Biology (B6) Flashcards by Laaibah Majid

What type of cell division is used for asexual reproduction?

Mitosis

How well did you know this?

Not at all

Perfectly

Define asexual reproduction

Asexual reproduction involves one parent organism having genetically identical offspring

How well did you know this?

Not at all

Perfectly

What can we call genetically identical offspring?

Clones

How well did you know this?

Not at all

Perfectly

Define sexual reproduction

Sexual reproduction usually involves two parent organisms which produce genetically different offspring

How well did you know this?

Not at all

Perfectly

What are the 2 animal gametes?

Sperm cell and egg cell

How well did you know this?

Not at all

Perfectly

What are the 2 plant gametes?

Pollen and Ovum

How well did you know this?

Not at all

Perfectly

Describe the structure of DNA

Double helix, polymer

How well did you know this?

Not at all

Perfectly

What is a gene?

A short section of DNA that codes for the production of a specific protein

How well did you know this?

Not at all

Perfectly

What is a chromosome?

A long coiled molecule of DNA

How well did you know this?

Not at all

Perfectly

How many chromosomes are found in a human body cell?

46 or 23 pairs

How well did you know this?

Not at all

Perfectly

How many chromosomes are found in a human gamete?

How well did you know this?

Not at all

Perfectly

What is the monomer that makes up DNA called?

A nucleotide

How well did you know this?

Not at all

Perfectly

What 3 parts make up a nucleotide?

Phosphate, Pentose sugar, base

How well did you know this?

Not at all

Perfectly

What are the complementary base pairs in DNA?

A-T and C-G

How well did you know this?

Not at all

Perfectly

Describe the stages of transcription

An enzyme attaches to DNA at the start of the gene
2.DNA unzips which breaks hydrogen bonds
The exposed bases on the coding strand are now used to make a copy
4.Bases pair according to the complementary base pairing rule (A-U and C-G)
5.This new copy is called mRNA
6.mRNA is small enough to leave the nucleus through the pore and go to the ribosome
The enzyme detaches and the DNA molecules zips back up

How well did you know this?

Not at all

Perfectly

What is a mutation?

A change in the DNA base sequence

How well did you know this?

Not at all

Perfectly

What is meant by the word genome?

The entire genetic material of taht organism

How well did you know this?

Not at all

Perfectly

Name a benefit of the human genome project?

-Knowledge of genes that link to diseases
-Understanding and treatment of inherited disorders
-Tracing human migration patterns from the past

How well did you know this?

Not at all

Perfectly

What is the purpose of meiosis?

To produce gametes that are genetically different from each other

How many divisions happen in meiosis?

2 divisions

How many cells are formed in meiosis?

Are the cells produce in meiosis haploid or diploid?

Haploid

What does it mean if a cell is haploid?

Contain half the amount of chromosomes

Where does meiosis occur?

In the sex organs (testis and ovaries)

What is an allele?

A different version of the same gene

How do we represent a dominant allele?

Capital letter

How many copies of a recessive allele are needed for that characteristic to be displayed?

2 copiees

Describe the following genotypes: Bb BB bb

Heterozygous Homozygous dominant Homozygous recessive

Define phenotype

The physical properties of a person

Are the following characteristics influenced bu genetics only, environment only or both? Weight Eye colour Scar

Both Genetics Environment

What is the difference between Dis-continuous and Continuous data?

Dis-continuous- Data which fits into groups or categories Continuous- Can take any value within a range

What are the stages of selective breeding

Select parents with desired characteristics. Breed them together. Pick offspring with the desired characteristic and breed together. Repeat over many generations, until all the organism have the desired characteristic

Give a disadvantage of selective breeding

* May lead to inbreeding – can cause health problems in species * Accumulation of harmful recessive characteristics * Reduction in variation/gene pool

What is genetic engineering?

The deliberate modification of the characteristics of an organism by manipulating its genetic material

What are the stages in the procedure for genetic engineering?

Cut the desired gene out of one organism Put it into the DNA of another organism to get the desired characteristics. Using enzymes

Name a problem/disadvantage of genetic engineering

· Reduces biodiversity · Affects food chains · Pests become resistant

What are the stages in natural selection?

V - all organisms show variation / mutation causes variation I- Organisms inherit the allele C – Competition for survival – those with the advantageous allele outcompete and therefore R - they reproduce A - pass on the alleles for advantageous characteristic M – over many generations the frequency of the advantageous allele increases in the population

Define a species

Organisms that reproduce together to form fertile offspring

How can a species arise?

Through geographical isolation

Who developed the theory of natural selection?

Charles Darwin

How do fossils form?

Fossils are formed when animal and plant remains are preserved in rocks and replaced by minerals

What are some issues with using fossils as eveidence of evolution?

Gap in fossil records/ not all been discovered

What is classification?

Classifications id the process of sorting living things into groups, that share similar features

Why do scientists classify organisms?

1) Identify species 2) Predict characteristics 3) Find or show evolutionary links

What are the 5 kingdoms?

Animals, Plants, Fungi, protists and prokaryotes

What are the 7 grouping order, starting with kingdom?

Kingdom, Phylum, Class, Order, Family, Genus and species

What does the binomial name of an organism include?

Genus and Species