Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Fundamentals - Y1 > Basic Biology > Flashcards

Basic Biology Flashcards

Enzymology, Cell Organelles, Membrane Structures and Components, Biomolecules, Nutrients and Vitamins, Meiosis, Cell Proliferation and Mitosis, Cell Specification.

1
Q

What is metabolism and what is the purpose of it?

A

Chemical reactions that occur in a living organism. The purpose is to produce energy, biosynthesis and excretion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define anabolism.

A

Synthesis of larger molecules from smaller ones (requires energy).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define catabolism.

A

Synthesis of smaller molecules from larger ones (releases energy).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 5 types of electron carriers?

A 
Flavoproteins (NADH/NAD+)
Cytochromes (haeme in haemoglobin)
Copper atoms in mitochondrial membrane
Uniquinane/Co-enzyme Q
Iron-sulfur proteins (Fe3+/Fe2+)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Purpose of ATP.

A

Used as an energy intermediate. Produces 7.3kJ of free energy when hydrolysed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Purpose of Enzymes.

A

Biological catalysts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

6 Types of Enzymes.

A 
Transferase
Ligase
Oxidoreductase
Isomerase
Hydrolase 
Lysases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Characteristics of Enzymes.

A
  • Globular Proteins
  • Control metabolic reactions rate
  • Lower activation energy
  • Not consumed (re-usable)
  • Substrate specific
  • Shape of active site determines substrate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define substrate.

A

The reactant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define active site

A

Region where substrate binds + undergoes chemical reactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define co-factor.

A

Inorganic ions (Ca2+) which may be charged during the reaction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define co-enzyme.

A

Organic non-protein molecule (NAD+) that are a subset of co-factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define prosthetic group.

A

A co-factor permanently attached to an enzyme.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Define apoenzyme.

A

Enzyme with a co-factor removed (inactive catalytically).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Define haloenzyme.

A

Enzyme with co-factor attached.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the Lock-and-Key model.

A
  • Active site is rigid shape
  • Substrate needs to be matching shape
  • No change in the active site shape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the Induced fit model.

A
  • Active site is flexible
  • Shape of enzyme, active site + substrate adjust (improves catalytically)
  • Greater range of substrate specificity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does temperature effect enzyme activity.

A

Increases until reach optimum temperature where the enzyme begins to denature causing a decrease in activity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does pH effect enzyme activity.

A

Enzymes need to be around optimum pH decreases otherwise -> Specific to each enzyme.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does substrate concentration impact enzyme activity.

A

Maximum activity occurs when all enzymes are saturated so it will reach maximum reaction velocity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How do competitive inhibitors effect enzyme activity.

A

They are a similar shape to substrate so they bind to the active site meaning substrate can no longer bind.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do non-competitive inhibitors effect enzyme activity.

A

Different shape to substrate but bind to enzyme in a allosteric place which alters shape of the active site meaning substrate no longer complimentary.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe allosteric modulators.

A

Can be inhibitors or activators but are different shaped to the substrate and are involved in feedback inhibition (switches process off when not needed).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Importance of enzymes.

A

Can be:

  • Diagnostic markers of diseases
  • Biochemical estimations + detections
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Characteristics of Prokaryotic Cells.

A

-> Bacteria and Archaea
- Single-celled with DNA being circular
- Lack organelles
- DNA in nucleiod, no separation
- Rigid cell walls
- Functional structures in cytoplasm
Have Pili or Fimbriae and some have flagella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Characteristics of Eukaryotic Cells.

A
  • > Animals and Plants
  • Single of multicellular
  • Contain organelles - which are specialised for their function
  • DNA organised into chromosomes in the nucleus
  • Nucleus surrounded by cytoplasm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Types of Cytosol organelles.

A

Mitochondria, Endoplasmic Reticulum (ER), Golgi apparatus, Lysosomes, Peroxisomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Types of Inclusions.

A

Lipid droplets, Glycogen granules, Ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Types of Protein Fibres.

A

Cytoskeleton, Centrioles, Cilia, Flagella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Describe Sub-Cellular Fractionation.

A
  • Disruption of plasma membrane
  • Ultracentrifugation
  • Cell compartments separate based on size and density
  • Further density-gradient centrifugation can separate individual components from each fraction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Describe Cell Membrane.

A 
Phospholipid bilayer
Physical isolation
Regulation of exchange
Communication
Structural support
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Describe Cytoplasm.

A

Semi-fluid material surrounding organelles
Site of many cellular activities
Offers cell support
Medium for internal cellular transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Describe Nucleus.

A

Cells control centre
Regulates all cellular activity
Contains DNA (hereditary information)
Consists of nucleoplasm bounded by nuclear envelope (Two membranes - Inner/Outer/Pores)

Nucleolus - Transcribes and assembles rRNA
Chromatin - DNA looped around histone proteins
Nuclear pores - Allows communication between nucleus and cytosol, Ions + small molecules pass freely, Allows cell to restrict DNA to nucles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Describe Endoplasmic Reticulum (ER).

A

A system of folded, interconnected membrane vesicles.

  • Large flattened sac-like structures (cisternae)
  • Internal space = Lumen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Describe Smooth ER.

A

No ribosomes

Biosynthetic + Biotransformational activities (Lipids/Steroids/Steroidal hormones) - in liver/kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Describe Rough ER.

A

Ribosomes on cytosolic side

Site of protein synthesis -> Protein transported to lumen for modification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Describe Golgi Apparatus.

A

Large sac-like membrane vesicles, associated vesicles + tubules
Processing station
- Package + distribute cell products (for internal/external use)
- Vesicles budding off ER travel and are accepted by Golgi
- Vesicles budding off Golgi travel to other organelles/cell surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Describe Vesicles.

A

Similar membrane to plasma membrane

Internal conditions different to cytosolic environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Describe Vacuoles.

A

Component for storage + transport (often temporarily)

Largest in plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Describe Lysosomes.

A

Membrane bound vesicles used in intra/extracellular digestion of biomolecules + old cells.
Characteristics: 0.5-1um, Contain lysozymes, Lumen has low pH, Acid hydrolases (active at low pHs).
Special carbohydrate to prevent self-destruction
Larger amount in white blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Describe Peroxisomes.

A

Membrane bound from ER
Characteristics: 0.1-1um, Contain oxidase + catalase, Detoxify + decompose harmful substances
Lots in the liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Describe Vesicles Transport.

A

Move molecules in a cell

Recognise + fuse with target membranes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Describe Secretary Vesicles.

A

Contains materials to be excreted from the cell
- Removal of waste
- Release chemical signs (hormones)
Vesicle fusion (Full/Kiss-and-run - reusable)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Describe Mitochondria.

A

Site of aerobic respiration + energy production
Double membrane:
- Inner = Folded forming cristae
- Area within cristae = matrix
- Gap = Inter-membrane space
Membrane in inter-membrane space allow for cell death (apoptosis)
Distribution in cells + tissue depend on function (muscles = high)
Matrix - Contains enzymes, ribosomes, granules, DNA, machinery to form ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Describe Cytoskeleton.

A 
3D structure that fills the cytoplasm
Roles:
- Cell Movement
- Cytokinesis (cell division)
- Organisation of organelles

Composed of:

  • Microfilaments = 3-6nm, threadlike, mainly actin, carry out movement
  • Microtubules = 20-25nm, cylindrical tubes, a + B tublin subunits, determine cell shape, used for flagella + cilia movement
  • Intermediate filaments = 10nm, overlapping + twisted conformation, provide tensile strength, anchor organelle + nucleus, form junctions between cells + matrix
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Describe the Structure of the Cell Membrane Lipids.

A

Most membrane lipids are amphipathic
Many are phospholipids (glycerophospholipids/sphingolipids)
Sterols have stabilising roles
Proteins are associated to surface/span membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Describe Glycerophospholipids.

A

Glycerol as polar head
Attached to a phosphate ion and an R-group
Helps to fine tune membrane properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Describe the two types of Sphingolipids.

A 
Sphingomyelin = Phosphocoline head group
Glycosphingolipids = Mono/oligo-saccharide head group
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Explain the Main Constituents of a Cell Membrane.

A 
Phospholipids = Membrane formation
Glycolipids = Antigen recognition 
Sterols = Membrane fluidity
Proteins = Signalling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

State the 7 types of Amphipathic Phospholipids.

A 
Phosphatidylcholine (PC)
Phosphatidylethanolamine (PE)
Phosphatidylglycerol (PG)
Phosphatidylinositol (PI)
Phosphatidylserine (PS)
Diphosphatidylglycerol (DPG)
Sphingomyelin (SP) - Animals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

State the 2 types of Gylcolipids.

A

Cerebrosides (mono)

Gangliosides (oligo - inc sialic acid -ve charged)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

State the type of Sterol in Humans and its Properties.

A

Cholesterol

Properties

  • Amphipathic
  • Intercalates into bilayer
  • Influences membrane fluidity + decrease ion permeability + small polar molecules
53
Q

Describe the Phospholipid Bilayer.

A

Hydrophobic core stabilised by Van Der Waals forces
Hydrophilic head groups interact by ionic interaction
Movement between layers stabilised by flippases
Only functions in fluid state
Lateral diffusion is fast/Transverse is slow
At low temperatures it solidifies = gel phase

54
Q

Explain the Factors that Affecting Membrane Fluidity.

A

Longer fatty acid chains - Reduce Fluidity
-> Increased Van Der Waals forces
Unsaturated fatty acid chains - Increased Fluidity
-> Chains no longer linear - Decreased forces - Desaturate enzymes re-tailor chain
Sterols in fluid - Decrease Fluidity
-> Restrict movement of compounds
Sterols in gel phase - Increase Fluidity
-> Facilitate movement of other membrane compounds

55
Q

State the 3 Membrane Proteins.

A

Integral
Lipid-Anchored
Peripheral

56
Q

Explain the Integral Membrane Proteins.

A 
Amphipathic
Span the membrane (integral polytopic)
Partially embedded (integral monotopic)
57
Q

Explain the Peripheral Membrane Proteins.

A

Lack hydrophobic regions
Do not interact with fatty acid ends of membrane lipids
Associated with membrane structure
- Electrostatic attraction
- Hydrogen bonding (to protein or polar head groups)

58
Q

Explain the Lipid-Anchored Membrane Proteins.

A

Found in both membrane surfaces
- Protein located on membrane surface
Anchored via covalent bonds to lipid molecules within membrane
- Fatty-acid anchored membrane proteins
- Synthesised + attached to a lipid in membrane
Isoprenylated membrane proteins
- Synthesised + modified by addition of multiples of the isoprenylgroup

59
Q

State the Functions of Membrane Proteins.

A 
Transport
ATP Production
Biotransformations (metabolism)
Receptors
Cell-cell recognition
60
Q

Explain Lipid Rafts.

A

Phospholipids + proteins distributed asymmetrically in membrane
- Highly organised membrane structures
- Thicker
- Rich in cholesterol and sphingomyelin
Accumulate molecules (ie transmembrane proteins, lipid-anchored proteins + glycoproteins)

61
Q

State the Roles of the Cell Membrane.

A 
Physical isolation
Regulate exchange with environment
Communication between cell + environment
Structural support
Cellular identification
62
Q

Explain the 4 Transport Mechanisms.

A

Simple diffusion

  • High -> Low conc. gradient
  • Small + hydrophobic molecules (O2,CO2)

Osmosis
- Water diffusion High -> Low water potential

Facilitated Diffusion

  • High -> Low conc. gradient
  • Require transport protein
  • Ions (K+,Na+), Monosaccharides, Amino Acids

Active Transport

  • Low -> High conc. gradient
  • Ions, Glucose, Amino Acids
  • Requires energy (ATP, Electrochemical gradient)
63
Q

State the Process that occur over a Mobile Membrane.

A 
Endocytosis
Exocytosis
Pinocytosis
Phagocytosis
Receptor-Mediated Endocytosis
Exocytosis
64
Q

State the formula for Carbohydrates.

A

(CH2O)n

65
Q

Describe the Functions of Carbohydrates.

A

Primary - Short-term immediate energy generation
Secondary - Immediate-term energy storage (glycogen)
Tertiary - Structural components (cellulose)

66
Q

State the bond between Monosaccharides.

A

Glycosidic

67
Q

State the Products Formed by Condensation Bonds between Monosaccharides.

A

Disaccharides (sucrose)
Oligosaccharides (ABO glycolipids)
Polysaccharides (cellulose)

68
Q

Describe the difference between Alpha and Beta Glucose.

A 
Alpha = OH bonds on same side on carbon 1 + 6
Beta = OH bonds on opposite sides on carbon 1 + 6
69
Q

State the main Functions of Lipids.

A

Energy Storage
Heat/Insulation
Structural components of cell membranes
Communication

70
Q

Describe the Characteristics of Lipids.

A

Non-Polar
Not very soluble in water, Soluble in non-polar/weakly polar organic solvents
Saturated = Single C-C bonds, linear appearance, solid at RTP
Unsaturated = 1+ C=C bond, C=C gives distinct bend, reduces melting point liquid at RTP
Carboxyl Head - Non-polar + Hydrophilic
Fatty Acid Chain - Hydrophobic

71
Q

Describe Triglycerides.

A

Glycerol + 3 Fatty Acid Chains
Stored as cytoplasmic ‘lipid droplets’
Main storage for energy: Long term + high in energy

72
Q

Describe Phospholipids.

A

Glycerol + 2 Fatty Acid Chains + Phosphorylated Alcohol

73
Q

Describe Eicosenoids.

A

Consists of: Prostaglandins (PG’s), Thromaxones (TX’s), Prostacyclins (PGI’s), Leukstrienes (LT’s)
Derived from arachidonic acid

74
Q

Describe Isoprenoids - Steroids.

A

Built around 4-ringed hydrocarbon skeleton
Cholesterol is the base of all steroid hormones
- Glucocorticoids
- Mineralocorticoids
- Androgens
- Oestrogens
- Progesterones

75
Q

Describe Isoprenoids - Sterols.

A

Cholesterol

  • Mammalian cell membranes
  • Precursor of steroid hormones + bile salts

Ergosterol
- Cell membrane component in fungi

Phytosterol
- Plant sterol (suggested cholesterol-lowering effect)

76
Q

State the Roles of Proteins.

A 
Enzymes
Structural
Motility
Regulatory
Transport
Hormone
Receptor
Defensive
Storage
77
Q

State the Structure of Amino Acids.

A

NH2CHRCOOH

78
Q

State the 4 Groups of Amino Acids.

A

Group I - Non-Polar
Group II - Polar
Group III - Acidic
Group IV - Basic

79
Q

State the Name of the Bond between Amino Acids.

A

Peptide bonds formed from condensation reactions.

Forms an N-C-C backbone

80
Q

Describe the 4 Polypeptide Structures.

A

Primary: Amino acid sequence
Secondary: H-bonds between polypeptide backbone at regular intervals forms a-helix (coils) and b-sheets (folds)
Tertiary: Interaction between R-groups + backbone from ionic, disulphide bridges and H-bonds
Quaternary: Interaction between 2+ polypeptide chains (Haemoglobin has 4)

81
Q

Explain the Function of Nucleotides.

A

Allow living organisms to pass information to future generations and carries metabolic energy.

82
Q

State the 2 types of Nucleotides.

A

Purines - Adenine + Guanine

Pyramidines - Thymine, Cytosine + Uracil

83
Q

Describe Deoxyribose nucleoties (DNA).

A

Four nucleotides: A + T, C + G

Sugar = D-deoxyribose

84
Q

Describe Ribose nucleotides (RNA).

A

Four nucleotides: A + U, C + G

Sugar = D-ribose

85
Q

Explain the DNA Double Helix.

A

Base pairing between two complementary strands (5’ to 3’ vs 3’ to 5’ strands) which forms right handed helix with a sugar phosphate backbone.

86
Q

Describe Meiosis in simple terms.

A

Gametes (haploid cells) fuse which allows organisms to reproduce, creating genetically different offspring to their parents.

87
Q

Describe the 2 types of Reproduction.

A

Sexual

  • Combination of haploid sex cells (gametes)
  • Fertilisation forms zygote
  • Change in genetic information so genetic differences
  • Restores diploid number from gamete fusion

Asexual

  • Via Mitosis ONLY
  • Genetically identical offspring
88
Q

State all the Stages Involved in Meiosis.

A 
DNA Replication
Meiosis I
Prophase I
Metaphase I
Anaphase I
Telophase I
Meiosis II
Prophase II
Metaphase II
Anaphase II
Telophase II
89
Q

Describe Meiosis I.

A

Duplicated maternal + paternal homologous chromosomes pair up alongside each other
-> Genetic recombination
Line up at equator of meiotic spindle
Homologous are pulled apart and separated into 2 daughter cells.

90
Q

Describe Prophase I - Meiosis.

A

Chromosomes duplicated
Chromosomes condense + become visible
Synapsis + crossing over occurs
-> Increases genetic variation

91
Q

Describe Metaphase I - Meiosis.

A

Homologous chromosomes align at the metaphase plate

Centromeres of homologous chromosomes are oriented towards opposite poles.

92
Q

Describe Anaphase I - Meiosis.

A

Mircotubules attaches to the kinetochores shorten
Homologous chromosomes move to opposite cell poles
Centromeres don’t break (chromatids don’t separate).

93
Q

Describe Telophase I - Meiosis.

A

Spindle fibres disintegrate and cytokinesis occurs

Each daughter cell has half the number of chromosomes.

94
Q

Explain the Importance of Genetic Variations.

A

Generates haploid cells genetically different from each other
Produces individuals with novel genetic combinations
- Can survive + reproduce in variable environments
- Removes harmful mutations from a population.

95
Q

Explain Proliferation.

A 
The physical process of cell division
Main Type in Eukaryotes = Mitosis
Increases somatic cell number
Occurs in most tissues
Critical in maintaining homeostasis
Begins in embryogenesis continues throughout lifespan
96
Q

Describe the different Proliferate Abilities.

A

Unable to:
Cardiac myocytes, Neurones

Can resume proliferation from G0:
Skin fibroblasts, Smooth muscles cells, Epithelial cells of internal organs

Continual proliferation:
Blood cells, Skin epithelial cells

97
Q

Describe the Regulation of Cell Proliferation.

A

Environment - Nutrients, Temperature, pH, O2
Positive/Negative - Cell adhesion, Growth factors
Intracellular - p53, Cytochrome C, Bcl proteins

98
Q

Describe Mitosis in simple terms.

A

The copy of an existing cell to produce genetically identical cells usually for growth and repair.

99
Q

Describe the Stages involved in Mitosis.

A

S-Phase: DNA Synthesis
M-Phase: Nuclear division (mitosis) + Cytokinesis
G1 Phase: Gap phase 1
S-Phase: Period of cell growth + proteins and organelles doubled
G2 Phase: Gap phase 2
M-Phase: Cell divides into two

100
Q

Explain the Importance of Gap Phases in Mitosis.

A

To grow and monitor internal + external conditions.

101
Q

Describe G1 Phase - Mitosis.

A

Takes approx. 9.5 hours
Ensures:
Cell large enough to enter S-Phase

102
Q

Describe G2 Phase - Mitosis.

A 
Takes approx. 2.5 hours
Ensures:
Cell completely replicated
Replication errors corrected
Cell large enough to divide
103
Q

Explain how Mitosis is Regulated.

A

Information from: Cell cycle events (nutrients, cell-density, growth factors)
External environment: Cyclins, Cyclin-dependent kinases (CDK)
Regulatory proteins bind to CDKs causing phosphorylation and activation

104
Q

Describe S Phase - Mitosis.

A

Chromosomes replicate
New DNA synthesised -> Duplicate chromosome constructed
Chromosome visible during division
After replication:
Each chromosome forms 2 identical chromatids
Chromatids joined at the centromere

105
Q

State the Stages of M-Phase - Mitosis.

A 
Prophase
Prometaphase
Metaphase
Anaphase
Telophase + Cytokinesis
106
Q

Describe Prophase - Mitosis.

A

Chromosomes condense
- Nuclear membrane and nucleoli disappear
Outside nucleus
- Mitotic spindle begins to form (centromeres, aster + microtubules)
- Centromeres move away from each other

107
Q

Describe Prometaphase - Mitosis.

A

Nuclear envelope forms

Microtubules attach to the chromatids at the kinetochores

108
Q

Describe Metaphase - Mitosis.

A

Centromeres are at opposite poles
Chromosomes line up at the metaphase pole
All chromosomes are attached to each of the pole

109
Q

Describe Anaphase - Mitosis.

A

Connection between chromatids at the centromeres is cleaved
- Each chromatid is now a daughter chromosome
Chromosomes are pulled to opposite poles as cell elongates

110
Q

Describe Telophase + Cytokinesis - Mitosis.

A 
Two daughter cell nuclei form
- Nuclear envelope forms, cytoplasm divides
Chromosomes become less dense
Contractile ring assembles
- Actin + Myosin filaments
- Cytoplasms divided in 2
111
Q

State the Importance of Mitosis.

A

Regulates development

  • Maintains size, morphology + organ function
  • Involved in ageing, oncogenesis + regenerative medicine
112
Q

Describe the effect of Abnormal Proliferation.

A

Uncontrolled cell division/death which is the cause of most metastasis -> cancer

113
Q

Describe Cell Specialisation/Differentiation.

A

Cell changes from one type to another
Usually results in a more specialised cell type
Determines role of the cell

114
Q

State the main types of Stem Cells.

A

Embryonic stem cells
Adult stem cells
Induced pluripotent stem cells

115
Q

Describe Embryonic Stem Cells (Blastocysts).

A

Isolated from the inner cell mass of blastocysts
Can differentiate into all specialised cell types
Division results in ‘self-renewal’
Totipotent and Pluripotent

116
Q

Describe Adult Stem Cells (Bone Marrow).

A

Found in various tissues
- Obtained after birth
- Large number in umbilical cord blood + bone marrow
Act as repair systems
Progenitor cells
- Make cells to renew cells (maintains cells)
- Divided into 2 different cells (precursor + progenitor)

117
Q

Describe Induced Pluripotent Stem Cells (iPSC).

A

Lab generated - Reprogrammed differentiated adult cells
Used for research
Self-renewing (like embryonic stem cells)

118
Q

State and Describe the Potents of Stem Cells.

A

Totipotent - Any cell type
Pluripotent - Any cell type, except placenta
Multipotent - Limited cell differentiation types
Oligopotent - Few cell differentiation types
Unipotent - One cell differentiation type
Progenitor cell - Decedents of stem cells that can further differentiate

119
Q

Describe Blood Cells.

A

Formed in bone marrow from multipoint haematopeoietic stem cells
Erythrocytes (Red blood cells)
Leukocytes (White blood cells)
Platelets

120
Q

Describe Neurones (Cells).

A

Self-renewing multipoint stem cells
-> Located in subventricular zone + hippocampus
Purpose: Transmit information, oldest + longest cells, lack centrioles
Astrocytes
Oligoadendrocytes

121
Q

Describe Sperm Cells.

A 
Purpose: Form organelles
Spermatogenesis
- Haploid spermatozoa develop from germ cells in seminiferous tubules
- Totipotent stem cells
Specialisations:
- Head (acrosome - enzyme + nucleus)
- Tail (undulipodium - movement)
- Small + thin
122
Q

Describe Tissues.

A

Organised communities of cells
Work together to carry out specific tissues
Role determined by cell types
Categories: Connective, Epithelial, Muscle, Nervous

123
Q

Describe Epithelial Tissues.

A 
Found: 
- Outer layer of skin
- Lining of body cavities
- Blood + lymph vessels
Protects exposed + internal surfaces from abrasion, dehydration + destruction
124
Q

Describe Connective Tissues.

A

Cells + extracellular matrix (ECM)
Function: Protection, Support + Integration
Connective tissue proper, Loose + Dense irregular
Dense regular, Adipose tissue, Cartilage, Blood, Bone + Haemapoietic tissue

125
Q

Describe Muscle Tissues.

A

Contract + Produce movement
Skeletal (voluntary) muscle
Smooth muscle (involuntary)
Cardiac muscle -> heart (involuntary)

126
Q

Describe Nervous Tissues.

A

Specialised for propagation of electrical signals
98% of tissue in brain + spinal cord
Functions: Sensory input, Integration, Control of muscles, Glands, Homeostasis + Mental activity

127
Q

Describe an Organ.

A

Collection of tissues joined in a structural unit for a common function
Made of many tissue + several cell types
Example: Heart

128
Q

Describe an Organ System.

A

Group of organs that work together as a biological system to perform one or more function.

Fundamentals - Y1 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions