Cells Flashcards
Define a prokaryote cell
No nucleus Far smaller than a Eukaryote No organelles Has a cell wall Rapid mitosis Types: bacteria, archea Unicellular
A prokaryote is a unicellular organism that lacks a nuclear membrane-enclosed nucleus.
Define a eukaryote cell
Nucleus
Bigger than prokaryote
Organelles present
Types: human, animal cells, plants, fungi
Only plays/fungi have cell walls
Human and animal cells do not have a cell wall
Unicellular or multi cellular
Eukaryotes are organisms whose cells have a nucleus enclosed within a nuclear envelope.
What are the characteristics of life
7
different mums react greatly questioning more rarely
- metabolism
- reproduction
- growth
- vital force/QI/life force
- movement
- differentiation
- responsiveness
Characteristics of death
- loss of heart beat
- loss of brain function
- no vital force
- absence of breathing
Define homeostasis
The condition of equilibrium/balance in the body’s internal environment which is maintained by the body’s own regulatory processes
Define homeostatic control and what it is made up of
- Disruptors: change in homeostatic parameter
- Detectors: receptors that detect the disruption
- Control center: evaluates input to generate output
- Effectors: structures that receive the output e.g. sweating, dilation of blood vessels
A feedback system is a group of receptors and effectors communicating with their control center. What is the difference between negative and positive feedback
Negative: the output reverses the input e.g. body temperature, bloody pressure
Positive: amplifies/strengthens change in one of the body’s controlled conditions e.g. childbirth, bloody clotting, milk production
Systems of the human body -12
Skeletal Digestive Lymphatic Cardiovascular Respiratory Urinary Nervous Immune Endocrine Muscular Integumentary Reproductive
Body cavities
Cranial: brain
Thoracic: lungs, heart
Abdominal: stomach, liver, intestines
Pelvic: reproductive organs
Define the moder cell theory
All known things are made up of cells.
All cells come from pre existing cells by ‘division’
Cells contain DNA
Define the cell theory and when was it proposed?
All known things are made up of vital force and cells.
All cells come from pre existing cells by ‘division’
Cells contain DNA
1839
Name 3 metals that can accumulate in the body causing cell damage
Aluminum, lead and mercury
What causes free radicles
UV exposer, alcohol, pollution, stress, poor diet
Essential Antioxidents are
Vitamin C and E
Beta carotene
Selenium
Without these, oxidative stress/damage will happen causing genetic mutation
Internally the cell consists of
Organelles - structures in the cell
Cytoplasm - cell content excluding the nucleus
Cytosol - basic watery fluid
Define a cell wall (different to a cell membrane.)
The cell wall is found it plant, fungal and bacterial cells. These walls provide strength rigidity and surround the cell membrane
Define a cell membrane
It is a flexible semi permeable membrane the separates the cells external and internal environment. This control the transfer of molecules in and out of the cell. Structurally it is a phospholipid bilayer embedded with transmembrane protiens
Transmembrane proteins perform the following
- transport of substances in and out of cells e.g hydrogen and glucose
- immunological identify - helps our immune cells recognize out own cells (stopping WBC from attacking out body cells.)
- receptors - recognition sites for hormones
2 types of cell junctions
Tight: found in stomach, intestines, bladder. Transmembrane proteins fuse cells together to reinforce junctions and seal off passageways, preventing leaking
Gap: small fluid filled tunnels between neighboring cells e.g. nerves
Name the organelles
Nucleus, mitochondria, endoplasmic reticulum (smooth, rought,) ribosomes, Golgi apparatus, lysosomes, cytoskeleton
What is the optimum PH level for our bodies
7.35-7.45
What is a normal range of blood glucose levels?
4-7
Over 7 = diabetes
What is he fluid between cells called?
Interstitial fluid
Extracellular fluid vs intracellular fluid?
Extra=outside
Intra=inside
Where is 70% of our immune system location?
The digestive system
Define cell memory
Cells have the ability to remember experiences which influence the vital force in our bodies.
How do antioxidants support the body?
They donate electrons to unstable free radicles to stabilize them and stop the chain reaction of multiple cells being damaged
Is cytoplasm found inside the nucleus?
No
What role does each organelle play?
N = brain/controls activity - holds genetic material M= powerplant/energy. Make ATP in a process called cellular respiration, run on glucose R= produces proteins ER= proteins folding and transporting molecules around. Smooth ER=detoxification, makes some types of lipids G= post box/sorts, organizes, sends stuff out of the cell L= recycling/breaks down contents of the cell C= keeps the cell
How many chromosomes does a Gamete have?
23
How many chromosomes does a human body cell have?
46
What is interphase
Prophase
Metaphase
Anaphase
Telophase
What are the two main steps involved in protein synthesis
Translation and transcription
Define translation and transcription?
Transcription
Translation: where the ribosomes make the protein
What is a monomer
A building block
What is a peptide bond
The link between two amino acids along a protein chain
Define DNA and what is it’s job
DNA is a molecule composed of two polynucleotide chains that coil around each other to form a double helix carrying genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses.
What is the monomer for nucleic acids? And what are these made up of?
Nucleotides.
Phosphate, sugar, base
What are the three different types of RNA
tRNA - transfer amino acids to codon
mRNA - take message to ribosome
rRNA - makes protein
What is a phosphate
Salt
What is a hormone
A hormone is a chemical that is made by specialist cells, usually within an endocrine gland, and it is released into the bloodstream to send a message to another part of the body. It is often referred to as a ‘chemical messenger’.
What does mitochondria do?
Produces ATP to give our bodies energy to move. Glucose and oxygen come together to help produce ATP
What are ribosomes?
a small particle consisting of RNA. They bind mRNA and trRNA to synthesize polypeptides and proteins
Define Endoplasmic Reticulum (rough and smooth)
ER is a collection of tubes that make, package, and transport proteins and fats. Rough endoplasmic reticulum has protein-making ribosomes on its surface, so it helps make and process proteins. Smooth endoplasmic reticulum helps make and process lipids and helps detoxify drugs and alcohol
Define the golgi apparatus
The GA functions as a factory in which proteins received from the ER are further processed and sorted for transport to their eventual destinations: lysosomes, the plasma membrane, or secretion.
Define lisosomes
Lysosomes work like the digestive system to break down, or digest, proteins, acids, carbohydrates, dead organelles, and other unwanted materials using enzymes. When lysosomes burst, the digestive enzymes released start digesting its own cells.
What are microtubules and centrioles? (proteins)
They maintain the shape of the cell and allow the movement of other cells across the membrane
What are vacuoles?
Vacuoles are membrane-bound sacs within the cytoplasm of a cell that function in several different ways. In mature plant cells, vacuoles tend to be very large and are extremely important in providing structural support, as well as serving functions such as storage, waste disposal, protection, and growth.
What are vesicles
A vesicle is a small structure within a cell, consisting of fluid enclosed by a lipid bilayer. Vesicles form naturally during the processes of secretion (exocytosis), uptake (phagocytosis) and transport of materials within the cytoplasm.
What are the 7 steps of protein synthesis?
DNA unzips in the nucleus.
mRNA nucleotides transcribe the complementary DNA message.
mRNA leaves nucleus and goes to ribosome.
mRNA attaches to ribosome and first codon is read.
tRNA brings in proper amino acid from cytoplasm.
a second tRNA brings in new amino acid.
Define photo synthesis
Protein synthesis is the process in which cells make proteins. It occurs in two stages: transcription and translation. Transcription is the transfer of genetic instructions in DNA to mRNA in the nucleus. Translation is where the ribosome reads the code and produces the correct chain of amino acids to for the protein
What is cytokenisis?
process of cell division, which divides the cytoplasm of a parental cell into two daughter cells
