Review for final. What are the properties of living things? (name 2) Made of cells Metabolism (take...

Post on 29-Dec-2015

214 views 0 download

Tags:

transcript

Review for final

What are the properties of living things? (name 2)• Made of cells

• Metabolism (take in/use energy)

• Grow

• Respond to environment

• Have internal structure

• Reproduce

• Change over time

What’s the difference between prokaryotic and eukaryotic cells?

• Eukaryotic cells have a nucleus and prokaryotic cells don’t

What are some benefits of bacteria? (name 2)• Made oxygen

• Decompose dead organisms

• Help us digest food

• Help us make certain foods

• Capture nitrogen and make it useable

• Environmental cleanup

• Manufacture of certain medicines

How should antibiotics be properly used?• Only for bacterial infections

• Use the whole course

• Use only when necessary

How are plant cells different from animal cells?• Cell wall

• chloroplasts

What is the equation for photosynthesis?

• Water + carbon dioxide + light energy

Glucose + oxygen

Remember, oxygen is a waste product for the plant, not the purpose of photosynthesis

What is the equation for cellular respiration?

• Glucose + oxygen water + carbon dioxide + ATP (useable energy)

• Remember, we breathe so we can make energy!

What organelle makes food?

• Chloroplasts--in plants, which make their own food

What organelle makes energy?

• Mitochondria—found in all eukaryotic cells

What organelle makes protein?

• ribosome

What does the cell membrane do?• Let some things into cells and keep other

things out of cells

How does diffusion work?

• Solute moves from high to low concentration, needing no energy

How does osmosis work?

• Water moves from high to low concentration

What is the difference between hypertonic, hypotonic, and isotonic?

• Hypertonic=higher concentration of solute, water will move in that direction

• Hypotonic=lower concentration of solute, water will move out of hypotonic and into hypertonic

• Isotonic=same concentration of solute

What is needed for photosynthesis to occur?• Carbon dioxide

• Water

• Chloroplasts

• Light

What is ATP?

• Usable energy for the cell

What is the purpose of DNA?

• The hereditary material

• The instructions for making proteins

What is DNA made of?

• Nucleotides—which are made of sugar, phosphate, and nitrogen bases

What are the 4 bases of DNA?

• Adenine, Guanine, Cytosine and Thymine

• A pairs with T, C pairs with G

How is RNA different from DNA?

1. Single strand instead of double

2. Uracil instead of Thymine

3. Ribose sugar instead of deoxyribose

4. Can leave the nucleus

Why do we need RNA?

• So DNA can stay in the nucleus and be safe—RNA is expendable and carries the DNA message out to the ribosomes

What is protein synthesis?

• DNA RNA protein

What is transcription and where does it take place?

• DNA RNA

• In the nucleus

Transcribe this DNA to RNA

• TGGCTCATTGAT

• ACC GAG UAA CUA

What is translation and where does it take place?

• RNA protein

• In the ribosomes

What is a codon?

• A three letter base sequence that stands for a particular amino acid

Translate this mRNA to amino acidsAUG CCA GGU ACU UGA

Start-pro-gly-thr-stop

What is a chromosome?

• A large molecule of DNA (and some proteins): each chromosome contains the DNA for thousands of genes

How many chromosomes do humans have?

• 46 – 22 pairs of homologous body chromosomes (autosomes) and one pair of sex chromosomes

What is the difference in male and female chromosomes?

• Males – XY

• Females – XX

When the body makes new cells, chromosomes copy themselves so that each cell has a full copy of DNA. Why does the body need to make new cells?

• Replace worn cells• Repair damaged cells• Growth• Asexual reproduction (in bacteria and other

prokaryotic cells)

What is the process of cell division to make new body cells called?

• Mitosis

What is the end product of mitosis?

• Two identical daughter cells

What are gametes?

• Eggs and sperm

What is cell division to produce gametes called?

• Meiosis

What is the end product of meiosis?

• Four genetically different gametes

How many chromosomes in human gametes?• 23—22 autosomes and one sex

chromosome (X in eggs and X or Y in sperm)

What is it called when there is an error in the DNA?

• Mutation

What is good about mutations?

• It could be beneficial to survival

• mutation is the ultimate source of all diversity on Earth

Mutations cause variation. What are other sources of variation?

• Crossing over during meiosis

• Independent assortment during meiosis

• Random selection of egg and sperm in sexual reproduction

• Remember, the big advantage of sexual reproduction is that it creates variation

What are the advantages of asexual reproduction?

• Don’t need a mate

• Can have lots of offspring really fast

• Take advantage of a stable environment

Proteins produce traits. What is a trait?

• A characteristic of an organism—can be physical, behavioral, internal, predisposition to medical condition

What is an allele?

• Different form of a gene, each allele produces a form of a particular trait

Explain dominant and recessive

• Dominant—the trait that shows, so only one allele is needed to produce it. Symbolized by capital letter.

• Recessive—the trait that is hidden, so only produced when organism has two recessive alleles. Symbolized by small letter

Explain homozygous and heterozygous

• Homozygous—both alleles are the same. Example: BB, bb

• Heterozygous—alleles are different. Example: Bb

Explain genotype and phenotype

• Genotype is what your two alleles are: Example—Bb

• Phenotype is your appearance: If B = brown eyes and b = blue eyes, Bb will have the phenotype brown

An individual heterozygous for the sickle cell gene (a carrier) has children with someone who has sickle cell. Draw the Punnett Square to find the probability that an offspring will have sickle cell.

A a a a

Aa aa

Aa aa

If two individuals who are heterozygous for sickle cell have children, what is the probability a child will have sickle cell? What is the probability he/she will be a carrier?

A a A a

AA Aa

Aa aa

Have it = ¼

Be a carrier = ½

What do you call this figure?

• A pedigree

What does shading mean?• Individual is affected

Is the trait dominant, recessive, or sex-linked?

• Recessive (children sick but parents don’t have it)

What is evolution?

• Genetic changes in populations of organisms over time

What is an adaptation?

• A genetic trait that helps an organism survive in a given environment

How does evolution work?

• Organisms have variation in their adaptations

• They compete for scarce resources and individuals with better adaptations tend to win and survive better

• They reproduce and pass their favorable adaptations on to their offspring

What is the evidence for evolution?

1. Artifical selection (dog example)2. Fossils of extinct organisms that are similar but

not identical to living species3. Homologous structures (like human arm,

whale flipper, bat wing)4. Vestigial organs (like human tailbone)5. DNA—the more closely related, the more alike

the DNA6. Embryo development (a few week old human

embryo looks the same as a lizard or pig)7. Direct observation