science in action 9 Unit A section 2 and 3

Heritable characteristics + examples

characteristics that are transmitted from generation to generation, such as eye colour

Non-heritable characteristics + examples

characteristics caused by the environment, such as tanned skin due to exposure to sunlight

Discrete variation

variation in a heritable characteristic that has an either/or form, such as either being albino or not being albino

Continuous variation

variation in a heritable characteristic that falls within a range, such as height

Asexual reproduction

reproduction without the fusion of sex cells, resulting in identical offspring to the parent

(only one parent)

what are the different forms of asexual reproduction? (4, vbsb)

binary fission, budding, spore production, and vegetative reproduction.

Binary Fission

a type of asexual reproduction in amoebas and other organisms, a parent cell divides exactly into two identical cells

Budding

a type of asexual reproduction a new organism develops from an outgrowth, or bud, on the parent

Spore Production

a cell produced by asexual reproduction in certain organisms such as ferns, which can develop directly into an adult

Vegetative Reproduction

a type of asexual reproduction in plants that does not involve the formation of a seed

Cutting

a cut piece of a plant that is used to reproduce that plant; cuttings usually have a part of the stem and a few leaves

Runners

long stems that grow along the soil of the surface and produce new plants

Tubers

Fat, underground stems capable of growing a new plant such as potatoes on a potato plant.

Bulb

underground stem covered with fleshy leaves from which daffodils and tulips develop

Sucker

new plants that are produced from the roots of the parent plant the roots of aspen trees

Sexual reproduction

reproduction involving the exchange of genetic material between two individuals resulting in offspring that are genetically different from the parents

gametes

a sex cell, either female or male, that can unite with another to form a fertilized cell (zygote) that can develop into a new individual

sperm cells

a male sex cell

egg cells (ova)

or ovum, a female sex cell

fertilization

the union of a female sex cell and a male sex cell (during mating)

zygote

a fertilized egg ( The cell created by the joining of the two gametes)

cleavage

the first divisions of a fertilized egg

embryo

an undeveloped organism in its beginning stages, which is possible through continued cell division.

Pollen

fine yellow powder on the anthers of flowers, consisting of grains that contain male sex cells (gametes) found on the stamen

stamen

the male part of a flower

Ovules

sac containing the female sex cells (gametes) of a plant

pistil

the female reproductive organ of a flower

Pollination

the transfer of pollen from anther to stigma (of the pistil)

anther

a part of the stamen that produces pollen and stores it

stigma

the female part of a flower, which receives pollen

Cross-pollination

the transfer of pollen from the anther of one plant to the stigma of another by wind, water, or animals

Cross-fertilization

the joining of a gamete from a pollen grain and a gamete from an ovule to form a zygote

style

the structure that supports the stigma and connects it with the ovary of a plant

ovary

female reproductive organ in which egg cells are produced; in plants, the structure contains the ovules

self pollination

when pollen is transferred from anther to stigma on the same plant

Genetics

The study of how characteristics of living things are passed from one geto another

DNA

Like a blueprint; is the inherited material responsible for variation

Chromosomes

The arranged form of DNA ; humans have 23 pairs

DNA molecule

Looks like a twisted ladder

Guanine

G - orange

Cytosine

C - blue

Adenine

A - green

Thiamine

T - violet

Genetic Code

Arrangement of chemicals in DNA that form a code that cells can read

Gene

Responsible for characteristics to traits, part of our DNA.

Allele

Different forms of a gene

Mitosis

Cell division that produces two identical offspring cells from one parent

Meiosis

Cell division that produces cell with only half a normal cell ; needs two cell divisions

Controlled Breeding

Mating organisms to produce offspring with certain traits

Traits

Characteristics of organisms

Purebred

the offspring of many generations that have the same traits

Hybrid

Offspring of crosses between parents with different traits

Genotype

Letters of the allele ; hh/HH/hH/Hh

Phenotype

An organism's physical appearance, or visible traits.

True breeding

Making a purebred

Dominant traits

The outward form observed when two opposite acting alleles are inherited

Recessive traits

The outward form observed only when two same acting non dominant alleles are inherited

Heterozygous

Two different genotypes

Homozygous

Both genotypes are the same

Incomplete dominance

Situation in which one allele is not completely dominant over another allele