some deffinations to remember
Carrier: An individual that has one copy of a recessive allele that causes a genetic disease in individuals that are homozygous for this allele
Homozygous: Having two identical alleles of a gene
Heterozygous: Having two different alleles of a gene
Locus: The particular position on homologous chromosomes of a gene
Genotype: The allele combination of an organism
Codominant Alleles: Pairs of alleles that both affect the phenotype when present in a heterozygote
Recessive Allele: An allele that only has an effect on the phenotype when present in the homozygous state
Dominant Allele: An allele that has the same effect on the phenotype whether it is present in the homozygous or heterozygous state
Phenotype: The characteristics of an organism (determined by a combination of genotype and environmental factors)
basic teechniques to know for exam
2. DNA fingerprinting
3. DNA profiling
1. multiplying DNA (PCR)
Stem cells = cells, that have
ability to differentiate
and divide
Cells capacity to divide and differentiate decreases during development
A. Totipotent: can become any type (cells from early embryos – 1-3 days)
B. Pluripotent: – cells can form any cell type except embryonic
membrane, placenta – from blastocyst inner cell mass (5 to 14 days)
C. Multipotent: – cells are to certain extent differentiated, but can still
become a number of different cell types – found in fetal tissue, cord
blood, adults in varying locations
D. Unipotent: can only become one cell type.
E. Nullipotent: cannot divide (red blood cells)
How/for what could one use stem cells?
A. Adult stem cells are transplanted for therapy
e.g. Bone marrow and variety of blood disorders (leukemia, lymphoma..)
B. Embryonic stem cells are transplanted in therapy
= culturing and differentiating embryonic stem cells to replace lost/damaged tissues, even grow new organs. treatments for
– Cardiac – following heart damage
– Nervous system – stroke/spinal cord, Parkinson’s, Alzheimer’s
– Burns
– Diabetes
– Solid organ regeneration
Stargardt’s disease:
The progressive vision loss associated with Stargardt disease is caused by the death of photoreceptor cells in the central portion of the retina called the macula.
cell cycle
meiosis
Mitosis: it is a process of nuclear division by which replicated copies of cells DNA are organized into chromosomes. the identical copies of the DNA are then divided equally between two daughter cells.
Mitosis is four steps process
1. prophase
2. metaphase
3. anaphase
4. telophase
C. ANAPHASE:
chromosomes is broken down into chromatids and taken to opposite directions.
D. TELOPHASE
1. the nuclear membrane begins to reform and chromosomes relax as DNA unwinds.
telophase is followed by cytokinesis(division of cytoplasm).
cytoplasm is divided into two equal parts means original cell is divided into two daughter cells.
B. METAPHASE:
1. CHROMOSOMES MOVE TO CENTER OF CELL BY SPINDLE MICROTUBULUSES
A. PROPHASE:
1. nuclear membrane and nucleolus
begin's to fade.
2. dna condences to form chromosomes.
3. mitotic spindle begins to form and attach
to center of chromosomes
extra knowledge
Tumors:
Tumors are abnormal cell growths resulting from uncontrolled cell division and can occur in any tissue or organ.Diseases caused by the growth of tumors are collectively known as cancers.
Oncogenes:
An oncogene is a gene that has the potential to cause cancer
A mutagen is an agent that changes the genetic material of an organism.
plasma membrane
Types of Transport
Tonicity is a term that describes
the ability of a solution to cause a
cell to gain or lose water
BULK TRANSPORT:
The spontaneous breaking and reforming of the bilayer, allowing larger materials to enter or leave the cell without having to cross the membrane (this is an active process and requires ATP hydrolysis)
Subtopic
Vesicular Transport:
Materials destined for secretion are transported around the cell in membranous containers called vesicles
materials pass through two places and are then secreted:
1.Endoplasmic Reticulum
2.Golgi Apparatus
Endoplasmic Reticulum:
Materials are transported from the ER when the membrane bulges and then buds to create a vesicle surrounding the material
Golgi Apparatus:
The vesicle is then transported to the Golgi apparatus and fuses to the internal (cis) face of the complex
Passive Transport
1. movement of material from high concentration to low concentration)
2. It does not require ATP
There are three main types of passive transport:
1. Simple diffusion – movement of small molecules (e.g. O2, CO2, etc.) through plasma membrane.
2. Osmosis – movement of water molecules.
3. Facilitated diffusion – movement of large or charged molecules via membrane proteins (e.g. ions, sucrose, etc.)
Osmosis is the net movement of water molecules across a semi-permeable membrane from a region of low solute concentration to a region of high solute concentration (until equilibrium is reached).
Effects of Solute Concentrations on Cells
Aliaihe
Active Transport
1. movement of materials from low concentration to high concentration).
2. it requires ATP.
Sodium-Potassium Pump
PROKARYOTIC AND EUKARYOTIC CELL STRUCTURE AND FUNCTIONS
PROKARYOTIC CELL STRUCTURE AND FUNCTIONS
EUKARYOTIC CELL STRUCTURE AND FUNCTIONS
pond organisms
Paramecium is a unicellular organism that lives in freshwater. It feeds by ingesting small items of food through its oral groove. Food is digested inside the animal’s body, inside a food vacuole. Paramecium is one of a group of organisms known as ciliates because they move in water using rows of tiny cilia, which beat to propel them along.
Excretion: Waste products are excreted through anal pore.
Metabolism: Cytoplasm contains enzymes that break down substances to release energy
Nutrition: Paramecium consumes smaller organisms that are packaged into food vacuoles. “Food” is gradually digested and absorbed into the cytoplasm.
Growth and Development: The cell will enlarge until a maximum size, at which point it will divide
Reproduction: Nucleus of cell divides via mitosis to make extra nuclei needed for cell to reproduce
Homeostasis:
contractile vacuoles fill up with water and expel it to regulate cell’s water content
Responds to Environment: Paramecium control beating of cilia to move in different directions in response to changes in environment
Chlamydomonas is green algae. Chlamydomonas is a common component of plankton and are often used by biologists to study pollution and photosynthesis.
Excretion: Oxygen, a by-product of photosynthesis, freely diffuses out through the cell membrane
Metabolism: Cytoplasm contains enzymes that break down substances to release energy
Nutrition: Chlamydomonas absorb CO2 into the chloroplasts found in its cytoplasm. “Food” is synthesized via photosynthesis.
Growth and Development: Photosynthesis happens inside the cytoplasm (carbon dioxide is converted to compounds needed for growth)
Reproduction: Nucleus of cell divides via mitosis to make extra nuclei needed for cell to reproduce (usually asexual)
Homeostasis: contractile vacuoles fill up with water and expel it to regulate cell’s water content
Responds to Environment: A light-sensitive “eye spot” allows Chlamydomonas to sense light and swim to it using its flagella. eyespot area name is PYRENOID.
DIFFERENT
made up of cells: single-celled organisms with nuclei and many other organelles.
Characteristics of life
8. EXCRETION
4. REPRODUCTION
3. HEMOSTASIS
7. METABOLISM
2. RESPOND TO ENVIRONMENT
1. MADE UP OF CELLS
6. NUTRITION
5. GROWTH AND DEVELOPMENT
CELL
CELL THEORY
cell theory has 3 basic principles,
1. all organisms are composed of cells.
2. all cells come from pre-existing cells.
3. cells are smallest unit of life.
all living organisms are made up of cells
Robert hook
key terms of term # 3
+10p if the terms and concepts are clearly organized in a meaningful way. No long explanations are needed.
Assessment criteria: 10 p. If main terms, concepts (structures, processes, theories) are there.
A3: 20p. handwritten mindmap, covering the term contents, showing links between key terms/processes/structures.
