Bio 1 Midterm 2

\
 Describe the main pigments found in plants (chlorophylls and carotenoids), including the light wavelengths that absorb and REFLECT

\
Chlorophylls A and B are the main pigments and absorb blue and red light, while they reflect Violet and orange for A and Blue and yellow for B. While Carotenoids absorb violet and blue-green light while reflecting yellow orange and red 

What goes in and what comes out of the stomata?

\
They take in Carbon dioxide and Release Oxygen 

What donates electrons to photosystem II in the light reactions? What are the products of the light reactions (i.e. the the main purpose of the light reactions)? 

\
Chlorophyll donates electrons to photosystem II. The purpose of Light reactions is to capture energy from sunlight, which changes and creates chemical energy. 

\
What is the product of the Calvin cycle (i.e. the main purpose of the Calvin Cycle), and what enzyme fixes carbon from carbon dioxide in the Calvin cycle? 

\
The purpose of the Calvin Cycle is to turn carbon dioxide from the air into sugar, the food autotrophs the need to grow. Rubisco fixes carbon from C02 in the cycle 

What is photorespiration, and how have some plants (C4 and CAM) adapted to avoid photorespiration? How might Do these adaptations help C4 and CAM plans during a period of global warming

The process that occurs in the Calvin Cycle during plant Metabolism. By using another enzyme called PEP during the first step of carbon fixation. As a result, they thrive on long growing seasons with lots of access of sunlight.   

What is a Photon?

is a quantum of radiant energy with visible wavelengths

What is a Pigment?

Molecules that can absorb and reflect wavelengths of light

What is Chlorophyll a and b (primary photosynthetic pigments)

\
A is the primary photosynthetic pigment. B is a secondary pigment. Presented in all plants, algae, bacteria, etc 

What is Carotenoids (secondary photosynthetic

pigments)

tetraterpene pigments, which exhibit yellow, orange, red and purple colors

What is a Stomata?

 Fluid inside chloroplasts; similar to cytoplasm

What is Chloroplasts?

\
 Organelles in photosynthetic organisms where photosynthesis occurs

What is Thylakoids

\
 membranes within the chloroplasts where photosynthetic pigments are housed 

What is Stroma?

\
 They are pores in the shoot epidermis of plants

What are Light reactions?

electrons from water are excited by solar energy and used to power the fermentation of ATP and NADPH (electron carrier)

What is the Calvin Cycle?

\
energy from light reactions (ATP and NADPH) used to convert carbon dioxide to glucose. 

What is Rubisco?

(enzyme) combines three molecules of carbon dioxide with three molecules of the sugar, RuBP, creating a 6- carbon molecule; that's called carbon fixation

What is Photorespiration?

process in which the enzyme rubisco binds with oxygen instead of carbon dioxide when CO2 levels in the plant are low

What is PEP carboxylase?

\
 a protein that binds CO2 and holds on to it until it is needed by rubisco in the Calvin Cycle; helps rescue water loss in C4 and CAM plants

\
What are the two types of vascular tissues found in plants, and what does each type of tissue transport? 

Two types of vascular tissues are the xylem and phloem. The xylem transports water and dissolved minerals from the roots and leaves. Phloem transports carbohydrates.

 What are the functions of roots, stems, and leaves?

\
Roots absorb water and minerals from the soil and anchor the plant to the ground. Stems support the plant above ground and carry water to the leaves. Leaves are the main area where photosynthesis takes place 

\
What is a seed, and what are the functions of the different parts of a seed (seed coat, cotyledons, endosperm)? 

\
The seed is the embryonic stage of the plant in the life cycle. The  Seed coat is used to improve the establishment process. The cotyledon helps the seed supply the nutrition of the plant embryo.  The endosperm surrounds and nourished the embryo in the seeds of angiosperms (flowering plants) 

\
What is pollination? Why have flowers evolved to look the way they do? How is pollination different between gymnosperms and angiosperms?

\
The transfer of pollen to a stigma, ovule, flower, or plant to allow fertilization. Flowers have evolved due to pollinators affecting one another’s reproductive success. Pollination is from the different animals that use it, while both gymnosperms and angiosperms are wind-pollinted.

What is transpiration, and how is it involved in water transport in plants (cohesion-tension hypothesis)?

\
it is the evaporation of water from plants. It is moved by the negative pressure generated by the evaporation of water from leaves

\
What adaptations have plants evolved to reduce water loss via transpiration?

\
One adaption is that Leaves are covered by a waxy cuticle on the outer surface that prevents the loss of water. 

What is Phylogenetic tree?

 diagram showing evolutionary relationships among organisms

What is Spores?

\
 asexual reproduce, a packed of plant cells capable of growing into a new plant only in a moist environment 

What is Vascular tissue?

\
 complex conduction tissues in higher plants that are made up of different types of cells and elements 

What is Xylem?

 moves up water up a plant

What is Phloem?

\
 moves up food up or down a plant for storage

What is a Stem?

Produces leaves, branches, and flowers, transports nutrients and water from roots to leaves, provides structural support

What is a leaf?

 primary location for photosynthesis

What is a Bud (axillary)?

 undeveloped shoots that can form new branches or flowers

What is a Root (Root system)?

\
anchors plant, absorbs minerals and water, and stores excesses  carbohydrates

What is root hairs?

 Increase surface area for absorption of water and nutrients.

What is Mycorrhizae?

a symbiotic relationship between a fungus and plant roots

What is a Seed?

\
a plant embryo and its food supply inside a protective layer (seed coat) much more successful than spores 

What is a Flower?

\
sexual reproductive structure of angiosperms

What is a Fruit?

 enclosed the seed, attracts seed dispersers, and can provide more nutrition for germinating seed

What is a Vegetative propagation?

\
 a method of sexual reproduction in plants, where a root stem or leaf is used to grow a new plant. 

What is Transpiration?

\
loss of water from leaves and stems by diffusion (osmosis) and or evaporation

•What is Deoxyribonucleic acid (DNA), and what is it made up of?

the molecule that carries the genetic information for the development and functioning of an organismDNA is made up of four building blocks called nucleotides: Adenine (A), Thymine (T), guanine(G), and cytosine ((C)).

Which nitrogenous bases are always paired together?

\
Adenine pairs with Thymine, while Guanine (G) pairs with Cytosine ((C)). 

•How many chromosomes do humans have, and how many pairs are they arranged in?

\
We have 23 pairs of chromosomes, 23 pairs of chromosomes

What is the difference between haploid and diploid cells?

Haploid cells refer to the presence of a single set of chromosomes in the cells of an organism. Diploids are sexually reproducing organisms from having two sets of chromosomes (one from each parent).

\
Which cells in our bodies are haploid, and which cells are diploid? Why is it important for gametes to be haploid?

\
Hapoliod is egg and sperm cells, while diploid is most cells in our bodies. The reason that gametes have to be haploid is due to the amount of DNA so that at fertilization when the egg and sperm combine it results in a cell with a full complement of DNA. 

What enzymes are involved in DNA replication, and what are their functions?

DNA Helicase: Unwinds double helix by breaking down bonds(H20)

RNA primase: Builds an RNA primer on leading and lagging strands 

DNA polymerase: Adds daughter nucleotides on parent strands

DNA ligase: Joins Okazaki fragments to form cont. strand

\
What are the different phases of the cell cycle, including interphase (G1, S, and G2) and mitosis (Prophase,Metaphase, Anaphase, Telophase, Cytokinesis)? Briefly describe what occurs during each phase. 

 **Cell Cycle**: G1(Cell growth) S (DNA Synthesis) and G2 (cell growth)

\
**Mitosis**: Prophase: chromosomes shorten and thicken, Metaphase: chromosomes line up in the middle of the cell, Anaphase: Chromatids break apart and move opposite ways, Telophase:Two nuclei formed after envelopes reform, Cytokinesis: splits cells into two cells

How is cytokinesis different between plant and animal cells?

**Plant Cytokinesis**: starts in the center of the cell and moves toward the cell wall

**Animal Cyokinesis**: starts at the edges of the cell in the plasma membrane and moves towards the center 

\
What is cancer? What are the four characteristics of cancer cells? 

\
Cancer is a disease in which some of the body’s cells grow uncontrollably and spread to other parts of the body. Some characteristics include: Grow and dividing at an abnormally rapid rate, having abnormal membranes, cytoskeletal proteins, and morphology

What is the difference between benign and malignant tumors?

Begin: grow slowly and do not spread

Malignant: tumors can grow rapidly, and destroy tissues

\
How is cancer treated by doctors?

\
Treated by Chemotherapy, radiation, and surgery

What is Nucleotide?

nitrogenous base attached to five-carbon sugar (deoxyribose or ribose) and a phosphate molecule

What is a Gene?

a specific section of DNA

What is a Chromatin?

a linear strand of DNA wrapped around histones

What is a Histone

\
 proteins that keep DNA from getting tangled

What is a Chromosome?

 a compact strand of DNA the form takes place during mitosis

What is the Genome?

complete collection of an organism's genetic information all 46 chromosomes

What is Karyotype?

\
 pictorial arrangement of chromosomes in their homologous pairs 

What is a Diploid?

\
cells with two copies of each chromosome (46 total) 

What is a Haploid?

 cells with a single copy of a chromosome (23 total)

What is Gametes?

\
 sex cells (egg and sperm) 

What are somatic cells?

\
 cells in the body other than sperm and eggs

What is Mitosis?

division of parent cells nucleus and chromosomes

What is Cytokinesis?

Cell splitting

What is Cleavage furrow?

\
 the indentation of the cell’s surface that begins the progression of cleave

What is cell plate?

\
a disk-like structure in the plane of the equator of the spindle that separates the two sets of chromosomes during cytokinesis

What is Spindle fibers?

Microtubules that pull apart sister chromatids and take them to opposite ends of the parent cell, allowing the cell to divide down the middle

What is cancer?

\
 Unregulated multiplication of cells, which invade nearby tissues or other parts of the body, destroying working tissues

What is Benign tumor?

tumor cells that may continue to divide but are not  invasive

What is a Malignant tumor?

\
tumor cells that divide and spread to adjacent tissues through distant tissues through lymphatic vessels and blood vessels. 

\
What are the differences between mitosis and meiosis concerning the number of daughter cells, if the daughter cells are haploid or diploid, the number of cell divisions, the type of cells going through meiosis and mitosis, and whether or not genetic diversity is increased as a result of each process? 

\
Mitosis results in two identical daughter cells (diploid) and involves the division of body cells, whereas meiosis results in sex cells(Haploid) it involves the division of sex cells

\
What happens during the two processes that increase genetic variation in meiosis (crossing over and independent assortment), and how is genetic variation increased thanks to these processes?

\
Each gamete contains a different set of DNA,it is increased due to meiosis because of recombination and independent assortment in miosis that each set contains a different set of DNA

What sex chromosomes do females have, and which ones do males have? How are these chromosomes different?

\
Males have XY sex chromosomes, while females have XX sex chromosomes. They are different due to the fact that Females have 2 x chromosomes and males only have one x chromosome. 

\
What are the main differences between male and female gametes in humans? Which parent’s gamete determines the sex of the child? 

\
Male gametes are known as sperms and are produced by the process of spermatogenesis, while female gametes are known as the egg and are produced by oogenesis. Male parent contributes to determining the child's sex. 

\
What happens during fertilization, and what is the product of this process? How does the product of fertilization develop into an embryo? 

\
The sperm and egg unite in one of the fallopian tubes to form a zygote, which travels down the fallopian tube, once it reaches the uterus it becomes a blastocyst and burrows into the uterine ling process called implication. The implicated blastocyst continues its development into an embryo and then a fetus is created.

\
* What are the differences between identical and fraternal twins? Why don’t fraternal twins look like each other?

Identical twins share the same genomes and are always the same sex, while fraternal twins result in the fertilization of two separate eggs with two different sperms. It's due to the different eggs they are from, giving them different genes and traits.

What is Meiosis?

\
division of a cell into two genetically identical daughter cells; used in asexual reproduction

What is Zygote?

\
the first cell of a new organism, formed when the sperm and egg fuse together during fertilization

Homologous chromosomes

chromosomes that are the same in function and size

What is tetrad?

\
 pair of homologous chromosomes after replication

What is crossing over?

\
 process in which homologous chromosomes exchange reciprocal portions of themselves during prophase 1

What is independent assortment?

\
the random distribution of homologous chromosome pairings during metaphase 1

What is sex chromosomes?

 determine the sex of an organism

What is Autosomes?

\
 non-sex chromosomes responsible for forming all parts of an organism except sex organs and hormones 

What is Semen?

continues sperm cells, as well as nutrients, lubricant, and ph Buffer

What is Spermatogonium?

\
sperm cells develop from spermatogonia that undergo meiosis in the testes

What is Oogonium?

\
eggs multiply by mitosis when the female fetus is developing 

•What are the differences between DNA and RNA concerning the number of strands and the nucleotides associated with each nucleic acid?

 DNA is a double-stranded molecule that has a long chain of nucleotides. In contrast, RNA is a single-stranded molecule that has a short chain of nucleotides.

\
 What are the main functions of each molecule?

\
DNA carries genetic information which reads cells in creating proteins. At the same time, RNA acts as a template for making proteins. 

\
What is the purpose of transcription and translation? Where does each process occur (nucleus or cytoplasm)? 

\
The purpose is to make all proteins the body needs to function from information stored in the sequence of bases in DNA. Transcription occurs in the nucleus and translation occurs in the cytoplasm. 

Know how to convert a DNA sequence to an mRNA sequence (transcription) and then to an amino acid sequence (translation). 

\
Remember: **DNA: ATGC RNA: AUGC** (the only thing that changes is T to U), to convert DNA to mRNA it just converts DNA to RNA

What are the different types of RNA and their functions?

 mRNA is between the nucleus where proteins are made. rRNA and tRNA are involved in protein synthesis.

\
What are the three binding sites in the ribosome, and what occurs at each binding site? 

 The three sites are **A (aminoacyl)** site which accepts incoming aminoacylated. **P (peptidyl)** site which holds tRNA with the nascent peptide chain; and **E(exit)** site, which holds the deacylated tRNA before it leaves the ribosome.

\
What is a mutation? What is the difference between a point mutation and a frameshift mutation? 

\
any change in the DNA sequence of the cell, Point mutations involve the replacement of one base with another frame-shift mutation occurs when a bast is added or removed from the sequence

What is artificial selection, and how are artificially selected organisms different from genetically modified organisms?

\
Artificial selection is the process that selects individuals with desirable traits to breed. In artificial selection, scientists breed only individuals that have desirable traits

\
What are some of the reasons why GMOs are controversial? 

Some key reasons that they are related to genetically modified food, they reduce biodiversity, threaten the future of small-scale farming, and also reduced the food security for the world's poorest people.

What is DNA?

primary information storing molecule in living organisms

What is RNA?

 transfers genetic code from DNA in the nucleus to protein-forming system ribosomes in the cytoplasm

What is transcription?

the process by which a genes base sequence is converted to mRNA

What is translation?

 the process by which mRNA directs the production of a protein