Science - Biology Pt.2 Flashcards
yeast cells reproduce by ….
hydra reproduce by…
budding
-new organism develops from an outgrowth or bud due to cell division at one particular site.
bread mould…
spore production
- reproductive cells that must fuse in pairs in order to give rise to a new individual.
- usually haploid and unicellular and are produced by meiosis
e.coli by…
binary fission
- an organism duplicates its genetic material, or deoxyribonucleic acid (DNA), and then divides into two parts (cytokinesis), with each new organism receiving one copy of DNA.
multiply plant growth by…
vegetative propagation
- form of asexual reproduction in plants. It is a process by which new organisms arise without production of seeds or spores.
- New plants grow from parts of the parent plant.
piece of plant or animal is made into a new organism by…
regeneration
- renewal through the internal processes of a body or system.
ovulation
mature ovarian follicle discharges an egg. egg travels down Fallopian tube where it might be met by a sperm and fertilised
menstruation
body sheds the lining of the uterus when not fertilised.
menstrual blood flows from uterus, through cervix and passes through vagina
fertilisation
process which an egg and sperm cell fuse together to form a zygote (development of a new individual organism)
embryo
an unborn or unhatched offspring in the process of development
gestation
the process or period of developing inside the womb between conception and birth.
life first took form was….
protozoa
organisms have how many cells?
1
cilia
hairs covering cells which make movement possible
low ph in vagina protects from..
infections and bacteria
DNA is the …..
only subsance in the world which has capability to reproduce itself indentically
how long is ovum susceptible to fertilisation?
24hrs
how long can sperm survive?
5 days
sperm production functions best at?
35 degrees
below normal body temperature
where is sperm stored?
epididymus
DNA bases
Adenine Cytosine Guanine Thymine - each word is called a codon, and codes for pieces of protein are called amino acids
amino acids
join together in a chain to form a protein which determine something about you (genes, characteristic)
mitosis stages
interphase 1. prophase 2. metaphase 3. anaphase 4. telophase cytokinesis
interphase
- replicates its DNA in preparation for mitosis.
- spends 90% of its time in interphase, 10% in mitosis
prophase
- chromosomes are condensing due to full replication into double rod-shaped structures called chromosomes in which the chromatin becomes visible.
- the start of interphase (BEGINS)
metaphase
- nucleas (edge) dissolves - disassembled
- chromesome pairs line up
separates duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells.
anaphase
- chromosomes move to the opposite sides of the cells
-spindles (fiber) pulls chromosome to the end
replicated chromosomes are split and the daughter chromatids are moved to opposite poles of the cell.
telophase
- new nuclei form on the side surrounding chromosomes
- break apart
The small nuclear vesicles in the cell begin to re-form around the group of chromosomes at each end.
cytokinesis
- division of cytoplasm (pinching of cell into 2)
physical process - divides the cytoplasm of a parental cell into two daughter cells
mitosis
- fertilised egg undergoes mitosis
- divides into 2 smaller identical cells
- same chemical code within their nucleus which are made of DNA
meiosis
process where a single cell divides twice to produce four cells containing half the original amount of genetic information
- sperm and eggs (gametes) need to be formed by meiosis process
- forms gametes with 23 chromosomes (1 from each parent)
- occurs in the testes and ovaries
meiosis differs from mitosis in which ways?
- divides twice (PMAT twice)
- not identical to each other (non-identical cells)
- 23 chromosomes (instead of 46)
- splits into 4 cells (instead of 2)
homologous chromosomes
are a set of one maternal and one paternal chromosomes that pair up with each other inside a cell during meiosis.
- one from each parent
- about the same size
- contain the same types of genes in same location
partial dominance
phenotype of the heterozygous phenotype is distinct from and often intermediate to the phenotypes of the homozygous phenotypes.
- eg red and white flower cross = pink offspring
co dominance
occurs when the contributions of both alleles are visible in the phenotype.
- For example, in co-dominance, a red homozygous flower and a white homozygous flower will produce offspring that have red and white spots
pedigree
table or chart recording a line of ancestors
- the record of descent of an animal, showing it to be pure-bred.
hybrid
offspring that are the result of mating between two genetically different kinds of parents
sexual (reproduction)
reproduction where two morphologically distinct types of specialized reproductive cells called gametes fuse together, involving a female’s large ovum (or egg) and a male’s smaller sperm.
- two individuals produce offspring with genetic traits from both parents
