Start New Topic
  
  
  
Top Posters
Since Sunday
32
14
14
14
13
13
13
13
12
11
11
11
A free membership is required to access uploaded content. Login or Register.
HW 02- Animal Form & Function Part23
Uploaded: A year ago
Contributor: bio_man
Category: Biology
Type: Solutions
Rating: N/A
Filename:   HW 02- Animal Form & Function_Part23.pdf (1.08 MB)
Page Count: 10
Credit Cost: 2
Views: 1987
Last Download: N/A
Transcript
HW 02: Animal Form & Function 5/13/15 4:53 PM the gray crescent divides the dorsal-ventral axis into new cells. convergent extension occurs. early blastomeres can form a complete embryo if isolated. extraembryonic cells interact with the zygote nucleus. cytoplasmic determinants are distributed unevenly in unfertilized eggs. Correct Chapter 48 Question 6 Part A Which of the following is a direct result of depolarizing the presynaptic membrane of an axon terminal? ANSWER: Ligand-gated channels open, allowing neurotransmitters to enter the synaptic cleft. Synaptic vesicles fuse with the membrane. The postsynaptic cell produces an action potential. An EPSP or IPSP is generated in the postsynaptic cell. Voltage-gated calcium channels in the membrane open. Correct Sex Hormones and Mammalian Reproduction Sex hormones in humans regulate reproduction by promoting gametogenesis, the development of primary sex characteristics during embryogenesis, and the development of secondary sex characteristics at puberty. Part A - Hormones and secondary sex characteristics Sex hormones, including androgens, estrogens, and progesterone, are produced by the gonads in males and females and control the development of primary sex characteristics—the structures directly involved in reproduction. The sex hormones also trigger the development of secondary sex characteristics—the physical and behavioral characteristics that appear during puberty that are not directly related to reproduction. Because the principal sex hormones differ in males and females, different secondary sex characteristics develop. Sort the following secondary sex characteristics and hormones based on whether they are related to androgens, estrogens and progesterone, or neither. Drag each phrase to the appropriate bin. Hint 1. Classes of sex hormones Male sex hormones are called androgens. Testosterone is the principal androgen. Female sex hormones include progesterone and estrogens, especially estradiol. Hint 2. Can you identify male secondary sex characteristics? Identify the male secondary sex characteristics. Select all that apply. ANSWER: https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 221 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM development of facial hair breast development deepening of voice increased muscle mass increased aggressiveness fat deposition in hips increased water retention sperm production changes in calcium metabolism ANSWER: Correct Androgens, chiefly testosterone, trigger the development of male secondary sex characteristics at puberty. Estrogens, especially estradiol, and progesterone initiate the development of female secondary sex characteristics. This table lists some of the secondary sex characteristics in males and females. Secondary Sex Characteristics deep voice, male hair growth pattern, Males increased muscle size, increased aggressiveness enlarged breasts, fat deposition in hips and breasts, water retention, changes in Females calcium metabolism and bone deposition Part B - Hormonal control of the ovarian cycle in humans Hormones control the two closely linked reproductive cycles in human females—the uterine (or menstrual) cycle and the ovarian cycle. https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 222 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM During one uterine cycle, which is approximately 28 days long, the lining of the uterus undergoes hormonally-regulated changes, if no pregnancy has occurred. At the same time, the hormones also cause a series of changes to take place in an ovary, known as the ovarian cycle. The flowchart below describes the events of the ovarian cycle. Drag the names of the hormones to their appropriate locations on the flowchart, starting with the release of a hormone from the hypothalamus. Labels may be used once, more than once, or not at all. (Note: GnRH = gonadotropin-releasing hormone; LH = luteinizing hormone; FSH = follicle- stimulating hormone.) Hint 1. Changes in the ovary during the reproductive cycle This diagram illustrates the changes that take place in an ovary over the course of one reproductive cycle. An ovary contains primary oocytes in follicles, small cavities lined with protective cells. Each month, one follicle matures during the first part of the ovarian cycle. As it matures, the primary oocyte develops into the secondary oocyte, which is released at ovulation when the follicle breaks open. The ruptured follicle develops into a structure called the corpus luteum, which degenerates if the oocyte is not fertilized. Hint 2. Which endocrine glands secrete the hormones involved in the ovarian cycle? Match each hormone with the endocrine gland that secretes it. (Note: GnRH = gonadotropin-releasing hormone; LH = luteinizing hormone; FSH = follicle-stimulating hormone.) Drag each hormone to the appropriate bin. ANSWER: https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 223 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM Hint 3. What are some functions of the hormones involved in the ovarian cycle? Match each hormone with the appropriate function. (Note: GnRH = gonadotropin-releasing hormone; LH = luteinizing hormone; FSH = follicle- stimulating hormone.) Drag the terms on the left to the appropriate blanks on the right to complete the sentences. ANSWER: ANSWER: https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 224 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM Correct As shown in the diagram below, the ovarian cycle is regulated by hormones secreted by the hypothalamus (top panel) and the anterior pituitary (panel 2), as well as by the maturing follicle and corpus luteum in the ovary (panels 3 and 4). At the same time, the hormones also cause the endometrium (the lining of the uterus) to thicken and then shed (bottom panel). Part C - Preventing pregnancy Some methods of contraception, such as birth control pills and patches, use synthetic hormones to manipulate the ovarian cycle in females. Some hormone-based contraceptives contain a combination of a synthetic estradiol and a synthetic progestin (progesterone-like hormone). Other hormone-based contraceptives contain progestin only. Which statements correctly explain how the hormone-based contraceptives affect the female reproductive cycle? Select all that apply. Hint 1. Hormone levels and the ovarian and uterine (menstrual) cycles https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 225 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM The first half of the female reproductive cycle is characterized by low levels of FSH and LH. For the first few days, ovarian hormone levels are also low, and the endometrium (uterine lining) is shed (menstruation). Then, as estradiol levels rise, the endometrium begins to thicken. Ovulation occurs after estradiol levels peak and trigger a surge in FSH and LH. After ovulation, the endometrium continues to thicken in response to the ovarian hormones. If the egg is not fertilized, ovarian hormone levels drop, the uterine lining disintegrates and menstruation occurs, signaling the beginning of the next reproductive cycle. If the egg is fertilized and implants in the endometrium, the corpus luteum in the ovary continues to secrete progesterone and estradiol that maintain the endometrium. Hint 2. What are the functions of the hormones involved in the female reproductive cycle? Match each hormone with the appropriate function. Drag the terms on the left to the appropriate blanks on the right to complete the sentences. ANSWER: https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 226 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM Hint 3. How do hormones affect ovulation? Determine how each of the following hormones or hormone concentrations affects ovulation, if at all. Drag each hormone to the appropriate bin. If a hormone does not affect ovulation, drag it to the "no effect on ovulation" bin. ANSWER: ANSWER: https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 227 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM The progestin in the progestin-only pill causes changes in the endometrium that prevent implantation. The low dose of estradiol in the combination pill prevents the surge in LH production. The high dose of estradiol in the combination pill prevents ovulation. The low doses of progestin and estradiol in the combination pill have a negative feedback effect on the hypothalamus, blocking ovulation. The progestin in the progestin-only pill has a stimulatory effect on pituitary hormones. The progestin in the progestin-only pill triggers ovulation. Correct Many contraceptives rely on the delivery of synthetic hormones to block ovulation or implantation. Fertilization cannot occur without ovulation, and a pregnancy will not begin without implantation of a fertilized egg into the endometrium. Hormonal contraceptives that contain a combination of estrogen and progesterone exert a negative feedback effect on the hypothalamus and pituitary gland, inhibiting the secretion of LH and preventing ovulation. Hormonal contraceptives that contain only progestin can prevent ovulation, cause thickening of the cervical mucus so that it blocks sperm from entering the uterus, and make the uterine lining unsuitable for the implantation of a fertilized egg. Chapter 43 Question 6 Part A Vaccination increases the number of ANSWER: lymphocytes with receptors that can bind to the pathogen. epitopes that the immune system can recognize. macrophages specific for a pathogen. different receptors that recognize a pathogen. MHC molecules that can present an antigen. Correct Activity: Connective Tissue Click here to complete this activity. Then answer the questions. Part A How does connective tissue differ from the other three major tissue types? https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 228 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM ANSWER: Connective tissue often consists of relatively few cells embedded in an extracellular matrix. Connective tissue consists of contractile proteins. Connective tissue consists of cells capable of transmitting electrical impulses. There are three types of connective tissue. Connective tissue is found lining body surfaces. Correct This describes many connective tissues, such as loose connective tissue. Part B Which of these describes loose connective tissue? ANSWER: It is a loose weave of fibers that functions as a packing material. It is composed of many fibers that connect bone to bone and muscle to bone. It is a rigid material that provides structural support. It transports nutrients and gases from one part of the body to another. It plays a role in padding, insulation, and energy storage. Correct Loose connective tissue is a packing material that serves, for example, to hold organs in place. Part C Cartilage is found _____. ANSWER: surrounding organs such as the kidneys in the heart at the ends of bones such as the femur covering the surface of your body connecting one bone to another Correct The ends of long bones, such as the femur, have a cartilage cap. Part D _____ is the connective tissue specialized for transport. ANSWER: https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 229 of 300 HW 02: Animal Form & Function 5/13/15 4:53 PM Bone Blood Adipose tissue Muscle tissue Cartilage Correct Blood is specialized for the transport of substances such as nutrients, wastes, and gases. Chapter 50 Question 2 Part A The middle ear converts ANSWER: air pressure waves to fluid pressure waves. pressure waves to hair cell movements. fluid pressure waves to air pressure waves. air pressure waves to nerve impulses. fluid pressure waves to nerve impulses. Correct Chapter 40 Question 1 Part A The body tissue that consists largely of material located outside of cells is ANSWER: epithelial tissue. smooth muscle. skeletal muscle. nervous tissue. connective tissue. Correct Activity: Control of Water Reabsorption https://session.masteringbiology.com/myct/assignmentPrintView?displayMode=studentView&assignmentID=3451230 Page 230 of 300
Related Downloads


Explore
Post homework questions online and get free homework help from tutors.
Learn More
Improve Grades
Help Others
Save Time
Accessible 24/7
  269 People Browsing
Poll
Do you trust social media networks with protecting your privacy?
No
Not sure
Yes
If you would like to vote in this poll, please login or register