Mod 5 Flashcards
Stamen
Name for all the male parts of a flower
Carpel
Name for all the female parts of a flower
Anther
Part of stamen where pollen grains (plant sperm) are formed
Filament
Stalk that carries the anther
Stigma
Part of the carpel, the sticky top in the centre of the flower to which pollen adheres
Style
Joins the stigma to the ovary
Ovary
Where ovules are formed and where fertilisation occurs
Binary Fission
Chromosomes are copied and cell is split into two, growing new membrane and wall (bacteria and some protea)
Budding
A bud grows as an outgrowth and the nucleus produces a smaller daughter nucleus which migrates to the bud (e.g hydra, coral and some protists)
Spore Formation
Spores are produced inside a sporangium and released when the sporangium wall disintegrates. They then germinate and form a new fungus (e.g moss, fungi and ferns)
Hormones
Chemical substances produced in the body that controls and regulates the activity of certain cells or organs
FSH
Follicle stimulating hormone triggers the release of oestrogen
Oestrogen
Triggers the release of Luteinising Hormone
LH
Triggers ovulation and formation of corpus luteum
Corpus Luteum
Secretes progesterone
Progesteroen
Maintains uterine lining
Oxytocin
Triggers contractions
Prolactin
Stimulates milk production
Selective breeding
Example of agricultural manipulation where animals with favourable characteristics are bred together (e.g wheat varieties with faster growth rates, drought, disease resistance, larger seed kernels)
Artificial Pollination
Agricultural manipulation which involves transferring pollen from a desirable plant to the stigma of another plant
Artificial Insemination
Involves transferring the semen from a favourable animal to the uterus of a female. It increases favourable traits but reduces genetic diversity
Cloning
Results in identical offspring (using cuttings, runners etc for plants) with favourable characteristics and can make copies of endangered species such as the Wollemi pine. Cloning animals does not have very high success rates and presents many ethical and health issues for the animals involved
Step 1 of Interphase
G1 - cellular contents excluding the chromosomes are duplicated
Step 2 of Interphase
Synthesis - each of the 46 chromosomes is duplicated
Step 3 of Interphase
G2 - Cell checks chromosomes for errors
Mitosis Step 1
Prophase - Chromatin material shortens and thickens by coiling and separates into chromosomes. Centrioles move to opposite ends of cell and spindle fibres form
Mitosis Step 2
Metaphase - Chromatids line up across the centre of cell and attach to spindle fibres
Mitosis Step 3
Anaphase - Sister chromatids seperate and move to opposite ends of the cell, each becoming a daughter chromosome with one copy of DNA
Mitosis Step Four
Telophase - Spindle fibre breaks down and the nuclear membrane and nucleolus reappear. Chromosomes loose their distinct shapes
Mitosis Step Five
Cytokinesis - The cell membrane pinches and divides the cytoplasm in half. This results is two identical daughter cells, each containing a complete copy of the original DNA and all organelles
Exons
Coding segments of eukaryotic DNA.
Polypeptide
A molecule made up of a chain of amino acids
Primary Structure
The basic structure of a protein, arranged as polymers of amino acids in a linear chain
Secondary Structure
3D arrangement of polypeptide chain created by folding or pleating, caused by hydrogen bonds making a backbone (e.g fibrous proteins)
Tertiary Structure
Created by attraction between folded and pleated polypeptides (e.g globular proteins)
Quaternary Structure
Made up of two or more polypeptide chains (folded or pleated) that are linked to create a complex but specific shape
Meiosis Step 1
Early Prophase - Chromosomes seperate into homologous pairs
Meiosis Step 2
Late Prophase - Nuclear membrane breaks down and crossing over (synapsis) occurs at the chiasma
Meiosis Step 3
Metaphase I - Chromosomes align in pairs and random segregation occurs (chromosomes seperate into random pairs so different combinations of paternal and maternal chromosome alignment are possible). Chromatids attach to spindle fibres
Meiosis Step 4
Anaphase I - Spindle fibres make chromosomes seperate and move to opposite ends of the cell
Meiosis Step 5
Telophase - Two daughter cells form and the chromosome number is halved
Meiosis Step 6
Cytokinesis I - New cell membrane is formed
Meiosis Step 7
Metaphase II - Chromosomes align at the equator
Meiosis Step 8
Anaphase II - Daughter chromosomes move apart to opposite poles
Meiosis Step 9
Cytokinesis II - Cells seperate and the final result is four daughter cells that are not genetically identical to each other and have half the original chromosome number
