Cellmembrane and function

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Worksheet chapter-5 Cellmembrane and function
I. Choose the correct answer: (0.25 points each)
1. Channel proteins that allow water to pass through them are called _________
a. Glycoprotein’s c. Aqua proteins
b. Gap junctions d. Desmosomes
2. Osmosis means ___________________________.
a. Movement of water c. movement of solute
b. Movement of solution d. neither of them
3. If a cell is placed in a Isotonic solution, the cell will _________
a. swell c. shrink
b. remain the same d. none of the above
4. If a cell is placed in a hypotonic solution, the cell will ___ _____
a. swell c. shrink
b. remain the same d. none of the above
5. The fluid mosaic membrane describes the membrane as
a. containing a huge quantity of water in the interior
b. composed of fluid phospholipids on outside and proteins on inside
c. composed on protein outside and fluid phospholipid inside
d. made of proteins and lipids that can freely move
6. Which of the following is not a mechanism for bringing material into the cell?
a. Exocytosis c. Pinocytosis
b. Endocytosis d. Phagocytosis
7. Which of these types of cellular transport requires energy
a. facilitated diffusion c. osmosis
b. Active transport d. a and b
8. What chemical property characterizes the interior of the phospholipid bilayer
a. It is hydrophobic c. IT is polar
b.it is hydrophilic d.it is saturated
9. If someone at the other end of a restaurant smokes a cigarette, you may breathe in some smoke. The movement of smoke is similar to what type of transport.
a. osmosis c. diffusion
b. facilitated diffusion d. active transport
10. plasma membrane is made up of a ________
a. lipid layer c. lipid bilayer
b. phospholipid layer d. phospholipid bilayer
II. Answer whether true or false: (0.25 points each)
1. Diffusion is movement of water from a region of low concentration to a region of high concentration. ( )
2. If phagocytosis means eating solid particles, pinocytosis means drinking solid particles. ( )
3. In plant, cell to cell connection is due to the presence of plamodesmata. ( )
4. A membrane that allows certain things to pass through it and prevents certain things to pass is called permeable membrane. ( )
5. Gradient means a physical difference such as temperature, pressure, concentration etc between two regions. ( )
III. Choose any three questions and Write any four differences between them (each question 1 point).
1. Identify the picture and explain the process in few points
2. The picture shows human red blood cell in different solutions. Explain what happens to the cell in each solution
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3. Active transport and passive transport
4.Simple diffusion and facilitated diffusion
5.Define hypotonic, hypertonic, and isotonic. What would be the fate of an animal cell immersed in each of these three types of solution?
6. Briefly write about the structure and function of plasma membrane.

INTRODUCTORY BIOLOGY (BIOL-1411)

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INTRODUCTORY BIOLOGY (BIOL-1411)

FLL SEMESTER-2014
I. Choose the right answer:
1. Bacteria divides to produce daughter cells by the process of _________
a. Mitosis c. Binary fission
b. Meiosis d. None of them
2. During meiosis gametes produced have _________number of chromosome.
a. Diploid c. both of them
b. Haploid d. None of them
3. Sister chromatids are aligned in the centre of the cell during _________stage
a. Prophase c. Telophase
b. Metaphase d. Anaphase
4. Chromosomes attach to fibers at structures called __________________.
a. Telomeres c. Centromeres
b. Genes d. neither of them
5. Which of the following is not a function of mitosis in humans?
a. Repair of wounds c. Production of gametes
b. growth d. Replacement of lost cells
6. A biochemist measures the amount of DNA in cells growing in the lab. The quantity of DNA in a cell would be found double
a. Between prophase and anaphase c. Between metaphase and telophase
b. between G1 and G2 of cell cycle d. during M phase of cell cycle
7. In comparing somatic cells and gametes, somatic cells are
a. diploid with half the number of chromosomes
b. haploid with half the number of chromosomes
c. diploid with twice the number of chromosomes
d. haploid with twice the number of chromosomes
8. What are homologous chromosomes?
a. two halves of a replicated chromosomes
b, two identical chromosomes from one parent
c. two identical chromosomes, one from each parent
d. Two similar chromosomes, one from each parent.
9. Duplicated chromosomes consist of two identical DNA double helices, called __________.
a. Homologous c. Sister Chromatids
b. Chromatin strands d. neither of them
II. Answer whether true or false: (0.25 points each)
1. Diploid means n chromosomes and haploid means 2n chromosomes.
2. If an intestinal cell in a dog contains 78 chromosomes, a dog sperm cell would contain ______chromosomes
3. A micrograph of a dividing mouse cell shows 19 chromosomes each consisting of two sister chromatids. During which stage of meiosis could this picture be taken,
4. Meiosis is a cell division that occurs only in sex cells
5. Prophase is the last stage in mitosis where the two daughter cells separate
6. Cell cycle involves the G1, S and G2 phase only.
7. Cytokinesis in plant cells takes place by the formation of cell plate
8. Movement of sister chromatids to the same pole occurs in meiosis.
9. During meiosis there is only one round of replication for two divisions
10. Gametes are diploid with double the number of chromosomes
III. Answer any four of the following ( each carries 1.5 mark)
1. Diagram and describe the eukaryotic cell cycle. Name the various phases, and briefly describe the events that occur during each.
 
LABEL THE PARTS FROM PRESENTATION OR TEXT
1. Eukaryotic cell cycle is divided into two major phases: interphase and cell division
2. Interphase is the stage where the cell acquires nutrients from its environment, grows and duplicates its chromosomes it contains three sub phases
G1_ a newly formed daughter cell enters this stage, and carries out activities like: it grows in size, specializes to perform specific function and it decides whether to divide or not, and enters the next phase
S-phase: DNA synthesis takes place via semiconservative replication
G2: cell grows some more and then synthesize the proteins needed for cell division.
Cell division: cell carries out either mitosis or meiosis’ in order to form new daughter cells
2. Explain the process of Mitosis.
Mitosis consists of nuclear division followed by cytoplasmic division.
Mitosis occurs in the following phases
1: Prophase is the first phase, duplicated chromosome condense, spindle microtubules form , chromosomes are captured by microtubules
2 : Metaphase – duplicated chromosome are connected to spindle fibers leading to opposite poles of the cell. Microtubules shorted and lengthen until each chromosome lines up along the equator of the cell
3: Anaphase- sister chromatids formed during S-phase separates becoming independent daughter chromosomes, one of the 2 daughter chromosomes from each original parental chromosomes move to each pole of the cell
4: telophase- spindle fibers disintegrate nuclear envelope forms around each group of chromosome. The DNA revert to its original extended state, nucleoli begin to form
5: cytokinesis- microfilaments attached to membrane form a ring around the equator of the cell, constricts dividing the cell, in plants cell plate is formed forming 2 daughter cells
3. Compare the process of cytokinesis in plant cell and animal cell.
Cytokinesis in animal cells
a. Microfilaments attached to the plasma membrane form a ring around the equator of a cell . The ring contracts and constricts the cell’s equator
b. Eventually, contraction of the ring pinches off the membrane, forming two daughter cells, each with a nucleus identical with the other
c. Following cytokinesis, animal cells enter G1 of interphase, thus completing the cell cycle
Cytokinesis in plant cells
a. Stiff plant cell walls prevent the “pinching off” of cytokinesis seen in animal cells, which only have a plasma membrane
b. Instead, carbohydrate-filled vesicles assemble along the cell’s equator, between the daughter nuclei
c.The vesicles fuse into a continuous flattened sac, surrounded by plasma membrane and filled with sticky carbohydrates .This is called a cell plate
d. The plasma membranes of the plate fuse with the plasma membrane of the cell, forming two cells, with the carbohydrate in between becoming part of the cell wall
e. As in animals, plant cells enter G1 of interphase following cytokinesis, thus completing the cell cycle
4. Describe in humans the three categories of cells, based on their ability to divide and differentiate
1.Stem cells :
– have two important characteristics: self-renewal, and the ability to differentiate into a variety of cell types
-Stem cells self-renew because they retain the ability to divide, perhaps for the entire life of the organism
-Some stem cells in early embryos can produce any of the specialized cell types of the entire body
2.Other cells capable of dividing
-Some cells other than stem cells are capable of continuing to divide, but typically differentiate into only one or two different cell types
· Dividing liver cells, for example, can only become more liver cells
3. Permanently differentiated cells
· Permanently differentiated cells differentiate and never divide again
· For example, most heart and brain cells cannot divide
5. Complete the following table to compare mitosis and meiosis

mitosis Meiosis
a. Number of chromosomal duplications
b. Number of cell divisions
c. Number of daughter cells produced
d. Number of chromosomes in daughter cells
e. How chromosomes line up during metaphase
f. Genetic relationship of daughter cells to parent cells
g. functions performed in the human body

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Genetic problems

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Genetic problems: Must do 3 to 7

You can choose to do 1, and 2 or just 8 total number of genetic problems should be 6

1. Create a Punnett Square for a heterozygous individual (a+/a) crossed with a heterozygous individual (a+/a). In this case, the mutation is recessive.

Determine the genotypic ratio and phenotypic ratio.

For phenotypic ratio do not refer to specific a+ or a phenotype but instead refer to them as dominant or recessive.

2. Create a Punnett Square for a heterozygous individual crossed with a heterozygous individual.

Make the mutation dominant. Notice that the phenotypic ratio for dominant/recessive is identical to Q1 (3/4 Dominant, 1/4 recessive) except you now have to realize your mutation is Dominant, and wild-type is recessive.

3. You and your spouse have no children. You stand to inherit a sizeable fortune from your crazy Uncle Irving if you can produce three daughters in your family of three children. What is the probability of doing just that?

4. If you could convince Uncle Irving that simply having three children all of the same sex would do, then what would be the probability of your receiving the inheritance?

5. In quest of the family stipulated in #4 above, you produce a boy as your first child. Now, what is the probability of inheriting the fortune?

6. Why are the answers to #4 and #5 the same?

7. Finally, you have convinced Uncle Irving that you will agree to try for at least three girls out of four children. How likely are you to become wealthy given those conditions?

8. Research has shown that a particular eye defect is represented in a family pedigree as follows: A B C

a. By this data, which of the following mechanisms of inheritance are POSSIBLE? Autosomal dominant, autosomal recessive, sex-linked dominant, sex-linked recessive, Y-linked.

b. What is the most PROBABLE mechanism of inheritance?

c. What is the genotype of female A?

d. What is the genotype of male B?

e. What is the probability that a child from marriage C will show this eye defect?

Pharmaceuticals in the water are being blamed for severe reproductive problems in many types of fish

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Midterm question 5

“Pharmaceuticals in the water are being blamed for severe reproductive problems in many types of fish: The endangered razorback sucker and male fathead minnow have been found with lower sperm counts and damaged sperm; some walleyes and male carp have become what are called feminized fish, producing egg yolk proteins typically made only by females.

Meanwhile, female fish have developed male genital organs. Also, there are skewed sex ratios in some aquatic populations, and sexually abnormal bass that produce cells for both sperm and eggs”.

There are problems with other wildlife as well: kidney failure in vultures, impaired reproduction in mussels, or inhibited growth in algae.”

After reading the above paragraph, a population fish is decreasing every year.  Flushing medicine down the toilet is an action that has produced changes in the marine ecosystem. You are the company’s chemist responding to a government finding about pharmaceuticals contaminating the fishing waterways of NJ.

What design possibilities might save the marine ecosystem?  What tests could you use to indicate what macromolecules are overly abundant in the water system?

What macromolecules are responsible?  Why are these kinds of macromolecules responsible for feminizing fish? 

Create a PowerPoint presentation of 25 slides to convince the FDA that you have a possible solution.

USE APA formatting style and APA references including APA in-text citations, any image must be sited on the slide as well on the APA Reference slide.

Title page slide and Reference slide(s) are not part of the 25 slide count.