?
a phospholipid bilayer with proteins and carbohydrates
Are the phospholipid heads hydrophobic or hydrophilic?
Hydrophilic heads
Are the phospholipid tails hydrophobic or hydrophilic?
Hydrophobic tails
The Functions of the cell membrane are:
- _____ _______
- _________ __ _______ with the _______
- _______ between the ___ and its environment
- ____ ______
- physical isolation
- regulation of exchange, environment
- communication, cell
- structural support
Name the barrier that surrounds the nucleus that is interrupted by nuclear pores
nuclear envelope/membrane
The nucleus contains chromatin, define chromatin.
Chromatin is a network of fibres made from protein and DNA
What happens to chromatin when a cell divides?
Chromatin condenses into chromosomes
What structure is found in the centre of the nucleus?
the nucleolus
The nucleolus is a ______ structure composed of _____ and _____ associated with DNA.
coiled, RNA, proteins
What is the function of the nucleus?
It stores and transmits genetic information in the form of DNA to synthesise proteins.
What are membranous organelles surrounded by?
Lipid Membranes
Name 5 membranous organelles
Endoplasmic Reticulum, Golgi Apparatus, Lysosomes, Peroxisomes and Mitochondria
Organelles that are not enclosed by a membrane and always in contact with the cytosol are known as ______
non-membranous organelles
Name 6 non membranous organelles
cytoskeleton, microvilli, centrioles, cilia, ribosomes and proteosomes
Describe the structure of the endoplasmic reticulum.
It’s a network of membranous channels extending throughout the cytoplasm.
Name the 2 types of endoplasmic reticulum you can get.
rough er and smooth er
what is another name for the rough er?
granular er
what is another name for the smooth er?
granular er
The ____ ER has ribosomes attached.
Rough
what is the function of the rough ER?
Responsible for the packaging and transport of proteins secreted by cell or distributed to other cell organelles (discharged)
The smooth ER is responsible for ____ synthesis.
lipid
What is the other function of the smooth ER?
The storage and release of calcium for muscle contraction and other cell activities.
The Golgi apparatus is found near to the _____.
nucleus
Describe the structure of the Golgi apparatus.
Stacks of flattened membranes containing chambers.
what are these flattened membranes of the Golgi known as?
cisternae
The function of the Golgi apparatus is the _______, ______ and _____ of _______ product and ______ enzymes. Also for transport to the ____ _______.
storage, alteration and packaging
secretory
lysosomal
plasma membrane
Name the 3 types of vesicles.
secretory vesicles, membrane renewal vesicles and lysosomes
What process do secretory vesicles perform?
Exocytosis, contents released to cell exterior
What are lysosomes?
Lysosomes are vesicles containing digestive enzymes
What is the function of a lysosome?
The intracellular removal of damaged organelles or pathogens
What are peroxisomes?
Vesicles containing degradative enzymes.
The function of peroxisomes is the _______ of _____ and other organic compounds (breakdown complex molecules to form simple ones), ______ of _____ compounds generated in the process.
catabolism, fats, neutralisation, toxic
What organelle is known as the powerhouse of the cell?
Mitochondrion
what is the mitochondrion the site of?
aerobic respiration
mitochondria has a ______ membrane.
double
The folds of the inner membrane (of the mitochondria) are known as the _____.
cristae
Cristae increase the ______ _____ exposed to the fluid content of the matrix.
surface area
What does the matrix contain and why?
metabolic enzymes to catalyse the reactions that provide energy for cellular functions.
What type of energy is produced in the mitochondrion (95%)?
ATP
Where will you find fixed ribosomes?
on the rough ER
Free ribosomes are found scattered in the ______.
cytoplasm
Each ribosome consists of _______ and ____ molecules.
protein and RNA
What is the function of a ribosome?
Its responsible for the synthesis of proteins from amino acids using information carried by RNA molecules, from DNA in the nucleus.
The ribosome is the site of ______ synthesis.
Protein
Proteins synthesised on free ribosomes pass into the ________.
cytosol
Proteins synthesised on fixed ribosomes go to the ______ ________.
Golgi apparatus
The centrioles direct ______ of _____in _____ ___________.
movement, chromosomes, cell division
What do centrioles organise?
The cytoskeleton.
The cytoplasm surrounding centrioles is the ______.
centrosome.
cilia are anchored by a _____ ______.
basal body
cilia assist the _____ of materials across the cell surface.
movement
what is the function of protesomes?
To breakdown and recycle damaged or abnormal proteins.
The cytoskeleton proteins are organised in ____ ________ or ______ _______.
fine filaments, slender tubes
What does the cytoskeleton provide?
skeletal strength and flexibility
what is the function of microvilli?
To increase the surface area to facilitate absorption of extracellular materials.
what does sarco have to do with?
Muscle
Name the 3 types of muscle cells.
smooth muscle cells, cardiac muscle cells and skeletal muscle cells
smooth muscle cells are under _____ control.
involuntary
Where are smooth muscle cells found?
in the walls of internal organs eg. blood vessels, gastrointestinal tract
what shape are smooth muscle cells?
spindle shaped cells
What do smooth muscle cells lack?
They lack visible striations.
smooth muscle cells have a _____ _____ nucleus.
single, central
cardiac muscle cells are under ______ control.
involuntary
Where are cardiac muscle cells found?
in the heart
Cardiac muscle cells are _____ cells.
branching
how many nuclei do cardiac muscle cells have?
they have one single central nucleus
In cardiac muscle cells are the striations invisible or visible?
Visible striations
Skeletal muscle cells account for approx. ____ of our body weight.
40%
Skeletal muscle cells are under ______ control.
voluntary
What are skeletal muscle cells connected to and why?
They are connected to bones for articulation/movement.
what shape are skeletal muscle cells?
They are elongated cells
Give me information about the nucleus in skeletal muscle cells.
there are multiple peripheral nuclei.
Skeletal muscle cells _____ ______ striations.
have visible
Name the 4 components of muscle.
muscle tissue, connective tissues, nerves and blood vessels.
myo______ > myo_______> muscle _____/fibre> ______> ______
myofilaments>myofibril>muscle cell/fibre>fascicle>muscle
What are nerve cells also known as?
neurones
A typical neurone is made up of: 1. 2. 3. 4.
- Dendrites
- Cell Body
- Axon
- Axon terminals/ telodendria
what is the neuron cell body made up of?
nucleus and perikaryon
An axon may be _______ or ___-________
myelinated or non-myelinated
Define myelinated
having a myelin sheath
why is having a myelin sheath beneficial?
Its a mix of proteins and phospholipids that icrease the speed of impulse
where are neuroglia found?
in the central nervous system
Ependymal cells line _____ in the brain and the _____ canal in the _____ cord. They assist in producing, circulating and monitoring _______ ______.
ventricles, central, spinal
cerebrospinal fluid
Astrocytes maintain _____-_____ barrier, provide _____ support, regulate ___, nutrient and dissolved gas ______, absorb and recycle _______ and form ____ tissue after _____.
blood-brain, structural, ion, concentrations, neurotransmitters, scar, injury
________ myelinate CNS axons an provide structural framework.
Oligodendrocytes
what is the function of the microglia?
Remove cell debris, wastes and pathogens by phagocytosis
What is a synapse?
A junction between 2 nerve cells, consisting of a minute gap across which impulse pass by diffusion of a neurotransmitter.