Module 3 Flashcards
1
Q
cell membrane
A
- semi permeable (some things can pass through and some can’t)
The cell membrane is essential in defining and containing the cell, allowing a specialized environment to be created within the cell that is important for specialized functions such as enzyme reactions to release energy from organic molecules (fat, carbohydrates), hormone manufacture and release, muscle contraction, nerve signals.
The genetic material within the cell (DNA) is selectively activated to produce unique cell types (bone, muscle), this process of creating different cell types is called differentiation.
2
Q
phospholipid bilayer in cell membrane
A
was able to create cell membrane by aligning the hydrophobic (lipid loving) fatty acid tails, and exposing the hydrophilic (water loving) heads to the water environments inside and outside the cell.
3
Q
Protein elements in cell membrane
A
A lot of protein elements that cross the cell membrane (red and purple) that control the movement of specific ions or signals into the cell.
4
Q
common functions within every cell
A
- cell is basic living unit of all organisms
- selective activation determines what type of cell it becomes (bone cell, muscle cell, etc)
- Cells are able to function in a similar way, many speciallized components, called organelles, each contribute a unique function essential for cell survival.
5
Q
cytoskeleton
A
protein scaffolding creating internal framework of the cell, holds organelles in place and allows cell to change shape
6
Q
nucleus
A
- variable location within the cell
- contains genetic material of cell (DNA) and nucleoli; site of RNA synthesis and ribosomal subunit assembly
7
Q
ribosomes
A
- in cytoplasm
- site of protein synthesis
8
Q
rough endoplasmic reticulum (ER)
A
- in cytoplasm
- has many ribosomes attached; site of protein synthesis
9
Q
smooth endoplasmic reticulum (smooth er)
A
- in cytoplasm
- site of lipid synthesis; participates in detoxification
10
Q
Golgi apparatus
A
- in cytoplasm
- modifies protein structure and packages proteins in secretory vesicles
11
Q
secretory vesicle
A
- in cytoplasm
- contains materials produced in the cell; formed by the Golgi apparatus; secreted by exocytosis
12
Q
lysosomes
A
- in cytoplasm
- contains enzymes that digest material taken into the cell; formed by the Golgi apparatus
13
Q
peroxisome
A
- in cytoplasm
- breaks down fatty acids, amino acids, and hydrogen peroxide
14
Q
mitochondrion
A
- in cytoplasm
- site of aerobic respiration and the major site of ATP synthesis
15
Q
microtubule
A
- in cytoplasm
- supports cytoplasm; assists in cell division and forms components of cilia and flagella
16
Q
centrioles
A
- in cytoplasm
- facilitate the movement of chromosomes during cell division
17
Q
cillia
A
- on the cell surface with many on each cell
- move substances over surfaces of certain cells
18
Q
flagella
A
- on sperm cell surface with one per cell
- propel sperm cells
19
Q
microvilli
A
- extensions of cell surface with many on each cell
- increase surface area of certain cells
20
Q
functions of the cell - cell metabolism and energy utilisation
A
- metabolism - all the chemical reactions within a cell
- potential energy released during metabolic reactions is used for cellular work - making molecules, muscle contractions, transport
21
Q
functions of the cell - synthesis of molecules
A
- cells make proteins, nucleic acids, lipids
- the types of molecules are made by specific cells is based on their differentiated structure, the structure is guided by the selective gene expression of DNA
22
Q
functions of the cell - communication
A
- chemical (hormone) and electrical (ion movement) signals are essential for cellular, tissue organ and organism survival
23
Q
functions of the cell - reproduction and inheritance
A
- each cell contains a full copy of your unique genetic information
- when cells divide, this information is copied for the new cell
- specialised cells transmit this information when we reproduce
24
Q
passive membrane transport
A
does not require ATP
- diffusion
- osmosis
- facilitated diffusion
25
active membrane transport
requires ATP
- active transport
- secondary active transport
- endocytosis
- exocytosis
26
diffusion
- movement is driven by concentration gradient
- molecules move from area of high concentration to low concentration
27
osmosis
- special name for diffusion of water across a selectively permeable membrane
- water moves by osmosis from an area of high water concentration to an area of low water concentration
28
lyse meaning
to burst
29
hypotonic solution
when a red blood cell is placed in a hypotonic solution, water enters the cell by osmosis, causing the cell to swell or even lyse
30
isotonic solution
when a red blood cell is placed in an isotonic solution, water moves into and out of the cell at the same rate. No net water movement occurs, and the cell shape remains normal
31
hypertonic solution
when a red blood cell is placed in a hypertonic solution, water moves by osmosis out of the cell and into the solution, resulting in crenation
32
facilitated diffusion
- driven by concentration gradient
- does not require ATP
- requires carrier molecule
- glucose movement into most cells
33
active transport
- movement of Sodium (Na+) and Potassium (K+) against their concentration gradients are directly driven by the chemical energy from ATP
34
secondary active transport
- movement of glucose against its concentration gradient is linked to the movement of sodium (Na+) down its concentration gradient
- the sodium gradient is established by active transport and use of ATP. The movement of glucose into cells of small intestine
35
endocytosis
movement into cells by vesicles
36
exocytosis
movement out of cells by vesicles
37
DNA
- is found within the nucleus of human cells
- DNA is loosely coiled as chromatin during normal cell function - this allows access to the DNA for the formation of messenger RNA (mRNA) within the nucleus
- mRNA then travels out of the nucleus to direct the formation of protein molecules
- DNA is tightly packed into chromosomes during cell division
38
transcription
formation of messenger RNA (mRNA) from DNA
- chromatin (loose DNA) separates to allow access to one side of the DNA double helix (pairs of nucleotides)
- a copy of a gene or segment of DNA strand is made by pairing specific individual RNA nucleotides with the DNA in sequence
- as more RNA nucleotides are added, and enzymes catalyse a bond between the RNA nucleotides, forming a messenger RNA (mRNA) strand
- this encoded 'message' (mRNA) then moves out of the nucleus into the cytoplasm to direct the formation of protein molecules
39
Translation
an mRNA sequence guides the formation of a protein molecule
Ribosomes - protein-based organelle in the cytoplasm that guides the synthesis of protein molecules from the mRNA sequence
- the information in the mRNA sequence is carried in groups of 3 nucleotides (codons)
- the structure and function of a protein is determined by its amino acid sequence
- the alignment of amino acids with the mRNA sequence requires additional types of RNA molecules
tRNA (transfer RNA) - each tRNA has 3 nucleotides (anticodon) that can pair with the mRNA codon
- there are unique tRNA molecules for each mRNA codon. Each tRNA is associated with a different type of amino acid that matches its anticodon, and an mRNA codon
- a ribosome guides the association between the mRNA and tRNA molecule. An mRNA codon pairs with the appropriate tRNA anticodon
- a peptide bon forms between amino acids aligned by adjacent codons in ribosome
- the next amino acid is aligned to the sequence and bonded to the growing chain of amino acids until a stop message codon is read
40
translation short
amino acids are linked to form a polypeptide chain, this chain is modified to become a protein
41
cell cycle
most of time a cell is involved in normal metabolic function, during growth and development, or tissue repair, cell division is required
42
interphase
G1 phase - cell function and metabolism, coordination of cell growth, replication, differentiation and death (apoptosis)
S Phase - DNA replication
G2 Phase - preparation for cell division, repair DNA damage and replication errors
Cell division mitosis - M Phase: formation of daughter cells
43
differentiation
development if specialised structures and function within cells
- selective activation and inactivation of segments of DNA
- many cell types with specific structure are required to contribute all the unique functions essential for our survival
